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HomeMy WebLinkAboutagenda.council.worksession.20240805AGENDA CITY COUNCIL WORK SESSION August 5, 2024 4:00 PM, City Council Chambers 427 Rio Grande Place, Aspen I.Work Session I.A Board and Commission Interviews I.B Castle Creek Bridge Feasibility Follow Up (Part 1) Zoom Meeting Instructions Join from a PC, Mac, iPad, iPhone or Android device: Please click this URL to join: https://us06web.zoom.us/j/83295725560? pwd=N1bnFLqcN1yxqg2cp4F12JVU8VUSJl.1 Passcode: 81611 Or join by phone: Dial: US: +1 346 248 7799 Webinar ID: 832 9572 5560 Passcode: 81611 International numbers available: https://us06web.zoom.us/u/kcPeKSPjp5 Board & Commission Interviews MEMO - 8.5.24.pdf 2024_8-5_Castle_Creek_Bridge_Work_Session_Memo_SGO.docx Attachment A - Letter From CDOT dated July 10 2024.pdf Attachment B - Alternatives Footprint Analysis and Sensitivity Analysis Memo.pdf Attachment C - Funding and Financial Assessment Memo.pdf Attachment D - Traffic Modeling Memo.pdf Attachment E - S-Curve Technical Memo.pdf Attachment F - Analysis of Sidewalk Removal Memo.pdf Attachment G - Economic Impact Analysis Memo.pdf 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 MEMORANDUM TO:Mayor and Council FROM:Jenn Ooton, Senior Project Manager Pete Rice, PE, Director of Transportation and Parking Lynn Rumbaugh, Mobility Division Manager Carly McGowan, PE, Senior Project Manager THROUGH:Sara Ott, City Manager Tyler Christoff, PE, Public Works Director DATE OF MEMO:July 29, 2024 MEETING DATE:August 5, 2024 RE:Castle Creek Bridge Evaluation REQUEST OF COUNCIL: The work session will focus on the results of the second phase of the Jacobs Engineering Castle Creek Bridge evaluation as directed by Council during the April 15 work session. SUMMARY AND BACKGROUND: In the 1990s, Aspen was facing heavy traffic, congestion issues, and deteriorating air quality. In response, the Colorado Department of Transportation (CDOT), the Federal Highway Administration (FHWA), and the City of Aspen worked together to develop the Record of Decision that would drive the implementation of transportation improvements along the Highway 82 corridor between Brush Creek and Aspen. The Record of Decision, also known as the “ROD”, was the outcome of a multi-year process driven by the National Environmental Policy Act, or “NEPA”. The Record of Decision is a legal document between CDOT and FHWA that governs transportation infrastructure improvements and identifies mitigation for environmental impacts. It is still valid today. The set of improvements outlined in the ROD and vetted through the NEPA process are referred to as the Preferred Alternative (“PA”). Over the past 25 years, CDOT, the city and other regional partners have increased transit connectivity, implemented transportation management measures including paid parking, constructed the Maroon Creek Bridge and the roundabout, and realigned Owl Creek Road. The major remaining piece of the ROD that has not been implemented is the construction of a new Castle Creek Bridge. 15 The existing Castle Creek Bridge was built in 1961 with a design life of 50 years. That means that the bridge is more than 10 years past its design life. Increased maintenance is required on the aging bridge to keep it in a safe and usable condition. During the NEPA process, 43 alternatives for the alignment of a new Castle Creek Bridge were screened. The highway component of the Preferred Alternative consists of a two-lane parkway that generally follows the existing alignment, except east of the roundabout where the alignment departs from existing and turns south across the Marolt-Thomas Property. The alignment would utilize a new bridge to the south of the existing alignment and then would tie into W. Main St at the intersection with 7 th Street. The transit component of the PA includes a light rail transit (LRT) system, that if local support and/or funding are not available could be developed initially as exclusive bus lanes. DISCUSSION: In April of 2024, Jacobs Engineering presented results of the following studies to City Council: -Feasibility Study for Rehabilitation or Replacement of Bridge in Place -Feasibility Study for S-Curves Softening -NEPA Options and Implications Following the presentation from Jacobs Engineering on April 15, Council requested additional information on items listed as follows: -Alternatives Footprint Analysis and Sensitivity Analysis in Attachment B -Funding and Financial Assessment, included in Attachment C -Traffic Model Development for Alternatives and Construction Phasing, included in Attachment D -S-Curve Refinement – 15% Conceptual Plans and Cost Estimate, included in Attachment E -Analysis of Removal of Pedestrian Route on CCB, included in Attachment F -Economic Impact Analysis, included in Attachment G. Additionally, staff will review a response from CDOT and FHWA dated July 10, 2024 regarding questions asked by City Council. The letter is included as Attachment A. FINANCIAL IMPACTS: Staff will submit cost impacts after receiving Council direction. The City of Aspen will be responsible for funding modifications to the existing Record of Decision or pursuing a new NEPA process. 16 The project fund has a lifetime budget of 8.5 million dollars. The 2024 appropriation has a remaining budget of $774,940.75. ENVIRONMENTAL IMPACTS: For any construction of the Entrance to Aspen project, the project must follow National Environmental Protection Act (NEPA) requirements. The environmental impacts of the Preferred Alternative were heavily examined during the EIS process in the 1990s. Should the Council choose to deviate from the Preferred Alternative with an alternative solution, the environmental impacts will be required to be studied during a new or supplemental EIS process. The City of Aspen must follow this federal process that involves the greater community’s input in a similar fashion to the 1998 Record of Decision and cannot be fully decided by Aspen City Council alone. According to the July 10, 2024 letter from CDOT, the NEPA requirements will be applicable to this project whether the City pursues a self-funding option or state/federal funding. ALTERNATIVES: The purpose of this work session is to discuss alternatives for the Castle Creek Bridge with Council to determine next steps. RECOMMENDATION: The August work sessions will review the additional analysis by Jacobs. This is set only for a discussion at the Council table. CITY MANAGER COMMENTS: I have directed staff and the consultant to present information in the order listed below. I encourage the Council to hear presentation and ask clarifying questions before entering into debate or staff direction. PART ONE Introduction – Sara Ott Presentation Overview – Jacobs Land swap history – staff/Jacobs CDOT/FHWA coordination and responses – Jacobs Alternative footprints and sensitivity analysis - Jacobs Traffic Modeling - Jacobs PART TWO 3-lane bridge detail – Jacobs S-curve refinement – Jacobs Economic Analysis – Jacobs 17 Funding Opportunities and Considerations – Jacobs Full Council debate/discussion Any staff direction from Council The Council may break, adjourn for the evening, or continue as it sees fit. A light dinner will be served for the Council, available at 7 pm. Attachments: Attachment A – Letter from CDOT dated July 10, 2024 Attachment B – Alternatives Footprint Analysis and Sensitivity Analysis Memo Attachment C – Funding and Financial Assessment Memo Attachment D – Traffic Modeling Memo Attachment E – S-Curve Technical Memo Attachment F – Analysis of Sidewalk Removal Memo Attachment G – Economic Impact Analysis Memo 18 19 20 21 22 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 1 Memorandums Subject: Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives Project Name: New Castle Creek Bridge Investigative Study with Revised Scope (the Project) Attention: City of Aspen (the City) From: Jacobs Date: July 31, 2024 Copies to: Project File 1. Introduction This memorandum (memo) summarizes a high-level footprint and National Environmental Policy Act (NEPA) assessment performed by Jacobs for three alternatives focused on the segment of State Highway (SH) 82 between Maroon Creek Road and 7th Street. These alternatives, which are described in Section 2, are refined versions of alternatives previously considered in the Entrance to Aspen Environmental Impact Statement (EIS) process. These alternatives include the following:  Phased Preferred Alternative (PA): Phased PA version of the from the 1998 Record of Decision (ROD) (FHWA 1998).  Couplet (one-way pair): Considered in the Draft Environmental Impact Statement (DEIS) but eliminated during the comparative screening. An alternative version of the couplet was evaluated in the Supplemental DEIS but used a different alignment through the open space and included a roundabout at Cemetery Lane. The couplet (one-way pair) has been studied further since the EIS/ROD and has been referred to more recently as the Splitshot.  Three-lane Shifted Bridge: Three-lane options were considered in the DEIS but eliminated in the fatal flaw screening. Another version of the three-lane option was developed more recently to address the aging Castle Creek Bridge and improve operations along SH 82 while avoiding a reroute of SH 82 through the Marolt-Thomas property to the intersection of 7th Street and Main Street. The assessment presented in this memo is intended to provide an indication of how the alternatives may fair in a supplemental NEPA evaluation. Understanding potential outcomes of a NEPA alternatives process informs decision making to identify an efficient path forward given the regulatory context for improvements to this segment of SH 82. 23 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 2 2. Alternatives The alternatives evaluated in the EIS (CDOT 1997) included a combination of highway and intersection improvements, a transit system, and an incremental transportation management program. The alternatives in this memo focus on highway, intersection, and transit improvements. 2.1 Phased Preferred Alternative The Phased PA follows the modified-direct alignment east of the Maroon Creek Road roundabout. The SH 82 alignment would shift southeast across the Marolt-Thomas property and through a cut-and-cover tunnel 400 feet long and connect with the intersection of 7th Street and Main Street via a new Castle Creek Bridge. The initial phase of the PA in this segment includes widening SH 82 to include one travel lane and one bus-only lane in each direction. The new bus-only lanes would connect with the existing bus-only lanes that exist on SH 82 west of Maroon Creek Road. Refinements to the Phased PA design include smoothing curves through the Marolt-Thomas property, routing the Marolt Trail over the cut-and-cover tunnel, shortening the span of the Castle Creek Bridge, and providing a signalized intersection with a left turn lane on 7th Street. The roadway width constructed for this initial phase would not accommodate future light rail that could ultimately replace the bus-only lanes in the corridor. The abandoned segment of SH 82 west of Cemetery Lane would be removed and restored as open space; however, it could also be used for a future evacuation event. This would provide the town with a redundant route. The remainder of the old SH 82 alignment between Cemetery Lane and 7th Street would be converted to a local street. Figure 1 shows a plan view of the Phased PA with minor design refinements. Figures 2 and 3 shows the cross sections of the Phased PA along the modified-direct alignment from the Supplemental DEIS. The cross section for the tunnel is slightly wider than the other segments to provide adequate space for future light rail transit (LRT). This alignment still assumes the ROD condition that the Berger Cabin at 835 West Main Street would be relocated on the parcel and land acquisition is needed for a good portion of the parcel (see Figure 2, roadway cross section). This alignment impacts parking on both sides of West Main Street (west of 7th Street), however, right-of-way would not be required on the north side of West Main Street. Additional parking could be provided on both sides of North 7th Street, as the same number of lanes on North 7th Street is no longer needed for this version. Figure 4 was developed to visualize how the alignment looks when it touches down between Castle Creek and North 7th Street. 24 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 3 Figure 1. Phased Preferred Alternative – Plan View GP =general purpose BRT = bus rapid transit Figure 2. Phased PA – Phased PA – Roadway Cross Section ROW = right-of-way 25 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 4 Figure 3. Phased Preferred Alternative – Cut-and-cover Tunnel Cross Section Figure 4. Phased Preferred Alternative – Visualization of Touchdown before 7th and Main Street 2.2 Splitshot The Splitshot (referred to as the couplet [one-way pair] in the DEIS) uses a combination of the existing alignment and the modified-direct alignment east of the Maroon Creek Road roundabout. Just east of the roundabout, SH 82 would split into two separate alignments, each with one direction of traffic. Traffic would flow westbound (out of town 26 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 5 or out-bound) on the existing SH 82 alignment and eastbound (into town or in-bound) on the modified-direct alignment through the Marolt-Thomas property. Each alignment would have one travel lane and one bus-only lane. The new bus-only lanes would connect with the existing bus-only lanes that exist on SH 82 west of Maroon Creek Road. The roadway width constructed for this initial phase would not accommodate the future light rail that could ultimately replace the bus-only lanes in the corridor. Figure 5 shows a plan view of the Splitshot with minor design refinements. Figures 6 and 7 show the cross section of Splitshot along the modified-direct alignment. The cross section for the tunnel is slightly wider than the other segments to provide adequate space for future LRT. There are two key differences between the Splitshot evaluated in this memo and the couplet alignment (one-way pair) evaluated in the DEIS. The first is that the alternative in the DEIS did not include the roundabout at Maroon Creek Road that exists today. Without this roundabout, operational problems were identified for this alternative because eastbound SH 82 traffic from Cemetery Lane would have to turn onto westbound SH 82 and make a U-turn at Maroon Creek Road where eastbound and westbound traffic come together. The couplet (one-way pair) was screened out during the comparative screening because of the U-turn issue and was not evaluated in detail in the DEIS. The roundabout at Maroon Creek Road minimizes these operational issues. The other difference is that the Splitshot design evaluated in this memo uses the cut-and-cover tunnel through the Marolt-Thomas property to minimize open space impacts. Because the couplet alignment (one-way pair) in the DEIS was screened out before detailed evaluation, it was never evaluated with profile options (at-grade or cut-and-cover). Other minor refinements to the Splitshot design include smoothing curves with a slightly more direct route through the Marolt-Thomas property than is used for the Phased PA, routing the Marolt Trail over the tunnel, shortening the span of the new Castle Creek Bridge, providing a sidewalk across the new Castle Creek Bridge, and providing a signalized intersection with left turn lane on 7th Street. To improve operations for westbound traffic along the existing SH 82 alignment, there is curve softening on the northeast corners of North 7th Street and Main Street. This alignment still assumes the ROD condition that the Berger Cabin at 835 West Main Street would be relocated on the parcel and land acquisition is needed for a good portion of the parcel (refer to Figure 6, roadway cross section). This alignment impacts parking along the south side of Main Street (west of 7th Street). On the north side, the footprint is minimized to maintain local access to North 8th Street and reconfigures parking. Additional parking could be provided on the west side of North 7th Street because the same number of lanes on North 7th Street is no longer needed for this version. Figure 8 was developed to visualize how the alignment looks when it touches down between Castle Creek and North 7th Street. 27 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 6 Figure 5. Splitshot – Plan View Figure 6. Splitshot – Roadway Cross Section Figure 7. Splitshot – Cut-and-cover Tunnel Cross Section 28 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 7 Figure 8. Splitshot – Visualization of Touchdown before 7th and Main Street 2.3 Three-lane Shifted Bridge The Three-lane Shifted bridge uses the existing SH 82 alignment east of the Maroon Creek Road roundabout. The existing Castle Creek Bridge would be replaced with a wider bridge to facilitate continued two-lane traffic on the bridge during construction. The new bridge would include one general purpose travel lane in each direction, a bus-only lane in the westbound (out of town) direction, and a sidewalk. The new bus-only lane would connect with the existing westbound bus-only lane and a relocated bus stop along SH 82 west of Maroon Creek Road via a westbound bus bypass lane added west of Cemetery Lane. The bridge width would not accommodate a future eastbound (inbound) bus lane on the existing SH 82 alignment. However, in the future, the bridge could be reconfigured to accommodate one general purpose lane in each direction and a single-track light rail service line. This alternative also includes softening the S-curves along SH 82 to improve traffic flow and safety. The S-curves will feature a general purpose and dedicated bus lane in each direction of SH 82 essentially from 8th Street to 5th Street. Figure 9 shows a plan view of the Three-lane Shifted Bridge with bus bypass lane. The bus bypass lane requires extending the existing pedestrian underpass, and the current bus stop is relocated to the west. Additionally, the trail along the City’s golf course is relocated through this stretch. Figures 10 and 11 show select cross sections of this option. 29 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 8 Figure 9. Three-lane Shifted Bridge – Plan View Figure 10. Three-lane Shifted Bridge – Bus Bypass Lane Cross Section 30 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 9 Figure 11. Three-lane Shifted Bridge – Castle Creek Bridge Cross Section 2.4 Footprint Analysis Jacobs developed conceptual designs for all three alternatives to establish footprints for the sensitivity analysis (refer to Attachment 1 for details). For the PA and Splitshot alternatives, this approach involved replicating most of the alternative descriptions in the EIS, making modifications, assumptions, and accommodations as needed. The platform widths for these two alternatives do not include the LRT envelope across the Marolt-Thomas open space, except in the cut-and-cover tunnel. Estimating property impacts required developing land survey data. An existing ground surface was generated from light detection and ranging (LiDAR) data and supplemented with field survey in the area from the Castle Creek to the 7th Street and West Main Street intersection. Roadway cross-section elements were generated at specific intervals to determine cut and fill limits for each alternative. Jacobs also prepared conceptual bridge design for the Phased PA and Splitshot alternatives to identify the basic footprints of the bridge and potential construction impacts (details in Attachment 1). This information has been prepared for the Three- lane Shifted alternative as part of the SH 82 Over Castle Creek Bridge Feasibility Study (Jacobs 2024a). 3. High-level NEPA Assessment In a July 10, 2024, letter (CDOT, pers. comm. 2024), the Colorado Department of Transportation (CDOT), in coordination with the Federal Highway Administration (FHWA) and the state attorney general’s office, responded to several EIS and bridge replacement questions from the City. In this letter, CDOT indicated that regardless of how the remainder of the corridor improvements are funded, the PA will remain in effect unless CDOT and FHWA choose to withdraw the ROD, and that a new Supplemental Environmental Impact Statement (SEIS) (at a minimum) would be required to change the decision made in the ROD. Given this information, this high-level NEPA assessment 31 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 10 uses screening criteria consistent with the purpose, needs, and objectives developed during the Entrance to Aspen EIS process. The intent is to provide some indication of how these three alternatives might compare to each other in a SEIS or new NEPA process. This assessment is intended only to guide decision making and not intended to supplant NEPA analyses. Outcomes for NEPA processes cannot be predetermined. This assessment factors in updated conditions and information including the following:  Although the PA in the Final EIS and ROD assumed there would be a roundabout at Maroon Creek Road, the alternatives in the DEIS did not. This includes the Splitshot (couplet) that was eliminated during the comparative screening in the DEIS.  Design refinements for the S-curves are included in the Splitshot and Three-lane Shifted bridge alternatives to improve traffic flow and safety on SH 82. The Phased PA alternative does not include these improvements, as SH 82 would no longer use the existing alignment under that option.  Traffic modeling of the alternatives has been completed using future 2050 traffic volumes, providing information on transportation and transit metrics.  Historic survey work completed this summer provides updated information on historic resources.  Transportation corridor ROW across the Marolt-Thomas open space has been conveyed to CDOT (executed in 2002 for 4.47 acres [City 2002]). Criteria used in this assessment are identified in Table 1. Clean Air Act requirements and community acceptability were not considered for the purposes of this exercise. Because the project area is no longer a nonattainment area, conformity would not be required to meet Clean Air Act requirements. The state has new rules related to greenhouse gas (GHG) emissions, but GHG modeling is beyond the scope of this exercise. Determining community acceptability would require outreach efforts that also are beyond the scope of this exercise. However, the criteria used give a reasonable indication of how these alternatives may fare in a SEIS or new NEPA process. Table 1 summarizes the results followed by a discussion of how each alternative performed. A rating of good, fair, or poor is assessed for each alternative. 32 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 11 Table 1. Screening Summary Criteria Phased PA Splitshot Three-lane Shifted Operations Provides capacity for forecasted person trips (year 2050) Good Provides capacity for eastbound and westbound travel forecasts. Bus operations in dedicated bus lanes can be increased to meet demand. Fair Improves overall capacity, but travel times in the morning peak period are substantially impacted by Cemetery Lane traffic using the Maroon Creek Road roundabout to go east on SH 82. Bus operations in dedicated bus lanes can be increased to as demand increases, but operations at the Maroon Creek Road roundabout would continue to negatively affect ability to serve forecasted trips during the morning peak period. Fair Performs better than the Splitshot for morning peak period but offers no improvement over the No Build scenario for eastbound travel. Offering only a westbound bus lane limits ability to serve more person trips as demand increases. Limits vehicle trips into Aspen Good No new capacity for passenger vehicles. Limits vehicle trips by encouraging transit use into Aspen. Fair No new capacity for passenger vehicles. Ability to limit vehicle trips into Aspen is impacted by slow transit travel times in morning peak period caused by substantial operational issues at Maroon Creek Road roundabout. Poor No new capacity for passenger vehicles. Offers no incentive for eastbound mode-shift for travelers coming into Aspen. 33 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 12 Criteria Phased PA Splitshot Three-lane Shifted Provides more accessible transportation that increases the mobility of the community Good Eastbound and westbound bus -only lanes enhance transit service, improving the mobility of the community. Fair Eastbound and westbound bus-only lanes enhance transit service, improving the mobility of the community. However, no improvements for morning peak- period travel. Fair Westbound bus-only lane with bypass enhances transit service. Improves mobility for westbound travel only. Allows for future transit options and upgrades Good Could accommodate future LRT platform with minor widening. Existing easement across Marolt-Thomas accommodates future LRT. Good Could accommodate future LRT platform with minor widening. Existing easement across Marolt-Thomas accommodates future eastbound LRT. Fair Three-lane bridge and S-curve widening is designed to accommodate a single-track LRT and two general purpose lanes in the future. Safety Provides system redundancy for emergency access Good Provides a secondary route for emergency access. Good Provides a secondary route for emergency access. Poor Provides no system redundancy for emergency access. Addresses known safety issues on SH 82 and S-curves Good Eastbound and westbound SH 82 travelers avoid S-curves, and both directions of traffic are separated by raised median. Good Eastbound SH 82 travelers avoid S-curves. Softens S-curves to facilitate westbound travelers. One-way couplet separates opposing directions of traffic. Fair Softens S-curves to facilitate both directions of travel. Provides wider lanes in curves. No separation for opposing directions of traffic. 34 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 13 Criteria Phased PA Splitshot Three-lane Shifted Provides safe access at all intersections for all movements Good New signalized intersection at Main and 7th Street improves safety by providing controlled access for all movements. Cemetery lane intersection converted into two-way curve eliminating intersection conflict points. Good New signalized intersection at Main and 7th Street maintains safety by restricting some movements. Cemetery Lane traffic routed through Maroon Creek Road roundabout. Fair Some intersection access restricted to reduce conflicts in S-curves. Cemetery Lane signal remains. Provides safety improvements for cyclists and pedestrians Fair Reduces risk of vehicle and pedestrian conflicts on existing alignment by preserving existing sidewalks on existing Castle Creek Bridge and removing SH 82 traffic from this route. No pedestrian crossing over new Castle Creek Bridge because of platform width restriction. Good Preserves existing sidewalks on existing Castle Creek Bridge. Adds an additional 10-foot pedestrian crossing across new Castle Creek Bridge. Fair Provides 10-foot pedestrian crossing across Castle Creek along north side (existing location). Community and Environmental Impacts Minimizes/ mitigates property/ROW impacts Good ~0.8 acre of ROW needed (existing transportation easement through Marolt-Thomas minimizes additional ROW needs). Good ~0.8 acre of ROW needed (existing transportation easement through Marolt-Thomas minimizes additional ROW needs). ROW also could be needed along existing alignment for westbound LRT. Fair ~1.7 acres of ROW needed (impacts along the City golf course; potential risk for full property acquisition under shifted bridge). 35 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 14 Criteria Phased PA Splitshot Three-lane Shifted Minimizes/ mitigates historic resource impacts Fair No adverse impacts with mitigation; assume Berger Cabin is relocated. Fair No adverse impacts with mitigation; assume Berger Cabin is relocated. Good No adverse impacts. Minimizes/ mitigates recreation impacts Fair SH 82 rerouted through Marolt-Thomas open space; tunnel minimizes impacts. Reroute Marolt Trail over cut-and-cover tunnel. Loss of open space was already mitigated in 2002 land swap. Fair Inbound direction of SH 82 rerouted through Marolt-Thomas open space. Tunnel minimizes impacts. Reroute Marolt Trail over cut-and-cover tunnel. Loss of open space was already mitigated in 2002 land swap. Fair Minor encroachment into Bugsy Barnard Park; encroaches into the golf course requiring reconfiguration of one hole; realign Golf Course Trail. 36 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 15 3.1 Phased Preferred Alternative Assessment 3.1.1 Operations The Phased PA provides dedicated bus lanes in each direction to provide reliable transit service with improved transit peak-period travel times as compared with the No Build scenario (Jacobs 2024b). This alternative performs the best of the alternatives evaluated and the improved service would likely increase demand for transit. By providing improved transit service, the Phased PA is expected to limit passenger vehicle trips into Aspen by encouraging transit use over passenger vehicle trips. The Phased PA provides no additional capacity for passenger vehicle trips. Improved transit service under the Phased PA increases the mobility of the community both for eastbound and westbound trips. The refined version of the Phased PA evaluated in this memo narrows the cross section as compared with the version in the ROD to minimize impacts and, therefore, does not provide a transit envelop for future light rail. However, only minor widening would be needed to accommodate future light rail, and the existing transportation easement through the Marolt-Thomas property would accommodate this future transit improvement. 3.1.2 Safety The Phased PA provides a new bridge across Castle Creek while preserving the existing Castle Creek Bridge. The existing alignment, which would connect to Cemetery Lane, would serve as an alternative route in case of a substantial emergency or congestion along the new SH 82 alignment. This alternative would address existing SH 82 safety issues by diverting SH 82 traffic from the S-curves, eliminating the need for SH 82 vehicles to navigate these sharp curves. Additionally, both directions of traffic would be separated by a 10-foot raised median (Figure 2) which eliminates potential head-to- head traffic conflicts that exist today. A new signalized intersection would be implemented at 7th Street and Main Street, providing controlled access movements to further improve safe operations. The new Castle Creek Bridge crossing would not include sidewalks; however, the existing bridge would continue to serve pedestrians and would not carry the SH 82 traffic, reducing potential for traffic and pedestrian conflicts. 3.1.3 Community and Environmental Impacts Because CDOT and the City already executed a permanent easement through the Marolt-Thomas property, much of the ROW needed for the Phased PA already exists. However, an additional 0.8 acre would be needed on the private Berger property, east of Castle Creek, because the alignment traverses this property to connect with West Main Street. 37 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 16 Although an easement exists through the Marolt-Thomas property, the property is currently used for recreation. Implementing the Phased PA would introduce a transportation route through the open space, disrupting existing recreation activities. The cut-and-cover tunnel is intended to minimize the amount of disruption. The Marolt Trail would be routed over the cut-and-cover tunnel with no impact to long-term recreation use of this facility. Additionally, as part of the 2002 land swap to mitigate open space impacts, CDOT already provided far more land to the City and Pitkin County for open space than would be impacted once the PA is fully implemented. The historic survey conducted this summer confirmed previous historic determinations from the EIS and 1987 Reevaluation (CDOT and FHWA) and recommended an additional property—the condominiums at 937 to 947 West Hallam Street—as potentially eligible to the National Register of Historic Places. The PA would not affect this property. 3.2 Splitshot Assessment 3.2.1 Operations Similar to the Phased PA, the Splitshot provides dedicated bus lanes in each direction. This alternative provides improved transit service with improved evening peak-period transit travel times as compared with the No Build scenario (Jacobs 2024b). This improved service is expected to increase demand for transit. However, morning peak- period travel times are substantially impacted by operational issues caused by traffic from Cemetery Lane using the Maroon Creek Road roundabout to turn around and head east into Aspen. If the morning transit travel times discourage transit use for commuters heading into Aspen in the morning, these same commuters would be using a vehicle to return home in the evening. Because travel times are directly related to ridership, the level of transit ridership would not likely be as high as the Phased PA. The lower transit ridership also likely equates to the Splitshot not performing quite as well as the Phased PA in limiting passenger vehicle trips into Aspen. The dedicated bus lanes would still improve accessibility and mobility for the community. Use of a bus bypass lane at the Maroon Creek Road roundabout, as is used in the Three-lane Shifted bridge, would alleviate the transit issues but would substantially increase recreation impacts similar to the Three-lane Shifted bridge impacts. Similar to the Phased PA, the Splitshot uses a cross section that does not provide a transit envelop for future light rail. This design decision was intended to reduce impacts. However, only minor widening would be needed to accommodate future light rail for eastbound travelers, and the existing transportation easement through the Marolt-Thomas property would accommodate this future transit improvement. Additional widening would also be needed for westbound transit users along the existing alignment, which would require additional ROW. 38 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 17 Regarding historic effects, the Splitshot is not expected to impact the condominiums at 937 to 947 West Hallam Street. 3.2.2 Safety Similar to the Phased PA, the Splitshot provides two routes across Castle Creek, providing system redundancy in case of a substantial emergency or congestion along SH 82 between Maroon Creek Road and Main Street. The one-way couplet eliminates the potential for head-to-head traffic conflicts that exist today. This alternative would further address SH 82 safety issues by diverting eastbound SH 82 traffic from the S-curves, greatly reducing the number of vehicles traveling through these sharp curves. The S-curves would be softened and widened to safely facilitate westbound travel. A new signalized intersection with westbound channelization would be planned for Main Street and 7th Street, providing controlled access movements. The Cemetery Lane signal would be eliminated to facilitate westbound travel. This alternative provides a 10-foot-wide sidewalk on the new Castle Creek Bridge, which adds redundancy and improves connectivity for bicyclists and pedestrians. The existing 8-foot and 5-foot sidewalks on the existing Castle Creek Bridge would remain. 3.2.3 Community and Environmental Impacts Because CDOT and the City already executed a permanent easement through the Marolt-Thomas property, much of the ROW needed for the Splitshot already exists. No additional ROW would be needed along the existing alignment. However, an additional 0.8 acre would be needed on the private Berger property east of Castle Creek because the alignment traverses this property to connect with West Main Street. Even though this platform width is narrower than the Phased PA, the acreage is the same because the alignment severs the property into two pieces, making the north portion unusable and thereby assumed to be acquired. Although an easement exists through the Marolt-Thomas property, the property is currently used for recreation. Implementing the Splitshot would introduce a transportation route through the open space, disrupting existing recreation activities. The cut-and-cover tunnel and narrower platform width is intended to minimize the amount of disruption. The Marolt Trail would be routed over the cut-and-cover tunnel with no impact to long -term recreation use of this facility. This alternative would require some ROW from the condominiums at 937 to 947 West Hallam Street and, therefore, would impact this potentially historic property. 39 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 18 3.3 Three-lane Shifted Bridge Assessment 3.3.1 Operations Unlike the Phased PA and the Splitshot alternatives, the Three-lane Shifted bridge alternative only has a dedicated westbound bus lane rather than dedicated bus lanes in both directions. The proposed westbound bus lane would bypass the Maroon Creek Road roundabout, which would result in better westbound peak-hour transit travel times when compared to the No Build scenario or the Phased PA and Splitshot alternatives (Jacobs 2024b). However, eastbound transit travel times for this option do not offer an improvement over the No Build scenario and do not perform as well as the Phased PA. This alternative does not perform as poorly as the Splitshot during the morning peak period due to the operations issues with the Splitshot at the Maroon Creek Road roundabout. Inbound traffic (general and transit) is impaired by the additional extra Cemetery Lane traffic. With transit improvements only in the westbound direction, the Three-lane Shifted bridge alternative would not limit passenger vehicle trips into Aspen and does less to improve accessibility and mobility for the community. The Three-lane Shifted bridge alternative is not designed to accommodate bus-only lanes in both directions in the future. However, the bridge is designed to accommodate a single-track LRT in the future. This would allow LRT in both directions; however, operations would be limited by the single track across the bridge. 3.3.2 Safety The Three-lane Shifted bridge alternative does provide an additional lane across the Castle Creek crossing for emergency access or evacuations but does not provide second redundant route. This alternative does not eliminate potential head-to-head vehicle conflicts along this segment of SH 82. The S-curves would be softened and widened to improve safety for both directions of travel, with some intersection movements restricted. The existing 8 -foot and 5-foot sidewalks on the existing Castle Creek Bridge would be replaced with a new 10-foot-wide sidewalk over Castle Creek, which is wider for bicyclists and pedestrians to safely pass by one another. 3.3.3 Community and Environmental Impacts This alternative requires approximately 1.7 acres of ROW along the existing SH 82 alignment, impacting the golf course and the Bugsy Barnard Park properties. No amenities at the Bugsy Barnard Park would be impacted, but reconfiguration of one hole would be needed to accommodate widening at the golf course. The Golf Course Trail would also need to be realigned. Long-term recreation impacts are anticipated to be minimal with mitigation. 40 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 19 4. Conclusion Based on the alternative evaluation criteria used in the EIS, the Phased PA performs the best of the three alternatives. It is the only alternative that would meet person trip capacity demands in the morning and evening peak periods. The transit improvements are likely to encourage transit use, thereby limiting vehicle trips into Aspen and improving the mobility of the community. The Phased PA also has good potential for future transit options because the ROW for LRT is already purchased, and minimal widening would be needed to upgrade from bus-only lanes to LRT. The Phased PA addresses known safety issues along SH 82 and at intersections and provides system redundancy for emergency evacuations. The ROW impacts of implementing the Phased PA are minimal because most of the necessary ROW was already acquired by CDOT in 2002. Routing SH 82 through the Marolt -Thomas open space would disrupt recreation activities; however, the cut-and-cover tunnel would reduce the long-term disruption. Additionally, as part of the 2002 land swap to mitigate open space impacts, CDOT already provided far more land to the City and Pitkin County for open space than would be impacted once the PA is fully implemented (City 2002). As currently designed, the Splitshot has operational issues at the Maroon Creek Road roundabout that would substantially impact travel times in the morning peak period. This issue limits the effectiveness of implementing the bus-only lanes. This issue could be mitigated somewhat by using a bus bypass lane at the Maroon Creek Road roundabout, similar to what is used in the Three-lane Shifted bridge alternative. With this design change, the Splitshot may perform similarly to the Phased PA. However, future transit expansion for the Splitshot may be more challenging than the Phased PA because the westbound LRT is routed along the existing alignment and would need additional ROW. The Three-lane Shifted bridge alternative would not achieve some of the Entrance to Aspen Final EIS objectives because it only provides a dedicated bus lane in the westbound direction. This alternative would not meet 2050 forecasted person trips because it offers no improvement over the No Build scenario for eastbound travel into Aspen. Consequently, it would not limit vehicle trips into Aspen and does little to improve mobility for the community. Also, it would not provide a redundant route for emergency evacuation. If these three alternatives were evaluated in an Entrance to Aspen SEIS, the Phased PA would likely remain as the selected alternative without substantive changes to the evaluation criteria. 41 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 20 5. References City of Aspen (City). 2002. Quitclaim Deed. Colorado Department of Transportation (CDOT). 1997. State Highway 82 Entrance to Aspen: Final Environmental Impact Statement, Section 4(f), Volume I. Project STA 082A-008. August. Colorado Department of Transportation (CDOT). 2024. Personal communication (letter) with the City of Aspen. July 10. Colorado Department of Transportation and Federal Highway Administration (CDOT and FHWA). 1987. Reevaluation of the State Highway 82-Entrance To Aspen Final Environmental Impact Statement And Record Of Decision. Project No. CC-0821-080. June. https://www.codot.gov/projects/archived-project-sites/SH82/documents/ 1998ROD.pdf. Federal Highway Administration (FHWA). 1998. State Highway 82 Entrance to Aspen: Record of Decision. Project STA 082A-008. August. https://www.codot.gov/projects/ archived-project-sites/SH82/documents/1998ROD.pdf. Jacobs. 2024a. State Highway (SH) 82 Over Castle Creek Bridge Feasibility Study. April. Jacobs. 2024b. Castle Creek Bridge – Operational Traffic Analysis. July. 42 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 1 Attachment 1: Footprint Analysis Alternatives Methods and Approach Jacobs developed conceptual designs for all three alternatives evaluated in the sensitivity analysis to determine approximate footprints. For the Phased PA alternative, this approach involved the following:  Replicating most of the description and platform widths of the Preferred Alternative (PA) as documented in the 1998 Record of Decision (ROD) (FHWA 1998). One exception to the platform width is omitting the light rail transit (LRT) envelope across the Marolt-Thomas open space (except in the cut-and-cover tunnel).  Establishing an alignment with profile from SH 82 east of the roundabout to 7th and Main Street. - Assumes profile for cut-and-cover and bridge would need to be optimized in later engineering stages, which could result in different impacts.  Modeling the alternative in Civil3d to mimic platform widths shown in the ROD, with the exception of not including the light rail platform. Bridge platform width (73 feet) does not include a sidewalk.  Considerations that an LRT component could be provided for in the future.  Assumption that intersection at Cemetery Lane is transformed into a two-way curved roadway.  Consideration that a transportation easement exists for a future roadway.  Consideration that the Berger Cabin at 834 West Main Street is to be relocated in accordance with the ROD and access to property maintained.  Assumption that a signalized intersection at 7th and Main Street.  Assumption that right-of-way (ROW) widths documented in the FHWA 1998 ROD Memorandum Of Understanding.  Assumption that abandoned portion of SH 82 west of Cemetery Lane is converted to open space.  Assumption that both Marolt Trail and Holden Museum access road route up and over the cut-and-cover tunnel. Similarly, for the Splitshot alternative, designers replicated the couplet option documented in the 1995 DEIS. The alignment with profile was established similar to the 43 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 2 Phased PA, then modeled in Civil3d with a narrower platform width across the Marolt-Thomas property and Castle Creek. The following is the approach:  Utilizing narrower platform widths for eastbound.  Establishing a modified-direct alignment with profile for eastbound traffic from SH 82 east of the roundabout to 7th and Main Street. - Westbound (out of town) would follow the existing alignment that exists today. - Assumes profile for cut-and-cover and bridge would need to be optimized in later engineering stages, which could result in different impacts.  Modeling the alternative in Civil3d to for narrower one-way platform widths. Refer to Figure 6 in the main memorandum. Bridge platform width (49 feet) includes a sidewalk and shoulders.  Considerations that an LRT component could be provided for in the future.  Consideration that a transportation easement exists for a future roadway.  Consideration that the Berger Cabin at 835 West Main Street is to be relocated in accordance with the ROD (FHWA 1998) and access to property maintained.  Assumption that a signalized intersection at 7th and Main Street, with some access restrictions.  Preserving one-way local traffic and modified parking on the north side of West Main Street.  Considerations for some S-curve softening and resetting of east curb line along North 7th Street to facilitate movements.  Assumption that narrower ROW widths that are proportional to the platform widths.  Assumption that removal of Cemetery Lane traffic signal and traffic travels one-way west to roundabout to turn around and go east into town.  Assumption that both Marolt Trail and Holden Museum access road route up and over the cut-and-cover tunnel.  Assumption that westbound traffic use of existing Castle Creek Bridge with no bridge modifications. For the Three-lane Shifted bridge, the alternative is a combination of the S-curve improvements that tie into a three-lane bridge (one eastbound lane and two westbound lanes). The outside westbound lane is a dedicated bus that continues into a bus bypass lane that skirts along the golf course property and merges back into SH 82 approximately 1,400 feet west of the center of the roundabout. The following is the approach: 44 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 3  Establishing a bus bypass alignment with profile from SH 82 east of the roundabout to 7th and Main Street. - Assumes SH 82 on existing alignment west of Cemetery Lane. - Assumes S-curve widening and one general purpose and one bus rapid transit (BRT) lane in each direction.  Modeling the alternative in Civil3d for platform widths. Bridge platform width (52 feet) includes a sidewalk and shoulders.  Assumes widening SH 82 intersection with Cemetery Lane. - Intersection is signal controlled. - Some widening to the south side of SH 82 impacting Marolt-Thomas open space  Assumes Golf Course Trail relocated parallel and offset from bus bypass lane (Figure 10).  Assumes pedestrian undercrossing west of roundabout is extended to facilitate bypass lane. - Assumes westbound bus stop relocated 400 feet west.  Pushes westbound general traffic outside lane merge 400 feet.  Assumes some modifications to the Golf Course are required to keep playable (moving tee boxes and repositioning greens and sand traps).  Considerations that an LRT component could be provided for in the future.  Elevated risk of potential full ROW take for property below the Three-lane Shifted bridge. An existing ground surface was generated from light detection and ranging (LiDAR) surface data (courtesy of Pitkin County) and supplemented with field survey in the touchdown area, noted as top of east Castle Creek bank to 7th Street and West Main Street intersection. For each alternative, roadway cross-section elements were generated at specific intervals along the alignment to determine the impact of the cross sections on the existing surface and thereby determine a footprint for the alternative. Basically, identify the extents of cut and fill limits along each roadway corridor to estimate and compare relative impacts of each alternative. Conceptual Bridge Design Conceptual bridge design identifies the basic footprint of the bridge, potential limits for construction impacts, and the approximate span configuration for the bridge length. Feasible structure types are also identified, although a recommended structure type is not provided at this stage. 45 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives 4 For the Phased PA and Splitshot alternatives, the following considerations shape the conceptual bridge layout:  Steep terrain, influencing the bridge length and site impacts  Construction access to build the bridge, including a construction access road to build the piers  Castle Creek waterway, which is located under the middle of the bridge length  Construction methods, with a focus on methods that reduce site impacts The conceptual bridge length is approximately 525 feet for both alternatives. The conceptual layout presents a three-span bridge with the following features:  Longer spans to reduce the number of piers required within the steep slopes  Two piers that straddle Castle Creek to minimize permanent waterway impacts  A construction access road with switchbacks and two creek crossings to accommodate large construction equipment for the pier construction along the steep slopes. With longer spans and the desire to reduce site impacts, two structure types and construction methods are the most desirable: (1) concrete segmental bridge or (2) incremental launch steel bridge. Concrete segmental bridge construction is performed above the site, greatly reducing site impacts. Similarly, an incremental launch for a steel bridge allows construction to happen above the site. An incremental launch is also considered an accelerated bridge construction (ABC) method. For both methods, the foundations, piers, and abutments are built from the ground, and all other work is performed from above the site. Other construction methods require large cranes on the site, increasing the site impacts to provide the crane access and mobility and accommodate the crane pads. To further reduce site impacts, only complex bridge types can span the entire canyon. A single tower cable stayed bridge is an example of a complex bridge type for this site. Although this eliminates the need for piers under the bridge, cranes would still be required for part of the construction, creating temporary impacts. The complex nature also significantly increases project costs, and this option was not provided as a “typical” solution. Conceptual bridge layouts for the Phased PA and the Splitshot alternatives are shown in Attachments 2 and 3, with both a concrete segmental bridge and a steel bridge type shown for envisioning how the bridge would look. A feasible construction access road depicts a path that construction equipment takes for pier construction, using a maximum grade of 10%. Temporary impacts to the trees and vegetation along this access road will occur. The conceptual bridge layout for the Three-lane Shifted, along with other three- lane options, was previously described in the Feasibility Study (Jacobs 2024a). 46 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives Attachment 2: Phased PA Bridge Concept 47 114+00 115+00 116+00 117+00 118+00 119+00 120+00 All seals for this set of drawings are applied to the cover page(s) $$FILES$$ $$DATE$$ Date Comments Init. No Revisions: Revised: Void:Sheet Subset: Detailer: Designer: Sheet Number 2023-218 Project No./CodeSH82 over Castle Creek Bridge BRIDGE Subset Sheets: of Structure Numbers Print Date: File Name: Horiz. Scale:AS NOTED EL 7870 EL 7860 EL 7850 EL 7840 EL 7830 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7980 EL 7970 EL 7870 EL 7860 EL 7850 EL 7840 EL 7830 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7980 EL 7970 ELEVATION SCALE: 1" = 50' PLAN SCALE: 1" = 50' ALTERNATIVE - PHASE PA GENERAL LAYOUT 157'-6"210'-0"157'-6" 525'-0"73'-0" Out-to-Out36'-6"6'-0"Shldr6'-0"Shldr10'-0"Median1'-6" BridgeRail Type 92 Lanes @12'-0" = 24'-0"2 Lanes @12'-0" = 24'-0"1'-6" BridgeRail Type 936'-6"210'-0"157'-6"157'-6" 525'-0" Finished Grade Approach Slab (Typ) Expansion Jt Sleeper Slab (Typ) BF Abut 1 C Pier 2L C Abut 1L C Abut 4L C Pier 3L Existing Grade Castle Creek E F F E BF Abut 4 C Abut 1L C Abut 4L C Pier 2L C Pier 3L BF Abut 1 HCL BF Abut 4 20'-0" Approach Slab (Typ) 90°0'0" (Typ) To Aspen To Glenwo o d Springs S 74°40'46" E Expansion Jt C a s t l e C r e e k EL 7870 EL 7860 EL 7850 EL 7840 EL 7830 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7980 EL 7970 EL 7870 EL 7860 EL 7850 EL 7840 EL 7830 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7980 EL 7970 ELEVATION SCALE: 1" = 50' 157'-6"210'-0"157'-6" 525'-0" Finished Grade Approach Slab (Typ) Expansion Jt Sleeper Slab (Typ) BF Abut 1 C Pier 2L C Abut 1L C Abut 4L C Pier 3L Existing Grade Castle Creek E F F E BF Abut 4 Expansion Jt EL 7870 EL 7860 EL 7850 EL 7840 EL 7830 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7980 EL 7970 EL 7870 EL 7860 EL 7850 EL 7840 EL 7830 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7980 EL 7970 157'-6"210'-0"157'-6" 525'-0" Finished Grade Approach Slab (Typ) Expansion Jt Sleeper Slab (Typ) BF Abut 1 C Pier 2L C Abut 1L C Abut 4L C Pier 3L Existing Grade Castle Creek E F F E BF Abut 4 Expansion Jt EL 7870 EL 7860 EL 7850 EL 7840 EL 7830 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7980 EL 7970 EL 7870 EL 7860 EL 7850 EL 7840 EL 7830 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7980 EL 7970 157'-6"210'-0"157'-6" 525'-0" Finished Grade Approach Slab (Typ) Expansion Jt Sleeper Slab (Typ) BF Abut 1 C Pier 2L C Abut 1L C Abut 4L C Pier 3L Existing Grade Castle Creek E F F E BF Abut 4 Expansion Jt 48 $$PLOT_INFO$$All seals for this set of drawings are applied to the cover page(s) $$FILES$$ $$DATE$$ Date Comments Init. Sheet Revisions As Constructed No Revisions: Revised: Void:Sheet Subset: Detailer: Designer: Sheet Number 2023-218 Project No./CodeSH82 over Castle Creek Bridge BRIDGE Subset Sheets: of Structure Numbers Print Date: File Name: Horiz. Scale:AS NOTED ALTERNATIVE - PHASED PA TYPICAL SECTION 1'-6" Bridge Rail Type 9 6'-0" Shldr 2 Lanes @ 12'-0" = 24'-0"10'-0" Median 2 Lanes @ 12'-0" = 24'-0"6'-0" Shldr 1'-6" Bridge Rail Type 9 36'-6"36'-6" 73'-0" Out-to-Out 3" HMA over Waterproofing (Membrane) Varies HCL Varies 2" Conduit for Future Use (Typ) TYPICAL SECTION Steel Girder Altenative 1'-6" Bridge Rail Type 9 6'-0" Shldr 2 Lanes @ 12'-0" = 24'-0"10'-0" Median 2 Lanes @ 12'-0" = 24'-0"6'-0" Shldr 1'-6" Bridge Rail Type 9 36'-6"36'-6" 73'-0" Out-to-Out 3" HMA over Waterproofing (Membrane) Varies HCL Varies 2" Conduit for Future Use (Typ) Post-tensioned Cast-in-Place Concrete Box Girder Steel I-Girder (Typ) TYPICAL SECTION Segmental Concrete Alternative 49 Castle Creek Bridge SH 82 Footprint and Sensitivity Analysis of Alternatives Attachment 3: Splitshot Bridge Concept 50 114+00 115+00 116+00 117+00 118+00 119+00 120+00 All seals for this set of drawings are applied to the cover page(s) $$FILES$$ $$DATE$$ Date Comments Init. No Revisions: Revised: Void:Sheet Subset: Detailer: Designer: Sheet Number 2023-218 Project No./CodeSH82 over Castle Creek Bridge BRIDGE Subset Sheets: of Structure Numbers Print Date: File Name: Horiz. Scale:AS NOTED EL 7870 EL 7860 EL 7850 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7870 EL 7860 EL 7850 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 PLAN SCALE: 1" = 50' ALTERNATIVE - SPLITSHOT GENERAL LAYOUT ELEVATION SCALE: 1" = 50' 157'-6"210'-0"157'-6" 525'-0" Finished Grade Approach Slab (Typ) Expansion Jt Sleeper Slab (Typ) BF Abut 1 C Pier 2L C Abut 1L C Abut 4L C Pier 3L Existing Grade Castle Creek E F F E BF Abut 4 Expansion Jt2 Lanes @12'-0" = 24'-0"1'-6" BridgeRail Type 91'-6" BridgeRail Type 96'-0"Shldr6'-0"Shldr10'-0"Sidewalk49'-0" Out-to-Out31'-6"17'-6"210'-0"157'-6"157'-6" 525'-0" C Abut 1L C Abut 4L C Pier 2L C Pier 3L BF Abut 1 HCL BF Abut 4 20'-0" Approach Slab (Typ) 90°0'0"(Typ) To Aspen To Glenwo o d Springs S 74°40'46" E C a s t l e C r e e k EL 7870 EL 7860 EL 7850 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7870 EL 7860 EL 7850 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 ELEVATION SCALE: 1" = 50' 157'-6"210'-0"157'-6" 525'-0" Finished Grade Approach Slab (Typ) Expansion Jt Sleeper Slab (Typ) BF Abut 1 C Pier 2L C Abut 1L C Abut 4L C Pier 3L Existing Grade Castle Creek E F F E BF Abut 4 Expansion Jt EL 7870 EL 7860 EL 7850 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7870 EL 7860 EL 7850 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 ELEVATION SCALE: 1" = 50' 157'-6"210'-0"157'-6" 525'-0" Finished Grade Approach Slab (Typ) Expansion Jt Sleeper Slab (Typ) BF Abut 1 C Pier 2L C Abut 1L C Abut 4L C Pier 3L Existing Grade Castle Creek E F F E BF Abut 4 Expansion Jt EL 7870 EL 7860 EL 7850 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 EL 7870 EL 7860 EL 7850 EL 7910 EL 7900 EL 7890 EL 7880 EL 7930 EL 7920 EL 7940 EL 7960 EL 7950 ELEVATION SCALE: 1" = 50' 157'-6"210'-0"157'-6" 525'-0" Finished Grade Approach Slab (Typ) Expansion Jt Sleeper Slab (Typ) BF Abut 1 C Pier 2L C Abut 1L C Abut 4L C Pier 3L Existing Grade Castle Creek E F F E BF Abut 4 Expansion Jt 51 All seals for this set of drawings are applied to the cover page(s) $$FILES$$ $$DATE$$ Date Comments Init. No Revisions: Revised: Void:Sheet Subset: Detailer: Designer: Sheet Number 2023-218 Project No./CodeSH82 over Castle Creek Bridge BRIDGE Subset Sheets: of Structure Numbers Print Date: File Name: Horiz. Scale:AS NOTED ALTERNATIVE - SPLITSHOT TYPICAL SECTION 1'-6" Bridge Rail Type 9 10'-0" Sidewalk 6'-0" Shldr 2 Lanes @ 12'-0" = 24'-0"6'-0" Shldr 1'-6" Bridge Rail Type 9 17'-6"31'-6" 49'-0" Out-to-Out Varies 1'-6" Bridge Rail Type 9 10'-0" Sidewalk 6'-0" Shldr 2 Lanes @ 12'-0" = 24'-0"6'-0" Shldr 1'-6" Bridge Rail Type 9 17'-6"31'-6" 49'-0" Out-to-Out Varies TYPICAL SECTION Segmental Concrete Alternative TYPICAL SECTION Steel Girder Alternative Post-tensioned Cast-in-Place Concrete Box Girder Steel I-Girder (Typ) 2" Conduit for Future Use (Typ) 2" Conduit for Future Use (Typ) Chain Link Fence (36 Inch Splash Guard) (Typ) Chain Link Fence (36 Inch Splash Guard) (Typ) HCL HCL 3" HMA over Waterproofing (Membrane) 3" HMA over Waterproofing (Membrane) 52 1 Memorandum Subject: Castle Creek Bridge Funding and Financial Assessment Project Name: New Castle Creek Bridge Investigative Study with Revised Scope (the Project) Attention: City of Aspen (the City) From: Jacobs Date: July 26, 2024 Copies to: Project File 1. Introduction This memorandum (memo) summarizes funding options and sources for replacing the Castle Creek Bridge. It also discusses financial implications for the City. Infrastructure funding and financing is complex; this memo provides a broad overview to aid Project decision making. The memo discusses the following:  Federal, state, and local funding and grant opportunities available to the City  Implications for bridge construction using City and/or state funds without dependence on federal funding  Processes and strategies to gain federal and state funding support  Environmental implications related to different funding sources  Financial implications of self-funding the bridge replacement and devolving this section of the state highway 2. Background and History The Entrance to Aspen Final Environmental Impact Statement (EIS) (CDOT 1997) and Record of Decision (ROD) (FHWA 1998), which include transportation improvements along State Highway (SH) 82 from Buttermilk to Rubey Park in downtown Aspen, were approved by the Federal Highway Administration (FHWA) in 1998. The Preferred Alternative (PA) identified in the 1998 ROD calls for rerouting SH 82 to connect to Main Street, which would be extended to the west and require construction of a new Castle Creek Bridge. Under the PA, the existing segment of SH 82 from Cemetery Lane to 7th and Main Street, including the existing Castle Creek Bridge, would become a local route. 53 Memorandum: Castle Creek Bridge Funding and Financial Assessment 2 The Colorado Department of Transportation (CDOT) and the City signed a Memorandum of Understanding (MOU), documented as Attachment A to the ROD (FHWA 1998), which could have financial implications for the existing bridge. In the MOU, CDOT commits to maintaining the existing Castle Creek Bridge for a 25-year period commencing after the construction of the Project segment from the Maroon and Castle Creek intersection to 7th and Main Street, when CDOT conveys the bridge to the City. This MOU could be interpreted as committing CDOT to fund, at least partially, future bridge improvements or replacement. Since the ROD was issued, several elements of the PA have been implemented. The portion of the PA from the Maroon and Castle Creek intersection to 7th and Main Street involving rerouting SH 82 and reconstructing a new bridge over Castle Creek remains to be completed. Because the National Environmental Policy Act (NEPA) process was completed, implementation of the remaining PA improvements would qualify for federal funding, provided that an EIS Reevaluation confirming that the ROD is valid is completed (refer to the NEPA Process Options memo completed for this Project for details [Jacobs 2024]). The existing Castle Creek Bridge, constructed in 1961, is now approaching the end of its service life. As discussed in Section 3.2 (State Funding), when the bridge condition is rated poor through CDOT inspections, it will enter the Statewide Bridge and Tunnel Enterprise eligibility pool for funding and replacement. At that time, CDOT has indicated that it would replace the bridge as directed in the PA, unless an alternative NEPA decision is made before the need for bridge replacement. The City has expressed interest in pursuing alternatives to the PA because of the impacts and divided community sentiment on the PA. In a letter dated July 10, 2024, CDOT indicated that a Supplemental EIS, at a minimum, would be required to change the PA and/or select another alternative. The letter further states that the City, as a cooperating agency to the EIS, can choose to no longer support the ROD, but unless FHWA and CDOT choose to withdraw the ROD, the ROD and the selected PA will remain in effect (CDOT, pers. comm. 2024c). Therefore, any change or deviation from the PA and ROD would require close coordination and agreement from FHWA and CDOT and would require coordination with other corridor stakeholders and interests. One option the City Council is evaluating is replacing the existing Castle Creek Bridge separately, or outside of, the Entrance to Aspen (ETA) process. In its letter dated March 20, 2023, CDOT indicated that the City would have to self-fund a new EIS/ROD, as state and federal funding has already been provided to complete the EIS/ROD and the required mitigation for the PA. In the same letter, CDOT indicated that the City “reviewing an alignment at the existing bridge location” would trigger a new EIS/ROD that would have to be funded locally (CDOT, pers. comm. 2024a). 54 Memorandum: Castle Creek Bridge Funding and Financial Assessment 3 3. Funding Opportunities Financing the construction, operation, and maintenance of public transportation systems involves many different types of funding sources, including federal and nonfederal grants, cooperative agreements, loans, and revenue sources. This section highlights several grant or formula programs that could be used to fund bridge replacement, categorized by federal, state, and local sources. 3.1 Federal Funding Opportunities Federal funding for transportation projects has increased in recent years with passage of the Bipartisan Infrastructure Law of 2021 and other related federal legislation. Table 1 lists some of the more relevant federal funding programs. 55 Memorandum: Castle Creek Bridge Funding and Financial Assessment 4 Table 1: Federal Funding Sources Program Name Description Minimum and Maximum Grant Awards Local Cost Share Requirement Funding Cycle Web Link to Program Information PROTECT Grant Program Provides funding for projects that increase the resilience of existing surface transportation assets Not applicable Up to 100% federal for planning grants; less than 80% federal share for construction grants FY24 program expected to be released in August 2024 PROTECT Grant Program link FLAP FHWA grant program that supports upgrades to transportation facilities that provide access to federal lands Planning grant:  Maximum: $10 million  Minimum: $100,000 Implementation grant:  Maximum: $25 million  Minimum: $2.5 million None; however, recommended for projects, such as Castle Creek Bridge, that are not on federal lands Additional funding expected to be released in 2025 FLAP link BIP  Supports bridge repair, rehabilitation, and replacement  Prioritizes bridges that are in Fair or Poor condition on the National Bridge Inventory  Planning grant: $20 million maximum  Construction grants: greater than $2.5 million 20% Annually; applications for FY25 funding are due on November 1, 2025 BIP link 56 Memorandum: Castle Creek Bridge Funding and Financial Assessment 5 Program Name Description Minimum and Maximum Grant Awards Local Cost Share Requirement Funding Cycle Web Link to Program Information RAISE Grant Program Supports the capital costs of road, rail, transit, and port projects that have a significant impact on the nation, region, or metropolitan area  Minimum: $5 million  Maximum: $25 million 20% Annually RAISE Grant Program link BIP = Bridge Investment Program FLAP = Federal Lands Access Program FY = fiscal year PROTECT = Promoting Resilient Operations for Transformative, Efficient, and Cost-saving Transportation RAISE = Rebuilding American Infrastructure with Sustainability and Equity 57 Memorandum: Castle Creek Bridge Funding and Financial Assessment 6 3.1.1 Federal Funding Considerations The Biden administration has focused their grants on an array of priorities, including the following:  Climate change  Environmental sustainability and projects that improve community resilience  Inclusion in a disadvantaged census tract  Equity issues These priorities would change with a change in presidential administration. Further, projects can sometimes be modified to better address federal grant criteria, and although the Project is not in a disadvantaged census tract, arguments can be made for improving conditions and reducing costs for disadvantaged populations through public transit improvements with a regional focus. Federal grants often rely on political support from the governor and congressional representatives. If the City were to pursue a federal grant, it should seek the support of these elected officials. Demonstrating a regional benefit from the Project, particularly for disadvantaged populations, would boost funding chances. Projects that receive federal funding are subject to NEPA requirements. For competitive grants (excluding planning grants), projects that have completed or are nearing completion of the NEPA process generally are viewed more favorably by federal reviewers. Also, in a meeting on July 10, 2024, between CDOT, City, and Jacobs staff, CDOT noted that, because a ROD is in place for the SH 82 corridor, any project that differs from the ROD PA may not be viewed favorably. 3.2 State Funding Opportunities Table 2 lists some of the more relevant state funding programs. 58 Memorandum: Castle Creek Bridge Funding and Financial Assessment 7 Table 2: State of Colorado Funding Sources Program Name Description Minimum and Maximum Grant Award Local Cost Share Funding Cycle Submission Deadline Web Link to Program Information CBTE The purpose of the CBTE is to finance, repair, reconstruct, and replace bridges designated as structurally deficient. Structural deficiency occurs when any structural element condition drops to a “poor” rating, associated with a condition code of 4 or less from that element’s inspection. CBTE prioritizes bridges based on criteria for safety and risk, mobility, and economic factors, along with acknowledgement of structures on CDOT’s 10-year Vision Plan.” In 2023 and 2024, over $165,000,000 is dedicated to bridge rehabilitation and replacement. No minimum or maximum award. Funding is based on sufficiency rating and importance and need. Planned replacements are included in CDOT’s 10-year Plan. The next planning phase is currently starting within the IMTPR. (CDOT 2024b). No local share Annually Not applicable Statewide Bridge and Tunnel Enterprise link 59 Memorandum: Castle Creek Bridge Funding and Financial Assessment 8 Program Name Description Minimum and Maximum Grant Award Local Cost Share Funding Cycle Submission Deadline Web Link to Program Information Department of Local Affairs Climate Resistance Challenge The Climate Resilience Challenge promotes and integrates climate resilience projects that capture multiple objectives across the following:  Climate adaptation  Climate mitigation solutions  Social equity by addressing the most high-risk vulnerabilities for their community or region These funds potentially could be used for roadway improvements that increase wildfire evacuation capacity. $2 million 25% for construction and 10% for planning Annually Opening July 1 and closing August 1 Climate Resilience Challenge link 60 Memorandum: Castle Creek Bridge Funding and Financial Assessment 9 Program Name Description Minimum and Maximum Grant Award Local Cost Share Funding Cycle Submission Deadline Web Link to Program Information MMOF The MMOF provides funding for an array of capital, construction, operations, planning, and greenhouse gas mitigation projects, including bicycle, pedestrian, ride sharing, or transit projects. The Local MMOF Program funds are distributed by formula among Colorado's 15 TPRs, who then award funding to projects competitively within their regions. Funding is allocated to the local TPRs through a percentage of annual revenue formula. The IMTPR is allocated $260,000 in 2024 but has allocations up to $800,000 in FY28. 50% from other sources, which can include other grants Annually The process is determined by the TPR MMOF link CDOT Revitalizing Main Streets Funding This program encourages physical activity and enhances local economic vitality in towns and cities across Colorado through funding infrastructure improvements to make walking and biking easier, yielding long-term benefits that bolster community connections. $10,000 to $250,000 10% of the total project cost Rolling application cycle, with six cycles in 2024 Next cycle on August 28, 2024 Revitalizing Main Streets link CBTE = Colorado Bridge Enterprise Fund IMTPR = Intermountain Transportation Planning Region MMOF = Multimodal Transportation and Mitigation Options Fund TPR = Transportation Planning Region 61 Memorandum: Castle Creek Bridge Funding and Financial Assessment 10 3.21 State Funding Considerations Because of the age and condition of the Castle Creek Bridge, the CBTE has received considerable discussion as a funding source. Formed in 2009 as part of the Funding Advancement for Surface Transportation and Economic Recovery (FASTER) legislation, the CBTE operates as a government -owned business within CDOT. Although $165 million is dedicated to the fund in 2023 and 2024, CDOT noted that large interstate projects, such as Floyd Hill, West Vail Pass, and Interstate 25 project, use much of this funding. A Castle Creek Bridge inspection is scheduled for fall 2024. If this inspection results in a structural element dropping to a “poor” rating, the bridge would be added to a statewide list and prioritized based on the bridge rating as well as overall importance to the transportation system. When funding becomes available and CDOT and CBTE agree that this bridge is this their highest priority, CDOT has indicated they would be required to build the PA under the ROD unless another alternative was selected as part of a supplemental or new NEPA process. State funding would require review and prioritization by the IMTPR. The Project would need to be rereviewed and prioritized by the IMTPR to be positioned for state funding through CDOT’s 10-year prioritization plan (CDOT 2024b). The PA is within the current regional long-range plan. CDOT noted that demonstrating political consensus for an alternative through a support resolution and/or advocacy from political representatives attending the IMTPR would increase the likelihood of IMTPR support and prioritization. The state transportation commission is considering splitting the IMTPR, with Garfield and Pitkin separating from Eagle and Summit counties. No new funding would be generated, but the region’s priorities could be easier to develop with less competition from Summit and Eagle counties. Regarding environmental considerations and as noted previously, the ETA ROD remains in place on this portion of SH 82 and, therefore, any new alternative or project needs to be considered in relation to the ROD. Further, state-funded projects that do not have a federal component are subject to CDOT’s requirements. CDOT’s Environmental Stewardship Guide states that CDOT generally follows the NEPA process for state -funded projects (CDOT n.d.). Technical reports are prepared for relevant resources and are reviewed by CDOT resource leads. Public and stakeholder engagement follows a similar process to federally funded projects. FHWA would not be involved unless there is a federal nexus. Some federal laws are not applicable to state-funded projects. For example, Section 4(f) of the Department of Transportation Act, Section 106 of the National Historic Preservation Act (NHPA), and the Farmland Protection Policy Act only apply to projects 62 Memorandum: Castle Creek Bridge Funding and Financial Assessment 11 with federal funding and/or a federal nexus. State-funded projects must still comply with many other federal laws, including the following:  Clean Water Act  Clean Air Act  Endangered Species Act  Migratory Bird Treaty Act  Section 6(f) of the Land and Water Conservation Act State-funded projects are also subject to state and local regulations. State laws require consideration of impacts to riparian areas and hazardous materials handling and waste management. Additionally, CDOT follows a process similar to NHPA Section 106 to assess and mitigate potential effects to historic properties nominated or listed on the State Register of Historic Properties. Beyond state requirements, local ordinances and permitting requirements apply to floodplain development and may control other Project effects on the community, such as construction noise and effects on local historic landmarks. 3.3 Local Funding Opportunities Local funding sources could be used, including providing matching funds for state and federal grants. Some local funding sources include the following:  The Elected Officials Transportation Committee (EOTC) has a dedicated local tax funding mechanism that could help fund transit improvements. The EOTC was originally set up to facilitate funding for the 1998 ETA ROD.  The Roaring Fork Transportation Authority may be willing to consider a joint tax measure with the City to help fund any Project transit improvements.  The City could pass a dedicated tax or Special District Assessment for the Project. Using utility enterprise funds to partially support utility upgrades or line replacements in a larger tax-funded capital project also could be explored. These local funds can be used as matching funds for a larger grant. 4. The City’s Finance Department confirmed that there is no local funding allocated in the Asset Management Plan, and further, the fund is strained to meet current needs identified in the annual city budget development process.Financial Implications for Self-funding The 2024 estimate for the Three-Lane Shifted bridge alternative is $69 million. This cost escalates to $81 million in 2028. These estimates include known right of way costs as of 63 Memorandum: Castle Creek Bridge Funding and Financial Assessment 12 April 2024. However, there is a risk of additional right of way cost, in that the Three-Lane Shifted bridge option lies less than 2 horizontal feet from a physical residence below the bridge. Due to proximity and safety concerns during construction, there is a high probability that this property would need to be acquired. For comparison, the estimated cost of the Preferred Alternative was $102 million in 2016 and would be much higher today. If Aspen proceeds with the PA, it will be able to compete for Federal and State grants and access to prioritization under the CBTE fund, lowering the overall cost to the community, perhaps substantially. As an example, CDOT replaced the Glenwood Springs Grand Avenue Bridge in 2017 at an approximate cost of $120 million. The city and the county each contributed $3 million. Private utility companies paid for the construction of the pedestrian bridge (approximately $17 million). The balance of the project came from CDOT CBTE funding. A high-level review of Aspen’s 2024 budget (City 2023) indicates that just over $45 million is allocated to capital improvements. However, many of these appropriations are restricted for a particular use, such as affordable housing. For this reason, funding the bridge replacement and other ETA improvements with City funds is not feasible without tax measures that would allow bonding for the Project. Table 3 shows budget appropriations. Restricted budgets are marked with an asterisk. A double asterisk indicates that some projects are paid for with dedicated funding streams. Table 3: City of Aspen Capital Budget for 2024 Fiscal Year Fund Capital Project 2024 Appropriation Lifetime Budget Affordable Housing* Lumber Yard Housing Development – Phase 0 $14,250,000 $14,250,000 Asset Management Plan Old Powerhouse Preservation Project $3,845,000 $4,445,000 Water Utility* Water Treatment Facility Improvements $3,600,000 $15,392,000 Parks and Open Space* Parks Site Interior $3,100,000 $3,500,000 Electric Utility* Paepcke Park to City Market Circuit Replacement $2,550,000 $2,550,000 Employee Housing* Main Street Cabin Housing $2,409,750 $2,724,750 Asset Management Plan Fleet – 2024 $1,144,000 $1,144,000 64 Memorandum: Castle Creek Bridge Funding and Financial Assessment 13 Fund Capital Project 2024 Appropriation Lifetime Budget Asset Management Plan Armory Remodel and Reuse Long-term Plan $920,000 $1,020,000 Asset Management Plan Red Brick Storm Improvements on Hallam Street $760,000 $760,000 Stormwater* Garmisch Street Pipe Repair and Replacement $700,000 $2,261,557 Asset Management Plan Concrete and ADA Pedestrian Improvements – 2024 $656,000 $656,000 Housing* Building Envelope Improvements and Water Proofing $640,000 $800,000 Transportation* Shuttle Replacement – 2024 $552,000 $552,000 Asset Management Plan Animal Shelter – Energy Efficiency Upgrades $450,000 $500,000 Asset Management Plan Highway 82 Efficiency Planning $400,000 $400,000 Parks and Open Space* AIG Cooling Tower Replacement $375,000 $375,000 Asset Management Plan Hyman Improvements $350,000 $350,000 Parks and Open Space* Maroon Creek Road Trail – Construction $315,000 $4,565,000 Parking* Downtown Core Parking Improvements $300,000 $1,900,000 Wheeler* Theatre Sound System Replacement $290,000 $500,000 Parks* AABC to Brush Creek Park and Ride Trail Connection Contribution $250,000 $4,250,000 Various ** Remaining projects less than $250,000 $5,129,220 $14,383,030 Various ** Capital maintenance $2,652,260 $27,035,830 Total capital Not applicable $45,638,230 $104,314,167 Source: City, 2023. AABC = Aspen Airport Business Center 65 Memorandum: Castle Creek Bridge Funding and Financial Assessment 14 ADA = Americans with Disabilities Act 5. State Highway Devolution and Implications Devolution refers to the transference of a highway or segment of highway from state ownership and control to local government ownership and control. Some communities consider state right-of -way devolution to gain control of access, beautification, and maintenance decisions within their jurisdictions. Devolution has been mentioned in relation to the ETA and bridge replacement as a potential means to give the city greater control over decision making on the SH 82 corridor. Because of state budget shortfalls and maintenance burdens, CDOT will usually engage in devolution discussions. CDOT’s letter from July 10, 2024, states that devolution is possible but would require having reasonable highway limits like the city boundaries, versus limits that only include the bridge and its approaches. The letter notes that “even if the City takes over ownership of a portion of SH 82, the ROD will remain in effect as the decision made was not predicated on the road being a State Highway” (CDOT, pers. comm. 2024c). The financial burden of obtaining portions of state highway through devolution typically exceeds the funding received from CDOT. Signal maintenance is one such example. Although devolution was not needed for the City to gain control of their signal operation to retime the signals to prioritize pedestrians over vehicle clearance on the highway, CDOT transferred the operation of the signals to the City in October 2021. According to City staff, maintenance of the signals requires considerable staff time. Further, the 2018 CDOT payment for signal maintenance did not consider a net present value for the full 5-year period and thus does not fully cover the expense. Benefits of devolution for local jurisdictions include the following:  Control over physical improvements design and construction decisions  Control over maintenance decisions  Control of local access  Ability to add traffic-calming or beautification improvements without state input  State cash contribution to future maintenance Disadvantages of devolution for local jurisdictions include the following:  Responsibility for all future road maintenance  Responsibility for accident prevention and solutions  Responsibility for operations and signals 66 Memorandum: Castle Creek Bridge Funding and Financial Assessment 15 6. Conclusions Considering the high Project costs, the fiscal implications of self-funding, and CDOT’s direction that the selected PA will remain in effect, the City should consider working with CDOT and FHWA on next steps for the ETA. Next steps include either initiating a Supplemental EIS or implementing the Preferred Alternative. Working within the CDOT framework will allow the city to access federal and state funding streams to offset the cost to the community. 7. References City of Aspen (City). 2023. 2024 Proposed Budget. September 25. https://www.aspen.gov/DocumentCenter/View/11394/2024-Proposed-Budget--- Digital-Book-PDF. Colorado Department of Transportation (CDOT). 1997. State Highway 82 Entrance to Aspen: Final Environmental Impact Statement, Section 4(f), Volume I. Project STA 082A-008. August. Colorado Department of Transportation (CDOT). 2024a. Personal communication (letter) with the City of Aspen. March 20. Colorado Department of Transportation (CDOT). 2024b. Vision for Colorado's Transportation System: Updated 10-year Strategic Project Pipeline. May. https://www.codot.gov/programs/planning/assets/may2024_cdot_ytp_10yearvision_c ombined-june-3-2024-final.pdf. Colorado Department of Transportation (CDOT). 2024c. Personal communication (letter) with the City of Aspen. July 10. Colorado Department of Transportation (CDOT). n.d. Environmental Stewardship Guide. Accessed July 2024. Federal Highway Administration (FHWA). 1998. State Highway 82 Entrance to Aspen: Record of Decision. Project STA 082A-008. August. https://www.codot.gov/projects/archived-project- sites/SH82/documents/1998ROD.pdf. Jacobs. 2024. Castle Creek Bridge NEPA Process Options. Prepared for the City of Aspen. April. 67 Memorandum: Castle Creek Bridge Operational Traffic Analysis 1 Memorandum Subject: Castle Creek Bridge Operational Traffic Analysis Project Name: New Castle Creek Bridge Investigative Study with Revised Scope (the Project) Attention: City of Aspen (the City) From: Jacobs Date: July 31, 2024 Copies to: Project File 1. Introduction This memorandum evaluates traffic impacts of the roadway improvement alternatives under consideration, which generally improve traffic and transit operations. The study area is depicted on Figure 1, primarily following Colorado State Highway (SH) 82 on the west side of Aspen, Colorado. The study area is subject to recurring congestion throughout the week, particularly heavy during weekday peaks (morning and afternoon), which the Project aims to improve for general traffic and transit. A traffic model was prepared for this study using PTV Vissim software (Version 2024), a traffic microsimulation software that produces realistic visual demonstrations and performance measures of varying traffic operational scenarios. The eastbound travel direction on Castle Creek Bridge will be referred to as “inbound” (into Aspen), and the westbound travel direction on Castle Creek Bridge will be referred to as “outbound” (out of Aspen). Similarly, the southbound SH 82 travel direction (that is, up-valley) will be referred to as “inbound,” and northbound SH 82 (that is, down- valley) will be referred to as “outbound.” 2. Methodology The analysis focuses on two peak hours for traffic demand – one for inbound traffic and one for outbound traffic. 2.1 Traffic Count Data Traffic data were collected on Tuesday, May 21, 2024. Automatic traffic recorder counts were collected on Castle Creek Bridge for 24 hours, and turning movement counts (TMCs) were collected using video cameras at 21 study intersections during known traffic peak periods of 7:30 to 9:30 a.m. and 4:00 to 6:00 p.m. on weekdays. The 21 study intersections are shown on Figure 1. 68 Memorandum: Castle Creek Bridge Operational Traffic Analysis 2 Figure 1: Study Area 69 Memorandum: Castle Creek Bridge Operational Traffic Analysis 3 All data were provided in 15-minute increments. TMC data were provided with three vehicle classifications: (1) light vehicles, (2) medium vehicles, and (3) articulated trucks. 2.2 Peak-hour Identification Traffic peak hours were determined using the directional bridge volumes and peak period TMCs. The inbound peak hour on Castle Creek Bridge was found to be 8:15 to 9:15 a.m., and the outbound peak hour was identified as 4:30 to 5:30 p.m. These peak hours matched the majority of peak hours at the 21 study intersections. 2.3 Traffic Volume Adjustment (May to July) Monthly traffic data on Castle Creek Bridge from1999 to 2023 (McGowan, pers. comm. 2024) indicate that July typically has the highest traffic volumes of any month. To represent the true traffic peak in Aspen, traffic volumes were adjusted from May to July. In 2023, July daily traffic was 37% higher than May. However, peak-hour traffic in July is not expected to be 37% higher than peak-hour traffic in May because of limited roadway capacity during the peak-hour. This phenomenon is known as “peak spreading,” which features longer traffic peak durations in July compared to May. Hourly traffic data were obtained from Colorado Department of Transportation’s (CDOT’s) Online Transportation Information System (OTIS) (CDOT n.d.) at the nearest location of continuous daily traffic counter (Station 000236) located SH 82 near Snowmass Creek Road. At this location, peak-hour traffic in July was found to be 8.3% higher during the morning peak and 17.3% higher during the evening peak when compared to May. These factors were applied to the traffic data collected in May to estimate traffic data in July, with one exception on Maroon Creek Road due to the presence of schools, which are out of session in July. Using StreetLight data (StreetLight n.d.), it was determined that peak-hour traffic should be decreased by 20% on Maroon Creek Road to adjust from May to July. 2.4 Traffic Signals The study area includes six signalized intersections, all located along SH 82 at the following cross streets: 1) Brush Creek Road 2) Aspen Airport Business Center 3) Harmony Road 4) Owl Creek Road 5) Truscott Place 6) Cemetery Lane All traffic signals are owned and maintained by CDOT, who provided signal timing information for this study (Staley, pers. comm. 2024). 70 Memorandum: Castle Creek Bridge Operational Traffic Analysis 4 2.5 Traffic Growth Jacobs reviewed the Entrance to Aspen Record of Decision (ROD) (FHWA 1998) and bridge traffic data between 1993 and 2023. The highest average daily traffic (ADT) was measured in July 1993, which was the community goal to maintain in the ROD. Assuming that July 1993 is the highest feasible ADT for Castle Creek Bridge in 2050, a growth rate of 1.09% (from 2023 to 2050) was back calculated to reach 1993 ADT levels in the analysis year (2050). Jacobs reviewed CDOT's OTIS (CDOT n.d.) at traffic count stations surrounding Castle Creek Bridge (Stations 103524 and 103528). Both stations were found to have an annual growth rate of 0.45%. Considering annual growth rates obtained from OTIS and 1993 bridge ADT, a recommended growth rate should be between these values. To be conservative, leaning toward the higher growth, an annual growth rate of 1.00% for ADT is recommended for this study. Because of peak-hour roadway capacity constraints, peak hours cannot accommodate as much traffic as off-peak hours (that is, peak spreading), so a reduced growth rate is recommended for peak hour analysis. A 25% reduction was selected based on engineering judgement, and an annual growth rate of 0.75% for peak hours is recommended for this study. Traffic growth is applied linearly in this study and is not compounded annually. 2.6 Analysis Scenarios This study analyzed the scenarios listed below. Option 2 includes an additional outbound transit lane, which has been discussed in association with three-lane options to replace the existing Castle Creek bridge. Options 3 and 4 were alternatives studied in the Entrance to Aspen EIS. Different options include varied improvements to improve SH 82 traffic flow.  Option 0: No Build  Option 1: S-curve Improvements  Option 2: Outbound Transit Improvements  Option 3: Phased Preferred Alternative (PA)  Option 4: Splitshot  Option 5: Down-valley Improvements The following scenarios were evaluated as described: 1) Existing (2024) for purposes of calibration 71 Memorandum: Castle Creek Bridge Operational Traffic Analysis 5 2) Operational (2050) a) Option 0: No Build  Applies 0.75% annual growth to traffic demand into the study network b) Option 1: S-curve Improvements  Adds bus lane in each travel direction through the SH 82 S-curves  Eliminates the southbound approach of North 7th Street onto SH 82  Eliminates the wastbound left turn from SH 82 to 7th Street  Eliminates the eastbound left turn from SH 82 to North 8th Street  Eliminates the westbound right turn from SH 82 to North 8th Street  Eliminates the movements from SH 82 to West Main Street and South 7th Street  Option 1A: Maintains the southbound approach of North 8th Street onto SH 82  Option 1B: Eliminates the southbound approach of 8th Street onto SH 82 c) Option 2: S-curve Improvements with Outbound Bus Improvements  Includes all features described in Option 1  Introduces one additional lane on Castle Creek Bridge as an outbound bus lane  Option 2A: Introduces an outbound bus queue jump for the SH 82 signal at Cemetery Lane  Option 2B: Introduces an outbound bus bypass at the SH 82 roundabout d) Option 3: Phased PA (Bus Transit)  Modifies the SH 82 alignment to cross the Marolt-Thomas property parallel to Hallam Street, including one general purpose lane and one bus lane in each direction  Removes the existing SH 82 roadway section between Maroon Creek Road and Cemetery Lane  Removes the existing signal at Cemetery Lane and converts the intersection into a free-flow section  Adds a signalized intersection at West Main Street and North 7th Street e) Option 4: Splitshot  Modifies the SH 82 inbound alignment to cross the Marolt-Thomas property parallel to Hallam Street, including one general purpose lane and one bus lane 72 Memorandum: Castle Creek Bridge Operational Traffic Analysis 6  Converts the existing SH 82 alignment to one-way between Maroon Creek Road and 7th Street, which includes one general purpose lane for the outbound direction and one bus lane  Removes the existing signal at Cemetery Lane and converts the intersection into a right-in/right-out roadway  Adds a signalized intersection at West Main Street and North 7th Street f) Option 5: Down-valley Improvements  Includes all features described in Option 1A (S-curve widening and intersection access restrictions)  Channelizes the outside lane of the westbound (outbound) movement at the Maroon Creek roundabout by adding a barrier between lanes  Removes 0.38 mile of the dedicated northbound (outbound) bus lane on SH 82 between Truscott Lane and Maroon Creek roundabout  Introduces 0.38 mile of the dedicated southbound (inbound) bus lane on SH 82 between the Airport Business Center and Service Center Road  Increases the maximum green time for the left turn from Brush Creek Road to outbound SH 82 from 15 seconds to 20 seconds Construction analysis year 2028 was selected for the construction year traffic analysis. Design year 2050 was selected as the planning horizon year, slightly more than 20 years after Project completion. 2.7 Measures of Effectiveness This study uses the following measures of effectiveness to evaluate traffic impacts:  Vehicular travel time (in minutes or hours) along SH 82, which was measured between the study area extents of Brush Creek Road and 5th Street, a roughly 5.5-mile section (Figure 1)  Transit travel time (in minutes) along SH 82 across the same 5.5-mile section  Total roadway network delay, that is congestion (in vehicle-hours of delay) within the study area  Throughput (in vehicles) across SH 82 on Castle Creek Bridge 3. Traffic Modeling Results This section describes operations under each analysis scenario. The discussion is based on the travel time results and overall roadway delay results provided on Figures 2 through 5. 73 Memorandum: Castle Creek Bridge Operational Traffic Analysis 7 General traffic and transit travel times are different due to dwell time at bus stops and exclusive bus-only lanes to bypass peak-hour queues. Bridge throughput is represented as SH 82 bridge throughput. For Option 3, the Phased PA, this means only traffic crossing the new Castle Creek Bridge. For Option 4, Splitshot, this would be traffic that crosses the new Castle Creek Bridge and the bridge on existing SH 82. Options 1A, 1B, and 2A contain similar operations during the AM peak, as explained later in this section. Figure 2: Outbound Travel Times  Option 0: No Build  Option 1: S-curve Improvements  Option 2: Outbound Transit Improvements  Option 3: Phased Preferred Alternative (PA)  Option 4: Splitshot  Option 5: Down-valley Improvements 74 Memorandum: Castle Creek Bridge Operational Traffic Analysis 8 Figure 3: Inbound Travel Times  Option 0: No Build  Option 1: S-curve Improvements  Option 2: Outbound Transit Improvements  Option 3: Phased Preferred Alternative (PA)  Option 4: Splitshot  Option 5: Down-valley Improvements 75 Memorandum: Castle Creek Bridge Operational Traffic Analysis 9 Figure 4: Total Roadway Network Delay  Option 0: No Build  Option 1: S-curve Improvements  Option 2: Outbound Transit Improvements  Option 3: Phased Preferred Alternative (PA)  Option 4: Splitshot  Option 5: Down-valley Improvements 76 Memorandum: Castle Creek Bridge Operational Traffic Analysis 10 Figure 5: SH 82 Bridge Throughput  Option 0: No Build  Option 1: S-curve Improvements  Option 2: Outbound Transit Improvements  Option 3: Phased Preferred Alternative (PA)  Option 4: Splitshot  Option 5: Down-valley Improvements 3.1 Existing Conditions The following is an overview of how existing conditions in the peak hours operate today. 3.1.1 Morning Peak Hour The inbound direction’s peak hour contains several bottlenecks along SH 82 within the study network. The first bottleneck is located 0.2 mile north of the SH 82 intersection at Harmony Road, where there is a reduction from two general traffic lanes to one lane. This bottleneck generates the longest and slowest-moving queue along the inbound route. The next bottlenecks along SH 82 are less severe and include the roundabout at Maroon Creek Road, the signal at Cemetery Lane, and the free right turn from Hallam Street to 7th Street. Further upstream of the free right turn, the model shows that traffic flows relatively uninterrupted into Downtown Aspen. 77 Memorandum: Castle Creek Bridge Operational Traffic Analysis 11 The inbound peak-hour queue on SH 82 extends from 7th St to the north side of the Aspen-Pitkin County Airport. On average during the morning peak hour, it takes 32 minutes for general traffic to travel 5.5 miles on SH 82 from Brush Creek Road to 5th Street. 3.1.2 Evening Peak Hour The outbound direction’s peak hour also contains several bottlenecks along SH 82 within the study network. The first bottleneck is located between 5th Street and 6th Street, where there is a reduction from two general traffic lanes to one lane. The next bottlenecks along SH 82 include the free right turn from Main Street to 7th Street, the free left turn from 7th Street to Hallam Street, the signal at Cemetery Lane, the roundabout at Maroon Creek Road, and the reduction from two general traffic lanes to one located 0.1 mile north of the roundabout at Maroon Creek Road. Further downstream, traffic congestion is limited to typical traffic signal delay. All bottlenecks mentioned previously contribute to the slow travel speeds experienced throughout Downtown Aspen during the evening peak hour. On average during the evening peak hour, it takes 14 minutes for general traffic to travel 5.5 miles on SH 82 from 5th Street to Brush Creek Road. 3.2 No Build (2050) Conditions The following is an overview of how a future condition with no improvements and traffic growth in the year 2050 will operate in the peak hours. 3.2.1 Morning Peak Hour Under No Build conditions, the inbound peak-hour queue on SH 82 extends roughly 2 miles further north, beyond Brush Creek Road and the edge of the study network. At the beginning of the peak hour, approximately 20% more vehicles travel through this very long queue. In 2050, travel times roughly double from Existing to No Build. 3.2.2 Evening Peak Hour Under No Build conditions, the outbound peak queue on SH 82 extends east beyond 5th Street into Downtown Aspen. This delay (backup into downtown and throughout the west end neighborhoods) is captured as overall network delay but is not captured in travel times from 5th Street to Brush Creek Road. This means that, in 2050, more vehicles wait to access the highway system on the neighborhood streets and on SH 82 beyond 5th Street, but once they reach 5th Street or enter the highway at another location, the travel time between 5th Street and Brush Creek Road remains comparable to the morning peak hour. 78 Memorandum: Castle Creek Bridge Operational Traffic Analysis 12 3.3 Option 1A: S-curve Improvements with 8th Street Access to SH 82 The following is an overview of how the S-curve improvements with 8th Street outbound access and a future traffic year of 2050 will operate in the peak hours. 3.3.1 Morning Peak Hour In Option 1A, inbound peak-hour traffic and transit operations remain relatively the same. Although inbound general traffic travel times decrease by 2 minutes, overall traffic congestion increases by 11% compared to the No Build. 3.3.2 Evening Peak Hour In Option 1A, outbound peak-hour travel times for general traffic remain similar to the No Build. Outbound bus delay is reduced by 2 minutes due to the new bus lane through the S-curve. Overall network congestion increases by 2% compared to the No Build. 3.4 Option 1B: S-curve Improvements with no 8th Street Access to SH 82 The following is an overview of how the S-curve improvements with no 8th Street outbound access and a future traffic year of 2050 will operate in the peak hours. 3.4.1 Morning Peak Hour The removal of 8th Street access is not anticipated to impact morning peak-hour operations. Result from Option 1A apply to Option 1B. 3.4.2 Evening Peak Hour The removal of 8th Street access increases overall network congestion by 1% compared to maintaining 8th Street access. This finding suggests that 8th Street access should be maintained. 3.5 Option 2A: S-curve Improvements with Outbound Bus Lane with Bus Queue Jump for the SH 82 Signal at Cemetery Lane The following is an overview of how the S-curve improvements with a transit priority queue jump at the Cemetery Lane signal will operate in the peak hours in the year 2050. 3.5.1 Morning Peak Hour In Option 2A, inbound peak-hour traffic and transit operations remain relatively the same. Although general traffic travel times decrease by 4 minutes, overall network congestion increases by 30% compared to the No Build. 79 Memorandum: Castle Creek Bridge Operational Traffic Analysis 13 3.5.2 Evening Peak Hour In Option 2A, outbound peak-hour traffic travel time decreases by 1 minute compared to the No Build, whereas outbound transit travel times decrease by 8 minutes compared to the No Build. Overall network congestion decreases by 2% compared to the No Build. 3.6 Option 2B: S-curve Improvements with Outbound Bus Lane Addition and an Outbound Bus Bypass lane around the SH 82 Roundabout The following is an overview of how the S-curve improvements with an outbound bus lane feeding into a bus bypass lane from Cemetery Lane to west of the roundabout will operate in the peak hours in the year 2050. 3.6.1 Morning Peak Hour The addition of a bus bypass at Maroon Creek roundabout is not anticipated to impact morning peak-hour operations. Results from Option 1A are assumed to represent Option 2B since the geometry is the same 3.6.2 Evening Peak Hour The addition of a roundabout bypass decreases outbound peak-hour transit travel times by 3 minutes compared to Option 2A. Overall network congestion decreases by 7% compared to Option 2A. 3.7 Option 3: Phased PA The following is an overview of how the Phased Preferred Alternative (with bus transit) with a new signal at 7th Street and Main Street will operate in the 2050 peak hours. 3.7.1 Morning Peak Hour In Option 3, inbound peak-hour traffic operations remains relatively the same compared to the No Build. Transit travel times decrease by 2 minutes compared to the No Build. Overall network congestion decreases by 1% compared to the No Build. This indicates that the signal at Cemetery Lane and right turn from Hallam Street to 7th Street are not critical bottlenecks in the model, as removing them does not noticeably improve morning peak hour traffic conditions. 3.7.2 Evening Peak Hour In Option 3, outbound peak-hour traffic travel time decreases by 7 minutes. Transit travel times decrease by 8 minutes compared to the No Build. Overall network congestion increases by 7% compared to the No Build. This increase is primarily due to 80 Memorandum: Castle Creek Bridge Operational Traffic Analysis 14 the new traffic signal at the intersection of Main Street and 7th Street, which constrains outbound flow from Downtown Aspen. 3.8 Option 4: Splitshot The following is an overview of how the Splitshot (also known as the Couplet) with new signal at 7th Street and Main Street will operate in the 2050 peak hours. 3.8.1 Morning Peak Hour In Option 4, inbound peak-hour traffic travel time increases by about 24 minutes compared to the No Build scenario. Transit travel times increase by 13 minutes. This increase is primarily due to newly introduced U-turns (195 vehicles in the 2050 morning peak hour) at the Maroon Creek roundabout, which currently execute a southbound left turn from Cemetery Lane to inbound SH 82. These U-turns force the critical heavy inbound flow to yield (both lanes) at the roundabout. Overall network congestion increases by 57%, as indicated by the travel time increase. 3.8.2 Evening Peak Hour In Option 4, outbound peak-hour traffic travel time increases by 1 minute due to the U- turns mentioned previously (50 vehicles in the 2050 evening peak hour). Transit travel times decrease by 5 minutes compared to the No Build. Overall network congestion increases by 2% compared to the No Build. 3.9 Option 5: Down-valley Improvements This an overview of how select down-valley improvements will operate in the 2050 peak hours. These include modifications that are less costly than other options considering, such as Options 2, 3, and 4. Improvements modeled include:  Includes all features described in Option 1A (S-curve widening and associated intersection access)  Channelizes the outside lane of the westbound (outbound) movement at the Maroon Creek roundabout by adding a barrier between lanes – that is, continuos westbound lane through the roundabout  Removes 0.38 mile of the dedicated northbound (outbound) bus lane on SH 82 between Truscott Lane and Maroon Creek roundabout  Introduces 0.38 mile of the dedicated southbound (inbound) bus lane on SH 82 between the Airport Business Center and Service Center Road (alongside two southbound general traffic lanes)  Increases the maximum green time for the left turn from Brush Creek Road to outbound SH 82 from 15 seconds to 20 seconds 81 Memorandum: Castle Creek Bridge Operational Traffic Analysis 15 3.9.1 Morning Peak Hour In Option 5, inbound peak-hour traffic travel time remains relatively the same compared to the No Build, whereas transit travel times decrease by 2 minutes. Overall network congestion increases by 12% compared to the No Build. 3.9.2 Evening Peak Hour In Option 5, outbound peak-hour traffic travel time decreases by 5 minutes compared to the No Build, whereas transit travel times decrease by 6 minutes. Overall network congestion decreases by 43% compared to the No Build. This improvement is due to continuation of two general purpose travel lanes immediately north of the Truscott Place intersection, which increases the capacity of northbound flow through the Maroon Creek roundabout and thus improves throughput across Castle Creek Bridge. 3.10 Summary of Findings Based on the results discussed in the previous sections, each option was scored for its operational performance, as summarized in Table 1. A score of 3 indicates an option performs similarly overall to the No Build. A score of 1 to 2 means the option performs worse than the No Build, and a score higher than 3 means the option performs better. 82 Memorandum: Castle Creek Bridge Operational Traffic Analysis 16 Table 1: Options Scoring Table Criteria Weight Option 1A/B: S-curve Improvements Option 2A: S-curve Plus Outbound Transit Improvements Option 2B: 2A Plus Bus Bypass Option 3: Phased Preferred Alternative Option 4: Splitshot Option 5: Down-Valley Improvements Benefit to corridor travel times 25% 3 3 4 5 1 4 Benefit to overall network congestion 25% 2 2 3 3 1 5 Benefit to transit 50% 3.5 4 4.5 5 3.5 4 Overall score 100% 3.0 3.3 4.0 4.5 2.3 4.3 83 Memorandum: Castle Creek Bridge Operational Traffic Analysis 17 4. References Carly McGowan, City of Aspen. 2024. Personal communication (email) with Doug Stremel, Jacobs; and Pete Rice, City of Aspen. June 13. Colorado Department of Transportation (CDOT). n.d. Online Transportation Information System. Accessed July 2024. https://dtdapps.coloradodot.info/otis. Federal Highway Administration (FHWA). 1998. State Highway 82 Entrance to Aspen: Record of Decision. Project STA 082A-008. August. https://www.codot.gov/projects/ archived-project-sites/SH82/documents/1998ROD.pdf. Andi Staley, Traffic Operations Engineer, Colorado Department of Transportation (CDOT). 2024. Personal communication (email) with Carly McGowan, City of Aspen; Terri Partch, Jacobs; Tyler Pottorff, CDOT; and Zane Znamenacek, State of Colorado. June 18. StreetLight Data, Inc. (StreetLight). n.d. StreetLight metrics. Accessed July 2024. https://www.streetlightdata.com/. 84 State Highway 82 S-curve Technical Memorandum - Updated 1 Memorandum Subject: State Highway 82 S-curve Technical Memorandum - Updated Project Name: New Castle Creek Bridge Investigative Study with Revised Scope (the Project) Attention: City of Aspen (the City) From: Jacobs Date: July 2024 Copies to: Project File 1. Introduction This memorandum summarizes a concept analysis and safety evaluation performed by Jacobs regarding options for improving the S-curve alignment along State Highway (SH) 82 in Aspen, Colorado (Figure 1). The City requested Jacobs investigate design options and impacts of increasing the curve radii (curve softening) at two 90-degree (S--curve) turn locations entering and exiting Aspen. Two options were presented at an April 2024 Aspen City Council work session. Council directed further investigation into Option 2 with specific modifications. The Council made the following requests: provide access to SH 82 from North 8th Street and phase Option 2 to work in the interim two-lane existing bridge configuration and a future three-lane bridge configuration. Following the April work session, Jacobs was contracted to obtain topographic surveys in select areas, develop a traffic model, and progress the option to a 15% design level to refine and better understand right-of-way (ROW) impacts, traffic and operational impacts and costs for an initial and ultimate phase. The focus of the updated memorandum provides refined details for Option 2. For details on Option 1, refer to the SH 82 S-curve Technical Memo, April 2024 (Jacobs 2024A) 85 State Highway 82 S-curve Technical Memorandum - Updated 2 Figure 1: S-curve Alignment Study Area 2. History and Crash Data As a resort town and year-round destination for many travelers, traffic and congestion has continued to grow and challenge the existing infrastructure. Since the Entrance to Aspen Final Environmental Impact Statement (CDOT 1997) and Record of Decision (ROD) (FHWA 1998), many transportation and traffic studies have occurred over the years to evaluate SH 82 improvements through the city. Attachment 1 presents the transportation studies and implemented improvements specific to addressing issues on the S-curves and Castle Creek Bridge over the last 20 years. Not all studies were conclusive, resulting in non-implemented improvements. The safety and driver expectations of commuters in Aspen and along SH 82 is an important consideration when evaluating corridor modifications. According to the latest 5-year crash data (Colorado Department of Transportation, 2018 to 2022), most incidents were rear-end collisions occurring at the Castle Creek Bridge, on North 6th Street, and near or between the S-curve locations. Rear-end collisions are a indicator of congestion and speed differentials between vehicles. 86 State Highway 82 S-curve Technical Memorandum - Updated 3 As shown on Figure 2, crashes dipped during the COVID-19 pandemic; however, after COVID-19, crash statistics drastically increased and began to highlight an upward trend from 2018 (ignoring COVID-19 data). Figure 2: State Highway 82 Yearly Collision Count (Castle Creek Bridge to N. 6th St.) Several locations that experience more crashes, shown on Figure 3, have pinch points that contribute to these crashes. To address some of these crash problems and types (Figure 4), mitigation options could include minimizing conflict points by extending designated transit lanes, removing access at select intersecting streets, and reconfiguring the outbound zipper lane on West Main Street. The options discussed in the following section feature these enhancements to reduce conflict points while improving traffic flow. 0 5 10 15 20 25 2018 2019 2020 2021 2022 SH 82 Yearly Collision Count Disregarding COVID-19 years (2020 and 2021), crash data are trending upward 87 State Highway 82 S-curve Technical Memorandum - Updated 4 Figure 3: State Highway 82 Collision Classification (2018 to 2022) Figure 4: State Highway 82 Collision Location (2018 to 2022) Approach Turn, 4%Pedestrian/Bicycle, 6% Broadside, 10% Fixed Object, 19% Rear-End, 40% Sideswipe , 15% Unknown, 6% SH 82 Collision Classification Castle Creek Bridge 15% N 5th St 13% N 6th St 19%N 7th St 18% S 7th St 4% N 8th St 16% W Hallam St 7% Bleeker St 2% W Main St 6% SH 82 Collision Location 88 State Highway 82 S-curve Technical Memorandum - Updated 5 3. Option 2 Initial and Ultimate Phases Based on feedback from Aspen City Council and recommendations by Jacobs, improvements to the corridor could be implemented in two phases, initial and ultimate. The two-stepped approach will provide a phased solution for implementation, matching the existing two-lane bridge and widening for a future three-lane option. The initial phase buildout has been developed to smooth the S-curves while improving safety and outbound traffic flow, prioritizing buses, and maintaining bicycle and pedestrian connections. Access points were selectively eliminated to reduce conflict points on SH 82 and ease traffic congestion; however access from North 8th Street was added back into the design after the April 2024 work session. Further traffic impact analysis (that is, traffic modeling) was also performed to make quantitative assessments (such as travel time and delay) regarding the options’ travel benefits compared to a no-build option (refer to Section 4 for operations analysis). Softening the curves was strategic because layouts were based on accommodating buses in the outside lanes, heavy trucks (WB-67 design vehicle), and a future fixed-rail transit system. For the transit system, an assumption of a light rail transit (LRT) vehicle was selected to set a minimum radius for the curves (refer to Section 6, Transit Options). To accommodate the larger vehicles through the curves, lane width widening is provided in the S-curve corners. The initial phase is designed to work with the existing two-lane bridge; the ultimate phase is designed to widen the east side approach to accommodate a three-lane bridge, which would allow for two outbound lanes and one inbound lane across a new three-lane bridge over Castle Creek.1 The ultimate phase will extend the outbound bus lane to Cemetery Lane, where a widened intersection will provide a bus queue jump to prioritize transit (Figure 5). For the ultimate phase, the ingress access from North 8th Street is eliminated to avoid conflicts with the extended bus lane. Attachment 2 showcases the extents and impacts of the initial phase. Drawings depicting the ultimate phase are 1 As part of a separate task, Jacobs evaluated rehabilitating or replacing the existing SH 82 Castle Creek Bridge to accommodate two or three lanes. Figure 5: Illustration of Bus Queue Jump at Intersection 89 State Highway 82 S-curve Technical Memorandum - Updated 6 provided in Attachment 3, including the Cemetery Lane intersection reconfiguration with bus lane queue jump. These proposed improvements will have impacts, including ROW and temporary construction easement (TCE) acquisition, removal of existing trees, and minor impacts to a historic property. Following the April 2024 work session, Jacobs completed a site visit to collect additional field surveys to help verify and refine anticipated impacts in the S-curves. Additionally, the Project evaluated the drainage plan and determined some areas where drainage improvements were needed, which drove a need for additional temporary easements in the initial phase. In the ultimate phase, Jacobs noted the Cemetery Lane intersection widening for the bus queue jump lane. This widening would impact the Marolt Open Space (owned by the City). Because this is a sensitive area, special attention or construction of a wall may be needed to avoid or mitigate impacts to the property. Table 1 lists critical design elements included in both the initial and ultimate phases. Table 1: Option 2 Design Elements and Impacts, Initial and Ultimate Phase Design Elements and Impacts Initial Phase Ultimate Phase Two lanes of travel in each direction. Outer lanes designated bus and transit lanes. Yes Yes Matches three-lane bridge section. Outer outbound lane designated bus and transit lane. No Yes Matches two-lane bridge section. Yes No Ingress and egress to North 8th Street removed. No Yes Ingress to SH 82 from North 7th Street removed. Yes Yes Access from outbound SH 82 to North 7th Street. Yes Yes Increased radii at S-curves (accommodates large vehicles and future transit system). Yes Yes Ingress and egress to South 7th Street and West Main Street removed. Yes Yes Right-of-way and temporary construction easement acquisition [ROW/TCE] (square feet). 2,245/8,385 2,245/9,835 Mature trees impacted by option (quantity). 10 30 Historic property impacts (Not Adverse) on 7th and Main Street. Yes Yes 90 State Highway 82 S-curve Technical Memorandum - Updated 7 Design Elements and Impacts Initial Phase Ultimate Phase Queue jump at Cemetery Lane to facilitate merge of outbound buses with general traffic. No Yes Main Street zipper lane removed and converted to merge lane. Yes Yes Better facilitates outbound flow of traffic. No Yes Open space impacts. No Yes The Christian Science Society building at 734 West Main Street is the one historic property impacted by curve softening. Survey was performed on this property to better understand the impacts. Two large diameter trees and a smaller-diameter tree would be removed with the proposed improvements. ROW and TCEs are needed for softening the curve (encroachment on the property) and reconstructing the sidewalk across this property. Even with these impacts, the effect is expected to be Not Adverse for this historic property. Figures 6 and 7 provide examples of impacted trees in the curve-softening areas. Figures 6 and 7: Mature Trees Impacted by Curve Softening 4. Operational Benefits The following sections summarize quantitative and qualitative assessments of operations based on traffic modeling and engineering judgment. 4.1 Designated Bus Lanes A critical design element in the proposed options is the extension of designated bus lanes through the S-curves. It is generally understood that incorporating designated bus 91 State Highway 82 S-curve Technical Memorandum - Updated 8 lanes will help alleviate congestion and improve safety by removing zippering of bus and general traffic on SH 82. Currently, existing outbound buses merge with general traffic near North 6th Street and Main Street. The reintroduction of bus traffic to general traffic creates a bottleneck, causing friction between buses and general traffic. In the Option 2 initial phase, the outbound bus lane will be extended to the bus stop near 8th Street. After making it’s stop, the bus will then merge with SH 82 general traffic to cross the bridge over Castle Creek. The Option 2 ultimate phase will carry the outbound bus over a widened three-lane bridge and feature a bus queue jump for the transit lane at the Cemetery Lane signal, improving safety, reducing congestion, and prioritizing transit. Additionally, signal timing optimization at Cemetery Lane can be evaluated to improve traffic operations for all traffic. 4.2 S-curve Accesses To help with evening peak-period traffic flow, the City commissioned a prior project that removed access to SH 82 from West Hallam Street. Additionally, the City manually suspends access to SH 82 from North 7th Street during evening peak hours by placing a barricade to keep west end traffic from entering SH 82. Removing access points along SH 82 will improve traffic flow and reduce conflict points and potentially reduce traffic collisions. The Option 2 initial phase will maintain ingress at the 8th Street access to SH 82 and eliminate egress from SH 82 (Figure 8). This phase will also maintain egress from SH 82 to North 7th Street at Curve 1 but will eliminate ingress (Figure 9). However, the Option 2 ultimate phase will eliminate ingress from 8th Street access to SH 82. Figure 8: Access from North 8th Street The Option 2 initial and ultimate phases include a painted median at Curve 1, providing a smaller separation of opposing traffic (Figure 9). The Option 2 ultimate phase will eliminate ingress and egress access to SH 82 at Curve 2, cutting access from South 7th Street and West Main Street by connecting them (Figure 10). Eliminating access at this curve will reduce vehicle conflicts on SH 82 and improve traffic flow through the curve. 92 State Highway 82 S-curve Technical Memorandum - Updated 9 Figure 9: Curve 1 Option 2 Figure 10: Curve 2 Option 2 Pedestrian connectivity and safety are critical elements of each phase. Sidewalks and crosswalks are planned for each phase, and the existing inbound and outbound bus stops will remain in both phases. 4.3 Traffic Operations A Vissim traffic model was developed for the existing conditions, no-build scenario, and Option 2 initial and ultimate phases. The traffic model was run in the morning and evening peak hours for July 2024 traffic (existing conditions) and future (2050) traffic for no-build, initial and ultimate scenarios, which factors modest annual growth. The AM peak hour modeled was identified as 8:15 to 9:15 a.m. while the PM peak hour was identified as 4:30 to 5:30 p.m. The focus of the developed traffic model was the main routes and not west-end side streets. The initial phase S-curve improvements (without 8th St ingress) shows negligible time savings during the PM outbound peak hour for general traffic when compared to the no-build scenario (Figure 11). Adding the access in at 8th contributes to negligible delay for general traffic when compared to the no-build. The initial phase S-Curve improvements actually show slightly better transit times when compared to no-build and existing conditions. Option 2 Ultimate (3-Lane with bus priority queue jump at Cemetery Lane) does show time savings for both general and transit traffic over the no- build. In fact, transit spends five less minutes travelling to Brush Creek Rd while general traffic clocks in at nearly a minute less time. 93 State Highway 82 S-curve Technical Memorandum - Updated 10 Figure 11: Outbound PM Peak Hour Travel Time Comparisons From the traffic model, we can evaluate vehicle throughput for each scenario. Figure 12 details the travel throughput across the bridge in the outbound PM peak hour. Even though the ultimate adds an outbound transit lane across the bridge, transit would stay the same throughput and general traffic throughput is more than initial options but slightly less than if you didn’t build the three-lane bridge. This is likely due to the new westbound transit priority queue jump at Cemetery Lane. Figure 12: Outbound PM Peak Hour Throughput Comparisons 14:14 16:11 16:22 16:01 15:09 21:23 23:13 20:57 20:51 15:19 EXISTING 2050 NO BUILD 2050 OPTION 2 INITIAL (8TH ST ACCESS) 2050 OPTION 2 INITIAL (NO 8TH ST ACCESS) 2050 OPTION 2 ULTIMATE (NO 8TH ST ACCESS) SH 82 Outbound PM Peak Hour Travel Times (5th St to Brush Creek Rd) General Traffic Transit 896 780 755 735 771 EXISTING 2050 NO BUILD 2050 OPTION 2 INITIAL (8TH ST ACCESS) 2050 OPTION 2 INITIAL (NO 8TH ST ACCESS) 2050 OPTION 2 ULTIMATE (NO 8TH ST ACCESS) Outbound PM Peak Hour Througput across Bridge (Total Vehicles) 94 State Highway 82 S-curve Technical Memorandum - Updated 11 For the AM inbound peak hour, both the no-build and initial phase S-curve improvements show dramatic increases (roughly doubling) in travel times during the AM peak hour for general traffic when compared to the existing scenario (Figure 13). The initial phase S-Curve improvements and ultimate phase are no different geometrically than the no-build from Brush Creek to 8th Street. The jump in travel times is due to the heavy demand in the system in 2050. Note that this jump is not apparent in PM travel times because additional congestion towards the east of 5th Street is not captured in the travel time measurements, but any increase to PM travel demand would further congest downtown Aspen city streets in 2050. The S-Curve improvements do not alleviate AM inbound congestion. The inbound AM peak hour estimates travel times over one hour without plans to alleveiate the inbound demand. Longer travel times may force some commuters to choose transit, which would lessen the general traffic demand but additional transit service will be required to serve the shifted demand. Figure 13: Inbound AM Peak Hour Travel Time Comparisons Figure 14 details the travel throughput across the bridge in the inbound AM peak hour. For the ultimate, initial and no-build, there are no physical geometry changes affecting the throughput. The variance between no-build and initial is 57 vehicles, the slight dip between initial and ultimate is likely due to the transit priority queue jump at Cemetery Lane interrupting inbound flow and thereby lowering throughput. 32:29 1:07:54 1:07:43 1:03:52 16:39 24:07 23:28 24:16 EXISTING 2050 NO BUILD 2050 OPTION 2 INITIAL 2050 OPTION 2 ULTIMATE SH 82 Inbound AM Peak Hour Travel Times (Brush Creek Rd to 5th St) General Traffic Transit 95 State Highway 82 S-curve Technical Memorandum - Updated 12 Figure 14: Inbound AM Peak Hour Throughput Comparisons With the initial S-Curve improvements, general traffic flow and transit will not improve noticebaly over the no-build scenario. If the ultimate 3-lane solution was implemented, transit times would improve in the outbound direction during the PM peak hour, while the general traffic would see a slight travel time benefit (< 1 min.) alongside the dedicated transit lane. Neither phase of the S-Curve improvements benefit inbound transit or general traffic in the AM peak hour. 4.4 Castle Creek Bridge Widening Approaches to narrow bridges tend to slow and congest traffic because the traveler feels compressed by both oncoming traffic and the bridge elements along the driving lane. This will remain the case for any initial build that matches up with the existing two-lane bridge. Construction of a widened three-lane Castle Creek Bridge would be beneficial for traffic flow, safety, and emergency evacuation; however, the widening option has numerous challenges and impacts. Details are captured in the SH 82 Castle Creek Bridge Feasibility Study (Jacobs 2024B). Construction of a three-lane bridge would necessitate the widening of the approaches on both ends. Increasing capacity at the bridge is also critical when considering emergency egress. According to the City’s evacuation models, complete evacuation of the city will take more than 12 hours, even using both lanes of the existing bridge for outbound. Considering the initial phase of S-curve improvements, the existing two-lane bridge will remain a bottleneck and result in significant congestion during an evacuation event and daily peak periods. 966 1025 1082 1015 EXISTING 2050 NO BUILD 2050 OPTION 2 INITIAL (8TH ST ACCESS) 2050 OPTION 2 ULTIMATE (NO 8TH ST ACCESS) Inbound AM Peak Hour Throughput across Bridge (Total Vehicles) 96 State Highway 82 S-curve Technical Memorandum - Updated 13 Creating additional capacity and shoulder widths by widening the bridge and approaches at Castle Creek Bridge will improve safety, prioritize transit, and serve as an additional lane across the bridge for evacuation events. 5. State Highway 82 Pinch Point Analysis Pinch points can be defined as places where roads or paths become narrow or places of frequent traffic convergence, causing the traffic to slow down or stop. SH 82 has several pinch points that inhibit the flow of traffic, resulting in congestion or increase accident potential. S-curve modifications may alleviate some conflict points; however, congestion and queueing will remain if the pinch points are not properly addressed. The West End Neighborhood Traffic Study SH82 (Fox Tuttle 2022) peak-hour volume data indicate the S-curves, the Maroon Creek roundabout, and other traffic constrictions (pinch points) reduce capacity on SH 82 in the Castle Creek Bridge area to between 1,000 to 1,400 vehicles per hour. Figure 15 presents pinch point locations along the corridor. The six pinch points are as follows: 1) Maroon Creek roundabout 2) Existing Castle Creek Bridge 3) 90-degree S-curve (7th and Hallam Street) (Curve 1) 4) 90-degree S-curve (7th and Main Street) (Curve 2) 5) Outbound bus merge 6) Zipper lane Option 2 will soften the S-curves and remove access at conflicting streets, providing substantive improvements to Pinch Points 3 and 4. Additionally, Pinch Point 5 will be relocated but not resolved because buses will have to merge with general traffic at some other westerly point (depending on the phase). Pinch Point 6 is also being addressed to serve as an outside merge for outbound traffic rather than an atypical inside zipper lane, which will provide a safer merge but still cause traffic friction and congestion. 97 State Highway 82 S-curve Technical Memorandum - Updated 14 Figure 15: State Highway 82 Pinch Point Exhibit Note: Refer to Attachment 4 for an enlarged view. Although each phase provides improvements for the pinch points described, these improvements do not solve the bottleneck issues entirely. The Maroon Creek roundabout remains a pinch point, and Castle Creek Bridge will remain a point of restriction as a narrow two-lane bridge during the Option 2 initial phase. Jacobs is preparing a traffic study to evaluate other solutions to help with congestion and pinch points in the corridor. 6. Transit Options One consideration regarding adding designated bus lanes and softening the curves along the route now is that these bus lanes can be repurposed later for future transit options. Advancements in transit technology could provide more options than were available when the Entrance to Aspen ROD (FHWA 1998) was completed. These advancements include improvements to vehicle, route, and station designs, with an emphasis on efficiency, performance, and sustainability and reducing greenhouse gas emissions. Transit technology options include LRT, trolleybus, battery electric and fuel cell electric buses, and hybrid in-motion charging trolley buses. Technology selection will naturally be influenced by the subject corridor, including considerations of capacity, trip frequency, and snow. Given the common inclement weather in the Project corridor, issues such as snow removal, facility maintenance, mixed traffic management, and other 98 State Highway 82 S-curve Technical Memorandum - Updated 15 issues can be assessed through a technology comparison. Track systems and overhead lines can be adversely affected by snow and ice, and even high winds can disrupt the electrical line connections. The proposed curve-softening improvements will accommodate a variety of transit options and will not preclude a future fixed-rail LRT system when ridership and funding can support such an investment. There are numerous options regarding bus technology, with each providing its own pros and cons related to performance, infrastructure impacts, and operational and maintenance costs. If ridership warrants the consideration of longer articulated buses, these buses have a better turning radii than a typical bus, so the proposed improvements would be more than adequate to support these longer buses, as well. Attachment 5 documents some transit options for the corridor. 7. Option 2 Impacts and Costs Table 2 presents estimated costs of impacts from the curve softening based on 15% level design during Option 2: Initial Phase and Delta to Ultimate Phase. Impacts and cost have been refined based on 15% design and updated field surveys within the corridor. Each phase will result in property impacts, necessary for ROW acquisition, TCEs, and tree removals. ROW acquisition costs are based on recent acquisition data from City staff. Table 2: Summary of S-curve Initial and Delta Ultimate Impact Comparison S-curve Impact Initial Impact Quantity Δ Ultimate Impact Quantity Units Approximate Unit Cost (2024 dollars) Initial Impact Cost Δ Ultimate Impact Cost ROW Acquisition 2,245 + 0 Square feet $8,000 $17,960,000 + $0 TCE 8,385 +1,450 Square feet $1,500 $12,577,500 +$2,175,000 Tree Removals 10 +20 Each $10,000 $100,000 +$200,000 ROW unit costs remain estimated at $8,000 per square foot based on conversations with the City. Additionally, unit costs for TCEs remained the same at $1,500 per square foot. Actual costs of ROW and TCEs could be lower or higher than estimate. Tree removal quantity increased slightly for the initial construction because of additional survey findings. For the ultimate phase, construction tree removals increased when including the reconstructed Cemetery Lane intersection on the west side of the bridge, which was not included in the original assessment. 99 State Highway 82 S-curve Technical Memorandum - Updated 16 The 15% level design of the initial and ultimate phases allowed for the development of a conceptual cost estimate for each phase (Table 3). Table 3: Costs Summary for Initial and Ultimate Phase Implementation Scope of Work Initial Phase (Two Lane)[a] Ultimate Phase (Three Lane)[a] Δ Ultimate (Three Lane)[b] Construction Items $ 4,794,000 $ 8,371,000[c] $ 4,348,000[d] Utilities and Traffic Control $ 431,000 $ 1,005,000[c] $ 698,000[d] Design/NEPA/CE&I $ 1,927,000 $ 3,625,000[c] $ 2,064,000[d] ROW and TCEs $ 30,538,000 $ 32,713,000 $ 2,644,000 Project Totals $ 37,690,000 $ 45,714,000 $ 9,754,000 [a] 2024 dollars [b Inflated to 2028 dollars [c] Does not include a potential wall between SH 82 and the Marolt property [d] Costs for design and reconstruction of the approaches for a Three-lane Shifted bridge were provided for in the cost estimates developed for the Castle Creek Bridge Feasibility Study (Jacobs 2024B). NEPA = National Environmental Policy Act CE&I = Construction Engineering and Indirect costs After the initial phase construction an additional $8 million is needed to widen for the three-lane bridge option on both approaches to the bridge, which would also include the bus lane priority queue jump at Cemetery Lane. Inflating to 4 years in the future (2028) at 5% interest increases costs to $9.7 million. These costs do not include construction of a three-lane bridge. 8. Conclusions Constructing the Option 2 initial phase discussed in this memorandum would reduce conflict points, which increases safety and extends the bus lanes, prioritizing transit within the S-curves. With the traffic modeling factored there are negligible gains to general traffic flow compared to the no-build. And, this initial phase does not adequately address the larger congestion, travel time problems, and emergency egress for the City. Implementation of the ultimate phase improvements (3-Lane) would improve outbound general traffic flow and prioritize transit but does little to help inbound traffic nor does this phase adequately address the other nearby corridor pinch points outside of the S-curves. Overall Project costs for design, construction, and impact costs are quite high for either phase of improvements. For the initial phase, matching the existing two-lane bridge, construction, utilities, traffic control, design, and ROW is 100 State Highway 82 S-curve Technical Memorandum - Updated 17 estimated at $37.7 million in 2024 dollars. Though these estimates provide refined perspective of estimated cost and impacts against benefits to safety and mobility, they are based only on a 15% design effort. 9. References Colorado Department of Transportation (CDOT). 1997. State Highway 82 Entrance to Aspen: Final Environmental Impact Statement, Section 4(f), Volume I. Project STA 082A008. August.  Federal Highway Administration (FHWA). 1998. State Highway 82 Entrance to Aspen: Record of Decision. Project STA 082A-008. August. https://www.codot.gov/projects/ archived-project-sites/SH82/documents/1998ROD.pdf. Jacobs. 2024A. SH 82 S-Curve Technical Memo. Jacobs. 2024B. SH 82 Over Castle Creek Bridge Feasibility Study. Fox Tuttle Transportation Group (Fox Tuttle). 2022. City of Aspen West End Neighborhood Traffic Study SH82. 101 State Highway 82 S-curve Technical Memorandum - Updated Attachment 1: History of Studies and Implemented Improvements Related to S-curves 102 103 S Curve and CCB Improvements for trac flow and pedestrian safety (2002-2024)City of Aspen N 8TH STN 7TH STN 6TH STW HALL A M S T W MAIN S TCEMETERY LNW BLEE K E R S T Source: Esri Community Maps Contributors, City of Aspen GIS, Pitkin County, © OpenStreetMap, Microsoft, Esri, TomTom, Garmin, SafeGraph, GeoTechnologies, Inc, METI/NASA, USGS, Bureau of Land Management, EPA, NPS, US Census Bureau, USDA, USFWS | Maxar, Microsoft Traffic flow: Improved intersection configuration. Traffic flow: Island modifications made Traffic flow: Turn restrictions implemented Pedestrian Safety: Crosswalk implemented. Pedestrian Safety: Bridge sidewalk widened from 5' to 8'. Concrete and steel barrier added.Transit Capacity: Main Street PM Peak transit lane added Legend Castle Creek Bridge Connectivity Study S Curves Citizen Task Force Study Traffic flow: Access closures implemented. 104 State Highway 82 S-curve Technical Memorandum - Updated Attachment 2: S-curves Option 2 – Initial Phase 105 Option 2 Initial | Sheet 1City of Aspen LEGEND Trees Impacted Access to SH 82 RemovedACCESS REMOVED Dedicated Bus Lane Sidewalk General Traffic Lane Remove Zipper Lane Raised Median Historical Property Impacted 0' 50' 100'200' W BLEEKER STN 8TH STN 7TH STMATCHLINE SHEET 2 W HALLAM ST RIGHT TURN ONLY B B ACCESS REMOVED ACCESS REMOVED SH 82 A A 12'12' SH 82 GENERAL TRAFFIC SECTION A-A GENERAL TRAFFIC 12' –16'12'12'12'12' GENERAL TRAFFICDEDICATEDBUS LANE GENERAL TRAFFIC DEDICATEDBUS LANESTRIPED MEDIAN 12'12'12' –16'12' –16' SH 82 SECTION B-B VARIES 106 Option 2 Initial | Sheet 2City of Aspen LEGEND Trees Impacted Access to SH 82 RemovedACCESS REMOVED Dedicated Bus Lane Sidewalk General Traffic Lane Remove Zipper Lane Historical Property Impacted 0' 50' 100'200'N 6TH STN 5TH STS 6TH STS 7TH STW MAIN ST SECTION D-D SH 82 12'12'12'12'12'11' SECTION C-C SH 82 12'12'12'12' GENERAL TRAFFICDEDICATEDBUS LANE DEDICATEDBUS LANEGENERAL TRAFFIC ACCESS REMOVED MATCHLINE SHEET 1 D D C C GENERAL TRAFFICDEDICATEDBUS LANE DEDICATEDBUS LANEGENERAL TRAFFIC GENERAL TRAFFIC GENERAL TRAFFICDEDICATEDBUS LANEPARKING LEFT TURN ONLY DEDICATEDBUS LANE 107 State Highway 82 S-curve Technical Memorandum - Updated Attachment 3: S-curves Option 2 – Ultimate Phase 108 Option 2 Ultimate | Sheet 1City of Aspen LEGEND Trees Impacted Access to SH 82 RemovedACCESS REMOVED Dedicated Bus Lane Sidewalk General Traffic Lane Remove Zipper Lane Raised Median Historical Property Impacted 0' 50' 100 200'Cemetery Ln .MATCHLINE SHEET 2SH 82 109 Option 2 Ultimate | Sheet 2City of Aspen LEGEND Trees Impacted Access to SH 82 RemovedACCESS REMOVED Dedicated Bus Lane Sidewalk General Traffic Lane Remove Zipper Lane Raised Median Historical Property Impacted 0'50'100'200' W BLEEKER STN 8TH STN 7TH STMATCHLINE SHEET 2 W HALLAM ST B B ACCESS REMOVED ACCESS REMOVED SH 82 A A 12'12'12' SH 82 GENERAL TRAFFIC SECTION A-A DEDICATEDBUS LANE GENERAL TRAFFIC 12' –16'12'12'12'12' GENERAL TRAFFICDEDICATEDBUS LANE GENERAL TRAFFIC DEDICATEDBUS LANESTRIPED MEDIAN 12'12'12' –16'12' –16' SH 82 SECTION B-B VARIES 110 Option 2 Ultimate | Sheet 3City of Aspen LEGEND Trees Impacted Access to SH 82 RemovedACCESS REMOVED Dedicated Bus Lane Sidewalk General Traffic Lane Remove Zipper Lane Historical Property Impacted 0' 50' 100'200'N 6TH STN 5TH STS 6TH STS 7TH STW MAIN ST SECTION D-D SH 82 12'12'12'12'12'11' SECTION C-C SH 82 12'12'12'12' GENERAL TRAFFICDEDICATEDBUS LANE DEDICATEDBUS LANEGENERAL TRAFFIC ACCESS REMOVED MATCHLINE SHEET 1 D D C C GENERAL TRAFFICDEDICATEDBUS LANE DEDICATEDBUS LANEGENERAL TRAFFIC GENERAL TRAFFIC GENERAL TRAFFICDEDICATEDBUS LANEPARKING LEFT TURN ONLY DEDICATEDBUS LANE 111 State Highway 82 S-curve Technical Memorandum - Updated Attachment 4: Pinch Point Diagram 112 SH 82 Pinch Point ExhibitCity of AspenEnd S-Curve Alternative AnalysisPINCH4PINCH2PINCH1PINCH6PINCH5HPINCH3PINCH 6:Zipper lane merges from 2 lanes to 1 for outbound travellers.MAROON CREEK RDMAROON CRK RDPINCH 5:Designated peak period bus lane ends. Busses merge with local traffic (single lane).Start S-Curve Alternative AnalysisPINCH 3 & 4:90-degree S-Curves with intersecting streets impedes traffic flow and introduces conflict points.PINCH 2:Narrow, 2-lane bridge, constricts the flow of traffic, reducing traveler speed, resulting in queuing and rear-end collisions.PINCH 1: Maroon Creek Roundabout perpetuates movement of traffic, but high traffic volume constricts flow and results in congestion.W MAIN STW BLEEKER STN 6TH STN 7TH STN 5TH STW HALLAM STCEMETERY LNN 8TH STSource: Esri Community Maps Contributors, City of Aspen GIS, Pitkin County, © OpenStreetMap, Microsoft, Esri, TomTom, Garmin, SafeGraph, GeoTechnologies, Inc, METI/NASA, USGS, Bureau of Land Management, EPA, NPS, US Census Bureau, USDA, USFWS | Maxar, Microsoft113 State Highway 82 S-curve Technical Memorandum - Updated Attachment 5: Transit Options 114 Public Transit Options Aspen, CO 115 ©Jacobs 2024 Light Rail Reduces air pollution and greenhouse gas emissions by providing alternative to private vehicles Higher passenger capacity per lane per hour Lower operating cost per passenger Can be accommodated through S-Curve alignment High construction costs No intermingling of transit and general traffic Overhead electric can be affected by high winds and snow 116 ©Jacobs 2024 Trolleybus 3 Draws power from overhead wires and requires poles Differs from a traditional trolley system in that two wires and two poles are necessary to complete the electrical circuit Bus has greater flexibility to maneuver along the roadway Trackless design that provides more opportunities to mix traffic and maximize use of ROW Track systems and overhead lines can be adversely affected by snow and ice High winds can disrupt the bus/electric line connection 117 ©Jacobs 2024 Battery Electric Bus 4 Battery electric buses and fuel cell electric buses eliminate the need and impacts from electrification lines Accommodates sensitive built environments and constrained ROW Battery life and recharge time can pose a challenge Recharged, stationary, in 5–20-minute sessions 118 ©Jacobs 2024 Overhead In-Motion Charging Trolleybus 5 In-motion charging allows operations to continue smoothly without interruption In-motion charging trolleybuses use overhead catenary wires, covering about 20-40% of the route, otherwise battery powered Reduces overall impacts caused by catenary wires Reduces challenges associated with recharging systems Ideal in rural/urban corridors 119 ©Jacobs 2024 Trackless Tram 6 A hybrid technology utilizing rubber wheels and powered by rechargeable batteries Sustainable public transit with net zero emission vehicle Guided by digital rail with sensors in road, no catenary wires required Optical guidance may not be ideal in heavy snow conditions Vehicle weight requires substantial roadway surfaces 120 1 Memorandum Subject: Analysis of Sidewalk Removal from the Castle Creek Bridge Project Name: New Castle Creek Bridge Investigative Study with Revised Scope (the Project) Attention: City of Aspen (the City); Pete Rice and Carly McGowan From: Jacobs Date: July 26, 2024 Copies to: Doug Stremel, Jim Clarke, and Beth Tosti 1. Introduction A three-lane bridge replacement with a sidewalk was previously assessed in the final State Highway (SH) 82 Over Castle Creek Bridge Feasibility Study (Feasibility Study), with a total bridge width of 52 feet for a sidewalk, three lanes of traffic, and associated shoulders. Aspen City Council requested further investigation and comparison of two options:  Three-lane Shifted: Provided two lanes of traffic during all construction phases  Three-lane Faster: Eliminated 1 year of construction time The current SH 82 bridge over Castle Creek has two sidewalks, one of which was widened in 2018. The north sidewalk is protected behind a barrier and is 8 feet wide. The south sidewalk on the bridge is unprotected and is 5 feet wide. As part of the Project, the City currently is analyzing replacing the existing two-lane bridge with a three-lane bridge in the same approximate SH 82 alignment. This memorandum (memo) analyzes the potential removal of sidewalks from a new three-lane bridge 1 to reduce right-of-way (ROW) impacts and Project costs. Analysis of bridge phasing and associated impacts are based on available Geographic Information System (GIS) data, aerial photography, elevations, and roadway shape files. The feasibility of sidewalk removal considered these aspects:  Federal, state, and local policy, including Americans with Disabilities Act (ADA) requirements  Volumes of pedestrian and bicycle users  Potential alternative bicycle and pedestrian routes, considering increases in travel time and distance 1 This memo does not address sidewalk removal from a rehabilitated bridge, a new two-lane bridge, or the Three-lane Centered options. 121 Analysis of Sidewalk Removal from the Castle Creek Bridge 2  Impacts to school campus usage or Safe Routes to Schools (SRTS)  Construction impacts of sidewalk removal for a three-lane bridge replacement, including the following: - Construction phasing for a three-lane bridge (three 11-foot lanes and two 3-foot shoulders) with one lane in each direction during all phases of construction - Comparison to the previously assessed Three-lane Shifted and Three-lane Faster options, reviewing ROW impacts - Bridge construction schedule and cost  Private property and utility impacts with and without a sidewalk 2. Federal, State, and Local Policy Implications Federal, state, and local laws, regulations, and policies were considered when assessing sidewalk removal. Federal and state policies both state that existing pedestrian facilities cannot be severed or removed unless a reasonable alternative route is provided (reasonableness can consider cost, but this judgement is subjective and usually considered to be more than 20% of the overall Project cost). Further, City engineering standards require a sidewalk in this area. The ADA requires any new facility constructed by a government entity to meet ADA design criteria, regardless of the funding source. Based on these regulations, codes, and policies, it would be difficult to not include sidewalks on a future bridge, even if local funding were used for the Project. The following sections provide additional details about relevant federal, state, and local requirements. 2.1 Americans with Disabilities Act Requirements Colorado Department of Transportation (CDOT) confirmed that any new construction in the public ROW would need to meet the ADA requirements and design criteria, specifically the Public Right-of-Way Accessibility Guidelines (PROWAG). These guidelines require a minimum 48-inch-wide sidewalk or path with a grade no greater than 5% and a cross slope no greater than 2.1%. 2.2 Other Federal Statutes Federal requirements would apply to a future bridge replacement project if federal transportation funds are used. These requirements also would apply if the bridge is replaced as part of implementing a phase of the Preferred Alternative from the Entrance to Aspen Environmental Impact Statement (CDOT 1997) or if a new National Environmental Policy Act (NEPA) process were initiated. 122 Analysis of Sidewalk Removal from the Castle Creek Bridge 3 The federal government can withhold approval of projects that would negatively impact pedestrians and bicycles. Relevant federal code and regulatory citations follow:  23 Code of Federal Regulations (CFR) 652 provides “procedures relating to the provision of pedestrian and bicycle accommodations on Federal-aid projects, and Federal participation in the cost of these accommodations and projects.”  23 United States Code (USC) 109(m) relates to the severance of existing bike and pedestrian routes. No federal funding will be approved for a project that reduces pedestrian safety unless a reasonable alternative route can be provided. Specific language states that “[t]he Secretary shall not approve any project or take any regulatory action under this title that will result in the severance of an existing major route or have significant adverse impact on the safety for non-motorized transportation traffic and light motorcycles, unless such project or regulatory action provides for a reasonable alternate route, or such a route exists.”  23 USC 217(e) specifically relates to federal funding for replaced or rehbilitated bridges, stating that safe accommodations must be provided as long as the cost is reasonable. Specific language states that “[i]n the case where a highway bridge deck being replaced or rehabilitated with Federal financial participation is located on a highway on which bicycles are permitted to operate at each end of such bridge, and the Secretary determines that the safe accommodation of bicycles can be provided at a reasonable cost as a part of such replacement or rehabilitation, then such bridge shall be so replaced or rehabilitated as to provide such safe accommodations.” Although this statutory requirement only mentions bicycles, the U.S. Department of Transportation encourages states and local governments to apply this same policy to pedestrian facilities. 2.3 State Statute State statute indicates that pedestrian and bicycle facilities must be constructed to provide safe access for all users. Colorado Revised Statutes 43-1-120 states the following:  “It is in the best interest of all Coloradans to promote transportation mode choice by enhancing safety and mobility for bicyclists and pedestrians on or along the state highway system.”  “The department (of Transportation) has adopted a bike and pedestrian policy directive to further this goal.” 123 Analysis of Sidewalk Removal from the Castle Creek Bridge 4  “It is necessary and appropriate to elevate the status of the bike and pedestrian policy of the department to that of law by codifying it in subsection (2) of this section… - The department and its subdivisions shall provide transportation infrastructure that accommodates bicycle and pedestrian use of public streets in a manner that is safe and reliable for all users of public streets. - The needs of bicyclists and pedestrians shall be included in the planning, design, and operation of transportation facilities as a matter of routine. - Any decision of the department to not accommodate the needs of bicyclists and pedestrians shall be documented based on exemption criteria that were established by the commission before the decision was made.” 2.4 City of Aspen Policy The City’s Engineering Standards (City 2019) also require a sidewalk in any area that is not indicated in the adopted maps as a “Sidewalk Deferred Zone.” The existing bridge is not in a Sidewalk Deferred Zone. 2.5 Colorado Department of Transportation and Federal Highway Administration Coordination In a letter to CDOT dated May 7, 2024, regarding the Project, the City asked for clarification and confirmation on several aspects of the Project (City, pers. comm. 2024). In its response, CDOT (with Federal Highway Administration Coordination review and concurrence) confirmed the following (CDOT, pers. comm. 2024):  The Castle Creek Bridge sidewalk must be replaced on a new or rehabilitated bridge if federal and/or state funding is used and a reasonable alternative route is not identified.  If the City opts to self-fund, the sidewalk must be replaced on the new or rehabilitated Castle Creek Bridge if the route remains a state highway.  Any new trail or path would need to meet the ADA design criteria. CDOT bike and pedestrian coordinators for the state and for the region commented in an email that any alternative route would need to meet current ADA policy (PROWAG) and that it was unlikely that an alternative route would be determined to be reasonable unless it provided a comparable distance and grade (Ipsen and Van Vonno, pers. comm. 2024). 124 Analysis of Sidewalk Removal from the Castle Creek Bridge 5 3. Existing Sidewalk History and Usage The existing sidewalks’ history and usage were reviewed to determine why they were constructed and to gauge if the sidewalks provide an important multimodal connection or if this facility is underused. 3.1 Sidewalk History City staff provided a City Council memo from 2016 to inform the history of the sidewalk connection. The memo states that the Castle Creek Bridge and the Hallam corridor were identified as a deficient link in 2013 by the City’s Open Space and Trails Board and other City departments. The City’s Trail System Manager confirmed that the sidewalks at the time were narrow and unprotected from traffic. The trail was also recognized as a critical link for pedestrians and cyclists to access the north side of the city. In 2014, a conceptual plan was developed to address the deficiency. In April 2016, a Living Lab experiment was conducted on the bridge to study its usage. A Living Lab is a temporary setup of a potential roadway, path, or signage change using cones or striping to model how traffic or pedestrians respond to a changed condition. Living Lab results indicated that cyclists split at Castle Creek Bridge between going toward the Marolt pedestrian bridge and continuing onto Hallam Street. The Living Lab also showed that the peak-hour usage on the bridge doubled for pedestrians and increased by 47% for bicycles. Overall, 28,337 pedestrians used the facility during the 3-month Living Lab trial. Based on the community response to the Living Lab and community surveys about the need for this connection, the widened sidewalk and barrier were constructed in 2018. The 2023 Aspen Trail Map (Figure 1) identifies the bridge sidewalks as a major east-west connection and part of the Hallam Bicycle and Pedestrian Route. 125 Analysis of Sidewalk Removal from the Castle Creek Bridge 6 Figure 1: 2023 Aspen Trail Map Source: City, 2023. 3.2 Aspen School Campus Usage and Safe Routes to Schools Designation SRTS is a national program dedicated to improving the safety of students moving to and from school. The program provides strategies, resources, and funding to improve student safety. The Aspen School District Transportation Director confirmed that the Castle Creek Bridge is a designated SRTS route. The director also stated that approximately 230 students live within northwest Aspen and are likely to use the sidewalk on the bridge. Of those 230 students, 120 would be primarily using the bridge based on their age and ability to ride a bike, scooter, or skateboard instead of taking the bus or driving with their parents (Mahaffey, pers. comm. 2024). Having a route that local parents consider safe for their kids can reduce vehicular traffic to and from school, as parents are more likely to allow their kids to ride their bikes, scooter, or walk. For example, in the City of Glenwood Springs, a small, separated section of sidewalk across a new pedestrian bridge at the corner of Midland and Mount Sopris Avenue, increased the safety and volume of children walking from the adjacent neighborhood to Sopris Elementary. Children no longer need to step onto the road shoulder on their route to school. One could reasonably assume that the SH 82 congestion near the bridge adds incentive for parents to have their kids use other modes to travel to and from school. Removing the sidewalks on the bridge would likely lead to increasing vehicular traffic in the school peak drop-off and pickup hours. 126 Analysis of Sidewalk Removal from the Castle Creek Bridge 7 3.3 Volume of Bicycle Usage Different data sources were used to assess bike and pedestrian usage. City Engineering and Trails staff took bicycle counts using tube counters between 2015 and 2022 at two locations: (1) on the bridge and (2) at the North 6th and Hallam Street intersection, located approximately two blocks from the eastern bridge approach. The bicycle counts are summarized as follows:  6th and Hallam (June 2015): - Daily average: 233 - Busiest day: 382  6th and Hallam (2017 through 2023 [except for 2018, when construction occurred]): - No average numbers available - Busiest days: Approximately 360 to 375  Castle Creek Bridge (May 1 to August 31, 2016): - Daily average: 248 - Busiest day: 740 Location-based service (LBS) cellular phone data also were used to assess bicycle usage on the Castle Creek Bridge. These data are summarized as follows:  Daily average number of bikes in 2019: 700  Daily average number of bikes in 2020: 740  Daily average number of bikes in 2021: 560 The tube counts at 6th and Hallam varied significantly from the LBS cellular phone data averages on the bridge. This variability could indicate that many people cross the bridge and turn north or south on a different route before reaching 6th and Hallam. The LBS data also show a significant drop in 2021, likely because of the COVID-19 pandemic. City staff believe that current volumes are more closely represented by the 2019 and 2020 numbers. 3.4 Comparison of Bicycle Usage on the Marolt Trail Bridge City Engineering and Trails also took bicycle counts on the Marolt Trail Bridge during the same time frames. The counts, summarized as follows, appear to indicate that both facilities are well used by different groups of users:  June 2015: - Daily average: 591 - Busiest day: 1,027 127 Analysis of Sidewalk Removal from the Castle Creek Bridge 8  May through August 2016: - Daily average: 221 (including a counter malfunction) - Busiest day: 962.  2017 through 2023 (except for 2018, when construction occurred): - Daily average: 332 - Busiest day: 1,782. 4. Alternative Routes As noted in Section 2, the feasibility of not including sidewalks on a new Castle Creek Bridge depends on whether a reasonable alternative route exists or could be provided. No set standard exists for determining whether an alternative route is deemed reasonable. CDOT Bicycle and Pedestrian Coordinators have both said that distance, grade, and existence of another facility (a sidewalk for pedestrians, instead of a roadway shoulder) were important considerations. Also, both have confirmed that the ADA regulations (PROWAG) would apply to any newly constructed facility. The extent to which a new route is considered out of direction compared to the existing bridge sidewalks depends on origins and destinations for bicycle and pedestrian trips, which can vary widely. Therefore, making comparisons required assuming common origins and destinations for these trips. These analyses assume a common western origin at the location of the existing bridge sidewalk and the Marolt Trail connection. To the east, two locations were used: (1) one based on access to the second most highly used bus stop in the system at 8th and Hallam and (2) one based on access to 7th and Main (downtown). The comparison analyzed three alternative routes to each destination (Figures 2 and 3; Tables 1 and 2). The Power Plant Road route, marked by blue dashes on Figures 2 and 3, would require substantial construction to build an ADA accessible path, including path switchbacks, wheelchair rest areas, and retaining walls for support. The Marolt Trail route, shown in green, is a well-used pedestrian route crossing on a bridge over Castle Creek to the south. Travel time on each route was based on a traffic engineering design criteria for pedestrian walking speed of 3 miles per hour, or 0.0501 mile per minute. Bicycle trip times were not included because of their variability. 128 Analysis of Sidewalk Removal from the Castle Creek Bridge 9 Figure 2: Castle Creek Bridge West to 8th and Hallam Street Bus Stop Table 1: Bike and Pedestrian Route Comparison from Castle Creek Bridge East to 8th and Hallam Street Bus Stop Route Distance Pedestrian Walking Time Castle Creek Bridge to 8th and Hallam (yellow line with “x” symbols) 0.19 mile 3.8 minutes Castle Creek Bridge via Marolt to 8th and Hallam (green dots) 0.63 mile 12.6 minutes Castle Creek Bridge via Power Plant Road to 8th and Hallam (blue dashes) 0.60 mile 12.0 minutes 129 Analysis of Sidewalk Removal from the Castle Creek Bridge 10 Figure 3: Analysis of Routes into Downtown (7th and Main) Table 2: Bike and Pedestrian Route Comparison from Castle Creek Bridge East to 7th and Main: Downtown Analysis Route: Downtown Analysis Distance Pedestrian Walking Time Castle Creek Bridge to 7th and Main (yellow line with “x” symbols) 0.34 mile 6.8 minutes Castle Creek Bridge to 7th and Main via Marolt (green dots) 0.48 mile 9.6 minutes Castle Creek Bridge to 7th and Main via Power Plant (blue dashes) 0.76 mile 15.2 minutes Constructing a separate pedestrian bridge adjacent to the Three-lane Shifted bridge reconstruction is also feasible. The primary benefits of an adjacent separated structure are that the structure would allow pedestrians to remain on nearly the same alignment and grade as the existing sidewalks. The structure would better protect pedestrians from vehicular traffic and allow utilities to be relocated from the main bridge during construction, simplifying the construction. However, adding a pedestrian bridge would be unlikely to reduce overall costs. 130 Analysis of Sidewalk Removal from the Castle Creek Bridge 11 5. Sidewalk Removal Impacts on the Bridge Options When removing the sidewalk in the final configuration, the final bridge section would accommodate three 11-foot lanes and two 3-foot shoulders for a total out-to-out width of 42 feet, as compared to the 52-foot-wide options previously assessed in the Feasibility Study. Options that provide access for one lane in each direction (two-way traffic) during all construction phases were given priority. Pedestrian access during construction was eliminated if beneficial to the bridge construction. The benefits and challenges related to sidewalk removal on the ROW and bridge cost are summarized in the following sections for each option as compared to the same options with a sidewalk. 5.1.1 Three-lane Shifted: No Sidewalk The Three-lane Shifted option was reassessed by removing the existing sidewalks in the final configuration; however, no significant benefits were observed. The existing sidewalk area cannot be used for vehicular traffic because the outside girder was designed for only pedestrian loading, which results in the same first phase of construction as previously presented for the Three-lane Shifted option. Refer to Figure 4 for the bridge footprint. Benefits and challenges of this option are summarized as follows:  Benefits: - Provides two temporary lanes during all construction phases - Results in narrower bridge width, which reduces overall bridge cost  Challenges: - Maintains over 4 feet of ROW acquisition on the south side - Modifies the existing north sidewalk, removing the 3-foot sidewalk constructed in 2018 - Retains a 4-year construction duration 131 Analysis of Sidewalk Removal from the Castle Creek Bridge 12 Figure 4: Three-lane Shifted: No Sidewalk, Bridge Footprint 5.1.2 Three-lane Faster: No Sidewalk Reassessment of the Three-lane Faster option with the sidewalks removed in the final configuration also provided no significant benefit. The main benefit of the original Three-lane Faster option was that it eliminated a construction phase by overbuilding the bridge width on both sides of the existing bridge, but it allowed only one lane of traffic on the existing bridge during the first phase of construction. Without a sidewalk, the first phase of construction would still use a single lane of traffic as previously presented, which requires a companion detour for the opposing traffic direction. The total bridge width constructed would not change, as the required width is controlled by the second phase of construction, when two temporary lanes will be provided. Removing the sidewalk would only provide more room for vehicular access in the final configuration, further overbuilding the bridge beyond the width needed for only the traffic lanes and shoulders. The construction schedule would remain 3 years. 5.1.3 Other Option Considerations Without the need for a sidewalk, other options that could accommodate two lanes during all phases of construction were briefly considered. Only one additional option, Three-lane North (Figure 5), could accommodate two lanes during construction. Shifting the bridge to the north was initially not considered feasible because of the ROW impacts. The Three-lane North option was reassessed by removing the existing sidewalks in the final configuration; however, no significant benefits were observed. The new bridge location is still controlled by the first phase of construction to accommodate two lanes on the existing bridge. This option would require over 6 feet of ROW acquisition on the north side, resulting in a much larger acquisition area than the Three Lane Shifted (south) option. Beginning construction on the north side also requires all utilities to be relocated twice, increasing the cost and field time for utility work. 132 Analysis of Sidewalk Removal from the Castle Creek Bridge 13 In summary, no traditional phased construction options accommodate two lanes of traffic on the existing alignment during all phases of construction without having ROW impacts. The Feasibility Study outlined one option that did not have ROW impacts, Three-lane Centered, which only accommodates one lane of traffic on the existing alignment in most construction phases. Figure 5: Three-lane North: No Sidewalk, Bridge Footprint 5.2 Separate Pedestrian Bridge Construction of an adjacent pedestrian bridge that supports utilities was considered. This concept is feasible and most advantageous combined with the Three-lane Shifted option, which does not extend beyond the north side of the existing bridge. This scenario allows the pedestrian bridge to be constructed first. The pedestrian bridge can also support the relocated utilities. Typically, a pedestrian bridge for this purpose is a prefabricated steel truss bridge. Benefits and challenges of constructing an adjacent pedestrian bridge are summarized as follows:  Benefits: - Allows pedestrian access during all construction phases and permanently afterward. Section 4, Alternative Routes, provides additional information - Provides a support system for the relocated utilities, which can occur before the vehicular bridge construction starts  Challenges: - Requires over 7 feet of ROW acquisition for a long stretch in the northeast corner - Requires reconstruction of each pedestrian access (sidewalk) for the residences at 926 to 930 West Hallam Street 133 Analysis of Sidewalk Removal from the Castle Creek Bridge 14 - Introduces another bridge asset to maintain, with ownership to be determined between the City and CDOT - Likely shuts down Power Plant Road for bridge erection if a prefabricated bridge type is used - Requires retaining wall systems at both ends to adjust the grading for the new pedestrian bridge The final configuration of a pedestrian bridge adjacent to the vehicular bridge would have a significant gap between the two bridges to accommodate construction phasing. The two bridges would be over 15 feet apart from one another. Figure 6 shows the approximate pedestrian bridge layout and inherent gap between bridges. Figure 6: Pedestrian Bridge Footprint Adjacent to New Three-lane Bridge The total site impacts to build a pedestrian bridge include the following:  Almost 800 square feet (ft2) of ROW acquisition, costing approximately $6,300,000 2  Additional 10-foot offset for a temporary construction easement (TCE), totaling $1,900,000 3  Approximately $2,500,000 in pedestrian bridge construction costs (does not include site construction cost)  Closures on Power Plant Road for bridge erection 5.3 Comparison Summary Between Bridge Options The three-lane bridge options with sidewalks previously analyzed in the Feasibility Study were compared to the similar alternatives without sidewalks. Table 3 summarizes the 2 Assumes $8,000 per ft2 of ROW acquisition, the same rate used in the Feasibility Study for accurate comparison. 3 Assumes $1,500 per ft2 of TCE, the same rate used in the Feasibility Study for accurate comparison. 134 Analysis of Sidewalk Removal from the Castle Creek Bridge 15 comparison of the two sets of options, comparing ROW impacts, utility impacts, bridge cost, and construction duration. 135 Analysis of Sidewalk Removal from the Castle Creek Bridge 16 Table 3: Comparison of Bridge Options With and Without a Sidewalk Sidewalk Status Bridge Options ROW Impacts Utility Impacts Two Lanes Open During Construction Bridge Cost Only[a] Construction Duration[b] Pedestrian Bridge Feasibility Bridge with sidewalks Three-lane Shifted 673 ft2 1 relocation period required On existing alignment $10,000,000 (22,048 ft2 of bridge area) 4 years Not applicable Bridge with sidewalks Three-lane Faster 574 ft2 1 relocation period required, or temporary support during construction With temporary Marolt detour $11,100,000 (24,557 ft2 of bridge area) 3 years Not applicable Bridge without sidewalks Three lane Shifted 673 ft2 1 relocation required On existing alignment $8,100,000 (17,793 ft2 of bridge area) 4 years Feasible (requires separate pedestrian bridge) Bridge without sidewalks Three-lane Faster 574 ft2 1 relocation period required, or temporary support during construction With temporary Marolt detour $11,100,000 (24,557 ft2 of bridge area) 3 years Not feasible Sidewalk alternative Pedestrian Bridge[c] 791 ft2 1 relocation period Not applicable $2,500,000 < 1 year Not applicable Sidewalk alternative Three lane Shifted with Pedestrian Bridge 1,464 ft2 1 relocation period On existing alignment $10,600,000 4 years Not applicable 136 Analysis of Sidewalk Removal from the Castle Creek Bridge 17 [a] These costs do not represent complete Project costs, such as costs for ROW, TCE, mobilization, traffic control, site civil work, and other nonstructural items. Refer to Table 8 of the Feasibility Study for the cost estimates of the replacement alternatives with sidewalks. [b] Refer to Table 7 of the Feasibility Study for the construction duration of the replacement alternatives with sidewalks. [c] Excluding the utility impacts, the pedestrian bridge values are in addition to the vehicular bridge values. 137 Analysis of Sidewalk Removal from the Castle Creek Bridge 18 6. Conclusions and Recommendations Based on this analysis, conclusions and recommendations are as follows:  The existing sidewalks provide an important and highly used bicycle and pedestrian connection.  Federal and state policies dictate that removal of this connection would require providing a reasonable alternative route.  Two of the alternative routes analyzed are substantially out of direction compared to the current route and are therefore deemed unreasonable. The third alternative route—a parallel and separated pedestrian bridge—could be constructed to serve pedestrians along the current alignment and grade. However, this pedestrian bridge would increase Project costs, increase ROW acquisition, and present other construction impacts.  There is no significant benefit of sidewalk removal for ROW acquisition or utility construction.  There are no traditional phased construction options that accommodate two lanes of traffic on the existing alignment during construction without having ROW impacts. Based on this analysis, Jacobs recommends keeping sidewalks in the new three-lane bridge design. 7. References City of Aspen (City). 2019. Engineering Standards. January. https://www.aspen.gov/ DocumentCenter/View/505/Engineering-Standards-PDF?bidId=. City of Aspen (City). 2023. Aspen Parks & Trails [map]. May 26. https://mapaspen- cityofaspen.opendata.arcgis.com/documents/f0998cd2c8584cac820fa775efdab2e8/ explore. City of Aspen (City). 2024. Personal communication (letter) with the Colorado Department of Transportation (CDOT). May 7. Colorado Department of Transportation (CDOT). 1997. State Highway 82 Entrance to Aspen: Final Environmental Impact Statement, Section 4(f), Volume I. Project STA 082A008. August. Colorado Department of Transportation (CDOT). 2024. Personal communication (letter) with the City of Aspen. July 10. Mahaffey, Reghan, Aspen School District Transportation Director. 2024. Personal communication (email) with Terri Partch, Senior Project Manager, Jacobs. June 18. 138 Analysis of Sidewalk Removal from the Castle Creek Bridge 19 Ipsen, Todd and Annelies Van Vonno, Colorado Department of Transportation(CDOT). 2024. Personal communication (email) with Terri Partch, Senior Project Manager, Jacobs. July 3. Jacobs. 2024. State Highway (SH) 82 Over Castle Creek Bridge Feasibility Study. April. City of Aspen (City). 2016. Castle Creek/Hallam Street Connectivity Study: Living Lab Experiment and Hallam Street 30% Design Update (Memo from staff to the City Council). September 2. 139 Memorandum: Castle Creek Bridge Economic Impact Analysis 1 Memorandum Subject: Castle Creek Bridge Economic Impact Analysis Project Name: New Castle Creek Bridge Investigative Study with Revised Scope (the Project) Attention: From: Date: Copies to: City of Aspen (the City) Jacobs July 31, 2024 Project File 1. Introduction This memorandum presents an analysis of existing conditions and potential economic impacts associated with the construction of the replacement bridge. The analysis focuses on the Three-lane Shifted and Three-lane Faster bridge replacement options outlined in the SH 82 Over Castle Creek Bridge Feasibility Study (Jacobs 2024); the Entrance to Aspen Preferred Alternative, Splitshot alternative, and other alternatives are not assessed. The analysis also focuses on impacts during the construction period and does not estimate the longer-term operational impacts associated with the Project. The economic impact analysis estimates the following: How the Project construction may increase or decrease economic activity during the construction phase Economic impacts from construction delays, including user and traveler costs Potential economic benefits from bridge construction to the local and regional economy A survey was conducted of local businesses to understand how Project construction may impact their revenues. Survey results help inform the potential impacts to City tax revenues associated with changes to business activities. 2.Existing Conditions This section describes existing conditions in Aspen. 2.1 Overview Aspen is known for its natural beauty, outdoor recreation, and tourism. Its location in the Rocky Mountains has made it a premier year-round destination. The Aspen Chamber Resort Association (Aspen Chamber) states the following: “Aspen is nestled in the awe-inspiring Rocky Mountains. Here, visitors can enjoy renowned arts and culture, exceptional cuisine, world-class accommodations, and 140 Memorandum: Castle Creek Bridge Economic Impact Analysis 2 countless outdoor pursuits - all the makings for an extraordinary vacation experience…While Aspen gained recognition as a premier skiing destination, it wasn’t long before visitors began to explore and appreciate the area, sans snow. Spring, summer, and fall are ideal times for hiking, biking, and rafting. Exceptional dining, premier shopping, a variety of events and leading arts & culture draw people from around the world.” (Aspen Chamber 2024a) As well as its seasonal footfall for outdoor recreation, Aspen hosts regular events that bring more visitors into the city (Aspen Chamber 2024b). Standout annual events include the following:  Wintersköl  ESPN Winter X Games  Aspen Gay Ski Week  Jazz Aspen Snowmass (JAS) June Experience  Aspen Music Festival and School  Theatre Aspen Summer Series  The Annual Food and Wine Classic in Aspen  Aspen Ideas Festival  4th of July  JAS Labor Day Experience The Aspen Chamber undertook a 2022 study that identified the following key challenges for the City (Aspen Chamber 2022):  Staff shortages: Aspen is experiencing labor force shortages because of high housing costs combined with many jobs only lasting the duration of the busy seasons.  Mountain migration and gentrification: Many wealthy, high earners from across the county come to Aspen for its natural beauty. However, this inherently gentrifies the city. Furthermore, these individuals often have second homes in Aspen that are not primary residences, which could be interpreted as not fully integrating with the Aspen community.  Visitor pressure: The sheer volume of visitors during busy seasons can put a strain on the community, particularly when these visitors do not practice certain informal behaviors such as respecting the surrounding natural area.  Social inequality: There is concern within the working-class population of Aspen that the wealth created by the tourism sector is not benefiting them. This concern is worsened by the working class being priced out of Aspen by high costs of living.  Transportation management: Ongoing construction, growth in the region, and high tourism levels are increasing road traffic levels beyond capacity, putting a strain on transportation infrastructure.  Lack of economic diversification: Aspen’s economy is heavily focused on tourism, with development in other sectors being desirable. 141 Memorandum: Castle Creek Bridge Economic Impact Analysis 3 2.2 Population The U.S. Census Bureau provides annual estimates of the population of cities and communities within the State of Colorado in the form of the American Community Survey (ACS ). ACS population estimates for Aspen, Pitkin County, and the State of Colorado in 2010, 2015, 2020, and 2022 are shown in Table 2-1. The population in Aspen increased at a greater rate (2.9 %) between 2015 and 2020 than the wider county and state . However, in the recent years of 2020 to 2022, the population estimates in Aspen have decreased by 5% per year on average, in contrast to the increasing population of Colorado (1.4%). A potential explanation of this is the increased demand for accommodation in Aspen, largely driven by tourism. This could increase housing costs, thus pricing out locals from living in Aspen. Furthermore, an increased proportion of the existing housing stock being used for seasonal accommodation and second homes reduces the amount of accommodation available for permanent residents. The combination of these two factors may cause former Aspen residents to instead reside nearby, outside of Aspen . Table 2-1: Population Area Population Average Annual Growth Rate (%) 2010 2015 2020 2022 2010 to 2015 2015 to 2020 2020 to 2022 Aspen 6,658 6,740 7,721 6,952 0.2% 2.9% -5.0% Pitkin County 16,389 17,420 17,980 17,325 1.3% 0.6% -1.8% Colorado 5,049,071 5,456,574 5,684,926 5,839,926 1.6% 0.8% 1.4% Source: U.S. Census Bureau, 2010b; U.S. Census Bureau, 2015b; U.S. Census Bureau, 2020b; U.S. Census Bureau, 2022b. 2.3 Employment Two estimates of employment are typically used to describe employment in an area: (1) total civilian labor force and (2) employment by industry. Civilian labor force data reflect the employment status of individuals by place of residence and include people who are self-employed, employees on unpaid leave of absence, unpaid family workers, and household workers. Employment by industry data reflect jobs by place of work and exclude the self-employed, unpaid family workers, employees on leave of absence, and household workers. Individuals with more than one job are counted only once in the civilian labor force data, but they are counted for each job in the employment by industry data. 142 Memorandum: Castle Creek Bridge Economic Impact Analysis 4 2.3.1 Unemployment Rate Table 2-2 shows the civilian labor force characteristics for Aspen, Pitkin County, and the State of Colorado for select years. In terms of civilian labor force, the state overall has experienced a steady increase between 2010 and 2022; however, after 2020, both Pitkin County and Aspen experienced an unusual drop in labor force. Like the decrease in population, a potential explanation is that individuals residing outside of Aspen are commuting in. Between 2010 and 2015, the average unemployment rate increased more than sixfold in Aspen but decreased to 1% between 2015 and 2020, less than the county and state rates. In recent years between 2020 and 2022, the Aspen and Colorado unemployment rates have converged slightly. Table 2-2: Civilian Labor Force and Unemployment Rate Area Civilian Labor Force Unemployment Rate (%) 2010 2015 2020 2022 2010 2015 2020 2022 Aspen 4,354 4,391 5,311 4,693 0.9% 5.9% 1.0% 1.8% Pitkin County 10,726 11,151 12,137 10,720 1.8% 5.8% 2.7% 1.5% Colorado 2,714,224 2,916,718 3,079,769 3,244,388 6.8% 3.5% 3.1% 2.4% Source: U.S. Census Bureau, 2010a; U.S. Census Bureau, 2015a; U.S. Census Bureau, 2020a; U.S. Census Bureau, 2022a. Figure 2-1: Average Annual Unemployment Rate, 2010 to 2022 Trends in the annual unemployment rate for Aspen, Pitkin County, and the State of Colorado are shown on Figure 2-1. In Colorado, the annual unemployment rate peaked in 2010, at the height of the Great Recession, before declining continuously 0.0% 1.0% 2.0% 3.0% 4.0% 5.0% 6.0% 7.0% 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 Aspen Pitkin County Colorado 143 Memorandum: Castle Creek Bridge Economic Impact Analysis 5 thereafter. The unemployment rate increased again in 2020 and 2021 following the COVID-19 global pandemic, before starting to decline again in 2022. As a contrast to the state, the Aspen and Pitkin County unemployment rates follow a separate trend, increasing from 2010 to their peak in 2015. After 2015, these rates generally decreased, suggesting that the pandemic led to an influx of employees leaving larger urban areas to work remotely in the county and city, mirroring national trends. 2.3.2 Employment by Industry Table 2-3 presents the annual full-time and part-time employment by industry in Aspen for 2010, 2016, and 2022. In terms of total industry employment, the combined arts, entertainment, recreation, and accommodation/food services sector is by far the largest industry in Aspen in all observed years, driven by Aspen being a destination for outdoor recreation tourism. In terms of average annual growth rates, most sectors have experienced growth, but others have lost jobs (for example, agriculture, construction, wholesale trade, and retail trade). Between 2010 and 2016, the manufacturing sector experienced the greatest average annual growth rate (40.4%), followed by the other services sector (26.9%), with both maintaining similar employment levels through to 2022. However, between 2016 and 2022, the transportation, warehousing, and utilities sector experienced the greatest average annual growth rate (40.5%), followed by the construction sector (27.8%). Table 2-3: Employment Numbers by Industry in Aspen Industry Sector 2010 2016 2022 2010 to 2016 2016 to 2022 Agriculture, forestry, fishing and hunting, and mining Not available 50 25 Not available -8.3% Construction 350 57 152 -14.0% 27.8% Manufacturing 40 137 147 40.4% 1.2% Wholesale trade 121 36 48 -11.7% 5.6% Retail trade 688 477 453 -5.1% -0.8% Transportation, warehousing, and utilities 87 96 329 1.7% 40.5% Information 185 79 128 -9.5% 10.3% Finance, insurance, real estate, and rental and leasing 393 589 493 8.3% -2.7% Professional, scientific, management, administrative, and waste management services 624 655 495 0.8% -4.1% 144 Memorandum: Castle Creek Bridge Economic Impact Analysis 6 Industry Sector 2010 2016 2022 2010 to 2016 2016 to 2022 Educational services, health care, and social assistance 462 714 802 9.1% 2.1% Arts, entertainment, recreation, and accommodation and food services 1,096 1,068 1,100 -0.4% 0.5% Other services, except public administration 39 102 195 26.9% 15.2% Public administration 217 176 215 -3.1% 3.7% Total Industry Employment 4,302 4,236 4,582 -0.3% 1.4% Source: U.S. Census Bureau, 2010a; U.S. Census Bureau, 2016; U.S. Census Bureau, 2022a. Figure 2-2 compares the proportions each industry holds of total employment in 2022 for Aspen, Pitkin County, and Colorado. It is again clear that the arts, entertainment, recreation, and accommodation and food services sector remains the largest industry (24.0%), considerably larger than in wider Colorado (9.2%). Conversely, in Aspen, the construction (3.3%) and manufacturing (3.2%) sectors are among the industries less represented than the Colorado average (8.0 % and 7.2%, respectively). 145 Memorandum: Castle Creek Bridge Economic Impact Analysis 7 Figure 2-2: Proportional Employment by Industry in 2022 Source: U.S. Census Bureau, 2022a. 2.4 Median Household Income Table 2-4 shows the real median household incomes (in 2022 dollars) for Aspen, Pitkin County, and Colorado. Incomes in Aspen are consistently more than the Colorado average in all observed years; however, they are also consistently less than the Pitkin County average. Between 2010 and 2020, real median household incomes grew steadil y in Aspen, Pitkin County, and Colorado (between 1.5 and 3.6%). Between 2020 and 2022, all geographies experienced considerably higher average annual income growth rates, with Aspen having the highest of these (10.7%). 0%5%10%15%20%25% Agriculture, forestry, fishing and hunting, and mining Construction Manufacturing Wholesale trade Retail trade Transportation and warehousing, and utilities Information Finance and insurance, and real estate and rental and leasing Professional, scientific, and management, and administrative and waste management services Educational services, and health care and social assistance Arts, entertainment, and recreation, and accommodation and food services Other services, except public administration Public administration Colorado Pitkin County Aspen City 146 Memorandum: Castle Creek Bridge Economic Impact Analysis 8 Table 2-4: Median Household Income, 2010 to 2022 Area 2010 2015 2020 2022 Average Annual Growth Rate (%) 2010 to 2015 2015 to 2020 2020 to 2022 Aspen $62,458 $67,164 $77,669 $94,338 1.5% 3.1% 10.7% Pitkin County $64,502 $71,196 $82,455 $96,123 2.1% 3.2% 8.3% Colorado $54,046 $63,909 $75,231 $89,302 3.6% 3.5% 9.4% Source: U.S. Census Bureau, 2010c; U.S. Census Bureau, 2015c; U.S. Census Bureau, 2020c; U.S. Census Bureau, 2022c. 2.5 City of Aspen Financials Table 2-5 presents the planned revenues for the City in 2024 based on its 2024 proposed budget (City 2023). The City anticipates receiving $191 million in revenue from a range of sources, including various taxes and charges. The greatest revenue source is charges for services (20%), followed by city sales tax (14%). Overall, tax makes up 50% of the City’s revenues. Table 2-5: City of Aspen Planned Revenue By Category, 2024 Revenue by Category 2024 % of Total Gross Revenue General Property Taxes $10,734,100 6% County Sales Tax $17,913,000 9% City Sales Tax $26,135,200 14% Lodging Tax $6,460,000 3% Public Education Sales Tax $4,485,360 2% City Tobacco Tax $305,000 0% Other Taxes $1,772,000 1% Selective Sales and Use Taxes $1,000,000 1% Total Real Estate Transfer Tax $19,400,000 10% City Excise tax $7,900,000 4% General Revenue (Taxes) $96,104,660 50% Licenses and Permits $6,819,630 4% Intergovernmental Revenues $860,190 0% Charges for Services $37,256,042 20% 147 Memorandum: Castle Creek Bridge Economic Impact Analysis 9 Revenue by Category 2024 % of Total Gross Revenue Other Inflows $18,336,626 10% Other Revenue Sources $13,931,278 7% General Transfers In $17,724,150 9% Total Gross Revenue $191,032,576 100% Source: City, 2023. Figure 2-3 shows the proportions each tax category makes up of total tax revenue. The tax revenues are city sales tax (27%), followed by real estate transfer tax (20%), and county sales tax (19%). The combination of city and county sales taxes makes up 46% of total tax revenue. Figure 2-3: City of Aspen Tax Revenue Proportions 3. Construction Impacts The following sections discuss how Project construction may increase or decrease economic activity during the construction phase. General Property Taxes 11% County Sales Tax 19% City Sales Tax 27%Lodging Tax 7% Public Education Sales Tax 5% City Tobacco Tax 0% Other Taxes 2% Selective Sales and Use Taxes 1% Total Real Estate Transfer Tax 20% City Excise Tax 8% 148 Memorandum: Castle Creek Bridge Economic Impact Analysis 10 3.1 Construction Cost Estimates Table 3-1 presents the construction cost estimates for the bridge replacement options being considered. The Three-lane Faster option in year of expenditure dollars is nearly $96 million, whereas the Three-lane Shifted option is approximately $81 million. The Three-lane Faster option is expected to be built over a 3-year period, whereas the Three-lane Shifted option will take 4 years. Table 3-1: Summary of Project Cost and Construction Duration Item Option: Three-lane Faster Option Three-lane Shifted Overall Project Cost (2024 dollars) $81.85 million $69.28 million Overall Project Cost (2028 dollars) $95.75 million $81.05 million Construction Duration 3 years 4 years Source: Jacobs, 2024. 3.2 Construction Travel Delay and Costs Construction-related delays would result in some congestion or traffic halts that will increase user costs for residents and visitors. The construction-related delays would add additional vehicle hours traveled (VHT) during the construction period. Although Project construction would only occur over designated months, the roadway impacts are expected to be year-round. Depending on the alternative selected, construction is expected to last betw een six to eight construction seasons, and the delay impacts are expected to last 3 to 4 years. Delay costs can be estimated using input values provided by the U.S. Department of Transportation’s (DOT’s) Benefit-Cost Analysis Guidance for Discretionary Grant Programs (BCA Guidance) (DOT 2023). The assumptions and inputs used in the user costs calculations are standard inputs and values from DOT’s BCA Guidance, such as vehicle occupancy rates and the value of time. Mode split between personal vehicles and commercial vehicles and the estimated travel delay in the network was estimated by Jacobs traffic engineers. The analysis compares the two build scenarios to existing conditions to define the delay during construction. The overall BCA methodology includes the following steps:  Define existing conditions and conditions during construction for the build alternatives.  Estimate delay during Project construction. The construction period will be 3 years for Three-lane Faster option and 4 years for the Three-lane Shifted option.  Input DOT-recommended monetized values for travel time and operating costs.  Input mode split of 97.5% all-purpose vehicles and 2.5% commercial vehicles. 149 Memorandum: Castle Creek Bridge Economic Impact Analysis 11  Use dollar values in real 2022 dollars.  A real discount rate of 3.1% is recommended in the DOT guidance document to discount future costs into 2022 dollars. The DOT BCA Guidance methodology estimates vehicle operating costs on a per mile basis, and the mileage during construction will be the same as under existing conditions. Thus, potential changes in vehicle operating costs were not evaluated in this analysis. Traffic delay was annualized using traffic counts and predictive delay estimates. Traffic counts were collected in 15-minute intervals on the existing Castle Creek Bridge on May 20, 2024. Traffic count data between 1999 and 2023 were provided by the City (City, various years). Additional traffic delay from work zone speed reduction along the Project bridge was estimated to be 5 minutes in each direction during traffic peaks and 20 seconds during off-peak. Annualization of this delay was estimated based on the traffic count data available. The longest delays are estimated to occur for morning inbound and afternoon outbound travel during the peak travel period s. The delay is estimated to be approximately 5 minutes. The travel delay during the morning peak outbound, afternoon peak inbound, and off-peak travel is expected to be approximately 20 seconds. Table 3-2 presents the annual inbound and outbound vehicle hour delay associated with construction of the Project. The annual delay is the same for the Three-lane Shifted and the Three-lane Faster alternatives. The traffic delay calculations are provided in Attachment 1. Table 3-2: Annualized Construction-related Vehicle Hours Traveled Direction Annualized VHT Inbound 98,681 Outbound 86,817 Total 185,498 The value of construction delay was calculated in accordance with the DOT BCA Guidance (DOT 2024). For all-purpose vehicles, a rate of $19.60 per person-hour (2022 dollars) was used for all-purpose local travel (automobile) and $33.50 was used for commercial vehicles. The average occupancy was assumed to be 1.67 for all- purpose vehicles and 1.00 for commercial. The reported mode split is 97.5% all- purpose vehicle and 2.5% commercial. Construction-related travel delays are expected with both the Three-lane Faster scenario and the Three-lane Shifted scenario. The estimated delays during construction are summarized in Table 3-3. The value of the delay is for the entire construction period for both scenarios. Applying the appropriate traffic inputs and DOT values estimated the net present value of the additional user costs over the 150 Memorandum: Castle Creek Bridge Economic Impact Analysis 12 entire construction period would be approximately $14.7 million for the Three-lane Faster scenario and $19.3 million for the Three-lane Shifted option. Table 3-3: Value of Construction-related Delay Vehicle Type Three-lane Faster NPV (2022 dollars) Three-lane Shifted NPV (2022 dollars) All-Purpose Vehicle $14,347,005 $18,844,677 Commercial Vehicle $376,503 $494,534 Total Value of Delay) $14,723,509 $19,339,211 NPV = net present value 3.3 Business Survey Results The City conducted a survey of local businesses to assess the potential impacts of the Project. The survey data will inform the (IMpact Analysis for PLANning) (IMPLAN) economic model, which will estimate Project effects on economic activity and tax revenue. The survey covered various Project-related topics, but the IMPLAN model primarily relies on responses to the following:  Primary industry: Retail was the dominant industry among respondents (32.5%), followed by food (15%), real estate (12.5%), arts and accommodations (both at 7.5%), and tourism (5%). The remaining industries each represented 2.5% of the respondents.  Revenue impact: Most businesses anticipate a significant impact on revenue during construction, with 37% expecting major effects and 34% expecting modest ones. However, 24% reported no anticipated impact.  Impact duration: 76% of respondents expect their business to be affected throughout the entire construction period (estimated at 3 to 4 years), whereas 24% anticipate no impact. The City partnered with the Aspen Chamber to distribute the survey to over 100 member businesses via email, and City staff members made direct connections with businesses to let them know about the survey. As of July 19, 2024, 42 businesses responded, and the survey closed on that date. Refer to Attachment 2 for detailed survey results. 3.4 Construction Spending Impacts This section describes the economic impacts associated the Project construction spending and the potential impacts to tourism during the construction phase. It describes the economic impact analysis methodology used to evaluate these impacts, including the inputs and assumptions, and the results from the IMPLAN model runs. 151 Memorandum: Castle Creek Bridge Economic Impact Analysis 13 3.4.1 Methodology and Approach Regional economics is the study of the economy of a small region. Regional economic impacts result from changes in the economy of the region. The magnitude of the economic impacts is determined by the interactions between linkages within the local and regional economy and the leakages 1 from the regional to the larger economy. Economic linkages are the relationships between industries, businesses, factors of production (such as labor and capital), and government created by trade and other exchange, such as taxes, within and among regions. Economic linkages create multiplier effects in a regional economy as money is circulated by trade. The magnitudes of impacts resulting from economic linkages are limited by the amount of leakage that occurs within the region. Economic leakages are a measure of the income shares spent outside of the region. Thus, the more the economic leakage, the less the multiplier effect. Economic leakages are generally greater the smaller the regional economy. For example, the economic leakages for a city are greater than those for a county, which are greater than those for the state, which are greater than those for a nation. For the analysis presented in this memorandum, the local and regional economy is Pitkin County, Colorado, and the larger economy is the rest of the state and/or the nation. Several regional economic analysis modeling systems (consisting of data, as well as analytical software) are available for use in regional economic analysis—for example, Regional Economic Models Inc. (REMI), Regional Industrial Multiplier System II (RIMS II), and IMPLAN. This analysis used IMPLAN, a computer database and modeling system used to create input-output models for any U.S. county or combination of U.S. counties. The IMPLAN model is the most widely used input-output impact model system in the U.S. It is much more than a set of multipliers; it provides users with the ability to define industries, economic relationships, and projects to be analyzed. It can be customized for any county, region, or state and used to assess the “ripple effects” or “multiplier effects” caused by increasing or decreasing spending in various parts of the economy. This is used primarily to assess the economic impacts of facilities or industries, or changes in their level of activity in an area. IMPLAN is a static model that estimates impacts for a snapshot in time when the impacts are expected to occur, based on the makeup of the economy at the time of the underlying IMPLAN data. IMPLAN measures the initial impact to the economy but does not consider long-term adjustments as labor and capital move into alternative uses. This approach was used to estimate the economic impacts associated with the construction of the Castle Creek Bridge and anticipated reduction in tourism during bridge construction. Realistically, the structure of the economy will adapt and change; therefore, the IMPLAN results can only be used to compare relative changes 1 Economic leakage refers to spending being diverted away from a local economy, for example, when local businesses or consumers choose to make purchases from outside of the local economy. 152 Memorandum: Castle Creek Bridge Economic Impact Analysis 14 between the existing condition and the construction phase of the Project and cannot be used to predict or forecast future employment, labor income, or output (sales). Input-output models measure commodity flows from producers to intermediate and final consumers. Purchases for final use (final demand) drive the model. Industries produce goods and services for final demand and purchase goods and services from other producers. These other producers, in turn, purchase goods and services. This buying of goods and services (indirect purchases) continues until leakages from the analysis area (imports and value added) stop the cycle. These indirect and induced effects (the effects of household spending) can be mathematically derived using a set of multipliers. The multipliers describe the change in output for each regional industry caused by a $1 change in final demand. Figure 3-1 illustrates the concept of input-output modeling. Figure 3-1: Input-output Modeling Concept 153 Memorandum: Castle Creek Bridge Economic Impact Analysis 15 The IMPLAN model package includes state-level or county-level data to describe the local economy in a given year and an online platform that allows users to input more refined and/or accurate input data reflecting the regional economy. The economic impacts associated with the construction phase of the Project were evaluated using the IMPLAN model of Pitkin County. The model uses 2022 IMPLAN data to estimate the secondary (indirect and induced) regional employment and income; these data were the most current available at the time of this analysis and represent the economy in Pitkin County in 2022. 3.4.2 Economic Impacts of Castle Creek Bridge Construction This section presents the regional economic impacts of Project construction and anticipated reduction in tourism during bridge construction using the IMPLAN model and the 2022 IMPLAN data for Pitkin County. 3.4.2.1 Assumptions and Cost Inputs: Construction Project construction would generate a range of short-term effects during the construction phase. Because the IMPLAN model is an annual model that evaluates the regional economic effects of changes in local expenditures, it was necessary to identify which of the Project’s costs would be spent on Pitkin County-sourced material and labor inputs. Table 3-4 presents the total rough order of magnitude estimates of Project costs in 2024 dollars for each of the two build alternatives. Because the accuracy of the results depends on the accuracy of the inputs, the cost estimates are considered preliminary and could change as the engineering design is developed and refined. Additionally, the cost estimates were converted to 2022 dollars using the implicit gross domestic product (GDP) deflator, which is necessary for them to be used as the direct input into the 2022 IMPLAN model (BEA n.d.). Table 3-4: Total Project Costs Cost Three-lane Faster Three-lane Shifted Overall Project Cost (2024 dollars) $81,850,000 $69,280,000 Overall Project Cost (2022 dollars) $75,869,000 $64,217,000 Based on information derived from similar projects in the area, the following assumptions were used to determine the Pitkin County portion of project cost:  Between 5% and 10% of the total Project cost is assumed to be spent within Pitkin County.  Of these local expenditures, 60% are assumed to be labor expenditures, and 40% are assumed to be expenditures on materials, supplies, services, and other nonlabor costs. 154 Memorandum: Castle Creek Bridge Economic Impact Analysis 16 Table 3-5 shows the breakdown of the costs in 2024 dollars based on the previously stated assumptions. The lower bound estimate for the portion of the Project expenditures during construction within Pitkin County are represented as 5% of the Project cost estimates, and the upper bound for the local portion of the Project expenditures within the county are represented as 10% of the Project cost estimates. In addition to showing the lower and higher bounds for the local expenditures, Table 3-5 also shows the proportion of these local costs that are labor and nonlabor (for example, materials, supplies, and services) expenditures. Table 3-5: Breakdown of Total Local Project Costs (in 2024 Dollars) Bound Estimate Category Three-lane Faster Three-lane Shifted Lower Local (within Pitkin County) Estimate (5%) $4,093,000[a] $3,464,000 Lower Labor (60%) $2,456,000[b] $2,078,000 Lower Nonlabor (40%) $1,637,000[c] $1,386,000 Upper Local (within Pitkin County) Estimate (10%) $8,185,000[d] $6,928,000 Upper Labor (60%) $4,911,000[e] $4,157,000 Upper Nonlabor (40%) $3,274,000[f] $2,771,000 [a] $4,093,000 = $75,869,000 x 5% [b] $2,456,000 = $4,093,000 x 60% [c] $1,637,000 = $4,093,000 x 40% [d] $8,185,000 = $64,217,000 x 10% [e] $4,911,000 = $8,185,000 x 60% [f] $3,274,000 = $8,185,000 x 40% Note: Costs estimates shown for the Three-lane Shifted alternative were determined using calculations similar to those shown for the Three-lane Faster alternative in the table. The local cost estimates shown in Table 3-5 were divided by the duration of the construction period, which was assumed to be 3 years for the Three-lane Faster alternative and 4 years for the Three-laned Shifted alternative. Table 3-6 summarizes the resulting annual local construction cost estimates in 2024 dollars. These annual construction cost estimates were converted to 2022 dollars using the implicit GDP deflator, which is necessary for them to be used as the direct input into the 2022 IMPLAN model (BEA n.d.). Table 3-7 presents these annual direct local expenditures in 2022 dollars. 155 Memorandum: Castle Creek Bridge Economic Impact Analysis 17 Table 3-6: Breakdown of Annual Direct Local Construction Costs (in 2024 Dollars) Bound Estimate Item Three-lane Faster Three-lane Shifted Lower Local (within Pitkin County) Estimate (5%) $1,364,000 $866,000 Lower Labor (60%) $819,000 $520,000 Lower Nonlabor (40%) $546,000 $347,000 Upper Local (within Pitkin County) Estimate (10%) $2,728,000 $1,732,000 Upper Labor (60%) $1,637,000 $1,039,000 Upper Nonlabor (40%) $1,091,000 $693,000 Table 3-7: Breakdown of Annual Direct Local Construction Costs (in 2022 Dollars) Bound Estimate Item Three-lane Faster Three-lane Shifted Lower Local (within Pitkin County) Estimate (5%) $1,264,000 $803,000 Lower Labor (60%) $759,000 $482,000 Lower Nonlabor (40%) $506,000 $321,000 Upper Local (within Pitkin County) Estimate (10%) $2,529,000 $1,605,000 Upper Labor (60%) $1,517,000 $963,000 Upper Nonlabor (40%) $1,012,000 $642,000 The labor and material cost estimates were identified separately and run through the corresponding IMPLAN sector, which for this Project is IMPLAN Sector 54, Construction of New Highways and Streets. The results of the IMPLAN model runs, which are described in Section 3.2, are the annual indirect and induced employment and income impacts associated with Project construction. To estimate the annual direct local construction workforce under each construction alternative (that is, Three-lane Faster and Three-lane Shifted), the following assumptions were used:  The average mean hourly construction wage for all construction occupations in Colorado in May 2022 (the most recent available data) of $29.35 was adjusted to $31.66 in 2024 dollars using the implicit GDP price deflator (BLS 2023; BEA n.d.).  Assuming 35% in benefits, the average mean hourly construction wage in 2024 dollars including benefits was estimated at about $43, and the annual construction salary including benefits was estimated at about $89,000. Based on the annual construction salary, the annual direct full-time equivalent (FTE) construction jobs in the county are as shown in Table 3-8. This represents the number of workers on average that would be employed during Project construction. These 156 Memorandum: Castle Creek Bridge Economic Impact Analysis 18 numbers were derived by dividing direct annual labor costs in 2024 dollars from Table 3-6 by the annual construction salary of $89,000. Table 3-8: Direct Annual Full-time Equivalent Jobs Annual Direct FTE Three-lane Faster Three-lane Shifted Based on lower bound of annual labor costs 9[a] 6 Based on upper bound of annual labor costs 18[b] 12 [a] Direct FTE = $819,000 divided by $89,000 = 9 [b] Direct FTE = $1,637,000 divided by $89,000 = 18 Note: Costs estimates shown for the Three-lane Shifted alternative were determined using calculations similar to those shown for the Three-lane Faster alternative in the table. 3.4.2.2 Assumptions : Tourism Project construction is anticipated to result in a reduction in business activity. Based on the estimated traffic delays and business survey results discussed in Section 3.3, business reduction is assumed to be between 2% and 5% and to primarily affect the retail, food, accommodation, recreation (tourism and arts), and real estate sectors. Output in the IMPLAN sectors corresponding to the retail, food, accommodation, recreation, and real estate sectors were reduced by 2% and 5%. The results from the IMPLAN model are summarized in the following section. 3.4.3 Results The economic impacts associated with construction expenditures and those associated with the reduction in business are summarized in Section 3.4.4.1 and 3.4.4.2, respectively. 3.4.3.1 Construction Impacts This section presents the regional economic impacts associated with construction spending using the IMPLAN model and the 2022 IMPLAN data for Pitkin County. Three-lane Faster Construction of the Three-lane Faster alternative is expected to take 3 years. Table 3-9 shows the annual direct and secondary (indirect and induced) economic impacts within Pitkin County associated with the construction of this alternative. Because the impacts were evaluated for a range of annual direct cost inputs, the results are presented as a range of values whereby the lower value corresponds to the lower cost input and the higher value corresponds to the higher cost input. 157 Memorandum: Castle Creek Bridge Economic Impact Analysis 19 Table 3-9: Annual Regional Employment and Labor Income Associated with Construction, Three-lane Faster Impact Employment (FTEs)[a] Labor Income (thousands, 2024 dollars)[b] Direct 10 to 20 $819 to $1,637 Indirect 10 to 10 $469 to $938 Induced 0 $31 to $62 Total 20 to 30 $1,319 to $2,637 Source: IMPLAN, 2024. [a] FTEs rounded to the nearest 10 jobs. [b] Labor Income shown is IMPLAN’s Employee Compensation, which includes total payroll cost of the employee paid by the employer. It includes wage and salary plus benefits and payroll taxes. Table 3-9 demonstrates that, in addition to the annual direct 10 to 20 FTE jobs, the Project construction phase under the Three-lane Faster alternative would result in indirect employment of 10 FTEs and average induced employment of less than 0.5 FTE within Pitkin County. The total annual construction employment within Pitkin County is estimated to be between 20 and 30 FTEs for each of the 3 years of construction. As expected, the increase in regional employment would be accompanied by increased levels of labor income within Pitkin County (Table 3-9). Construction of Three-lane Faster alternative is expected to result in about $0.8 million to $1.6 million in annual direct labor income. The annual indirect labor income is estimated at about $0.5 million to about $0.9 million, and the annual induced labor income is estimated to be between $31,000 and $62,000. The total annual labor income within Pitkin County is estimated to be between $1.3 million and $2.6 million. All estimates are in 2024 dollars. Three-lane Shifted Construction of the Three-lane Shifted alternative is expected to take 4 years. Table 3-10 shows the annual direct and secondary (indirect and induced) economic impacts within Pitkin County associated with the construction of Three-lane Shifted alternative. Table 3-10 shows that, in addition to the annual direct 10 FTE jobs, the Project construction phase under the Three-lane Shifted alternative would result in annual indirect employment of 10 FTEs and annual induced employment of 10 to 20 FTEs within Pitkin County. The total annual construction employment within Pitkin County is estimated to be between 10 and 20 FTEs for each of the 4 years of construction. 158 Memorandum: Castle Creek Bridge Economic Impact Analysis 20 Table 3-10: Regional Employment and Labor Income Associated with Construction, Three-lane Shifted Impact Employment (FTEs)[a] Labor Income (thousands 2024 dollars)[b],[c] Direct 10 to 10 $520 to $1,039 Indirect 0 to 10 $298 to $595 Induced 0 $20 to $40 Total 10 to 20 $837 to $1,674 Source: IMPLAN, 2024. [a] FTEs rounded to the nearest 10 jobs. [b] Labor Income shown is IMPLAN’s Employee Compensation, which includes total payroll cost of the employee paid by the employer. It includes wage and salary plus benefits and payroll taxes. [c] Labor income is rounded to the nearest $1,000. As expected, the increase in regional employment would be accompanied by increased levels of labor income within Pitkin County (Table 3-10). Construction of Three-lane Shifted alternative is expected to result in about $0.5 million to $1.0 million in annual direct labor income. The annual indirect labor income is estimated to be between $0.3 million and $0.6 million, and the annual induced labor income is estimated to be between $20,000 and $40,000. The total annual labor income within Pitkin County is estimated to be between $0.8 million and $1.7 million. All estimates are in 2024 dollars. 3.4.3.2 Tourism Impacts Table 3-11 shows the annual direct and secondary (indirect and induced) economic impacts within Pitkin County associated with a 2% and a 5% reduction in business. The results are presented as a range of values whereby the lower value corresponds to the 2% reduction and the higher value corresponds to the 5% reduction in business. The potential annual impact to the tourism sector would be the same for each of the bridge replacement alternatives and would occur during each year of construction. The Three-Lane Shifted alternative is estimated to take one year longer to construct thus the impacts would be greater than for the Three-Lane Faster alternative. 159 Memorandum: Castle Creek Bridge Economic Impact Analysis 21 Table 3-11: Regional Employment and Labor Income Associated with Loss in Tourism Business Impact Employment (FTEs)[a] Labor Income (millions 2024$)[b],[c] Direct -120 to -310 -$7.5 to -$18.8 Indirect -50 to -120 -$3.0 to -$7.4 Induced -10 to -20 -0.6 to -$1.5 Total -180 to -450 to -11.1 to -$27.8 Source: IMPLAN, 2024. [a] FTEs rounded to the nearest 10 jobs. [b] Labor Income shown is IMPLAN’s Employee Compensation, which includes total payroll cost of the employee paid by the employer. It includes wage and salary plus benefits and payroll taxes. [c] Labor income is rounded to the nearest $1 million. Table 3-11 illustrates that, in addition to the annual direct loss of 120 to 310 FTE jobs in the tourism-related sectors within Pitkin County, Project construction is also likely to result in a loss of 50 to 120 FTEs in indirect jobs and a loss of 10 to 20 FTEs in induced jobs. The total annual employment loss within Pitkin County during the 3-year or 4-year construction period is expected to be between 180 and 450 FTEs. As expected, the loss in regional employment would be accompanied by decreased levels of labor income within Pitkin County (Table 3-11). The Project construction phase is expected to result in annual direct labor income losses ranging between $7.5 million and $18.8 million. The loss in annual indirect labor income is estimated to be about $3.0 million to $7.8 million, and the loss in annual induced labor income is estimated to be between $0.6 million and $1.5 million. The loss in total annual labor income within Pitkin County is estimated to be about $11.1 million to $27.8 million. All estimates are in 2024 dollars. Potential Impacts to Tax Revenues The potential impacts to tax revenues were estimated at the county level using the Pitkin County IMPLAN model assuming a 2% and a 5% reduction in tourism-related business. Pitkin County is expected to lose between $0.3 million and $0.7 million in annual sales tax revenues during the Project construction phase because of disruption to the tourism industry. The lower value of this range corresponds to the assumed reduction of 2% in tourism-related business reduction, and higher value corresponds to the 5% reduction in tourism-related business. Some of the estimated increases in jobs and earnings in the construction industry will likely be filled by Aspen residents. While impacts on the tourism sector are reported for the County, a majority of the impacts would likely affect businesses in Aspen 160 Memorandum: Castle Creek Bridge Economic Impact Analysis 22 because that is where the effects of the construction related traffic delay will be experienced. Impacts to sales tax revenues are reported for the County. It is expected the City would experience a reduction in sales tax revenues if there were a decrease in business activity related to the construction of the Project; the potential impacts would likely be less than those reported for the County. 4. Summary Project Construction would generate a range of short-term effects during the construction phase. The Three-lane Faster alternative would be constructed over a 3-year period, whereas the Three-lane Shifted alternative would take 4 years to complete. Annual construction-related delay is expected to be similar for each alternative but would last longer for the Three -lane Shifted alternative. The construction delay would result in additional travel time for all-purpose and commercial vehicles, resulting in approximately $6 million per year of added travel time. Nearly 98% of the additional delay is expected to be for all-purpose vehicles. The Project would also have regional economic impacts associated with construction spending and potential impacts on local and regional business activity. A survey of local businesses helped inform the potential impact on business activity. Some businesses reported concerns that the Project construction would have adverse impacts on sales, whereas other businesses suggested the Project would not impact their revenues. A range of 2 to 5% reduction in sales was analyzed to illustrate the potential impact. The estimated annual regional economic impacts include the following:  For the Three-lane Faster alternative, the construction sector will experience an additional 10 to 20 jobs annually and $0.8 million to 1.6 million in labor income. These direct jobs and income in the construction sector generate 10 secondary 2 jobs and $0.5 million to $1.0 million in secondary labor income, annually in Pitkin County.  For the Three-lane Shifted alternative, the construction sector will experience an additional 10 jobs annually and $0.5 to $1.0 million in labor income. These direct jobs and income in the construction sector generate 10 secondary jobs and $0.3 million to $0.7 million in secondary labor income annually, in Pitkin County.  For both alternatives, the tourism sector will experience an annual decrease in direct employment of 120 to 310jobs, resulting in an annual reduction of direct labor income of $7.5 to $18.8 million. These annual direct reductions in employment and labor income in the tourism-related sectors result in secondary employment losses of 60 to 140 jobs and secondary labor income losses of $3.6 million to $9.0 million, annually in Pitkin County.  Reductions in sales tax revenue range from $03 to $0.7 million. 2 Secondary = indirect + induced 161 Memorandum: Castle Creek Bridge Economic Impact Analysis 23 Based on the results of the traffic analysis that show relatively low levels of additional travel delay when compared to existing conditions, the impacts on tourism and tax revenues are anticipated to be on the lower end of the range reported in this analysis. 5. References Aspen Chamber Resort Association (Aspen Chamber). 2022. Aspen Destination Management Plan (ADMP) 2022-2027. https://aspenchamber.imagerelay.com/ share/ac4b661aa7ad420dbaf7a7d56aa61ca2. Aspen Chamber Resort Association (Aspen Chamber). n.d.a. “About Aspen.” Accessed July 29, 2024. https://aspenchamber.org/about. Aspen Chamber Resort Association (Aspen Chamber). n.d.b. “Top Yearly Events.” Accessed July 29, 2024. https://aspenchamber.org/blog/top-yearly-events-aspen. City of Aspen (City). Monthly Traffic Counts. Various Years, 1999-2024. City of Aspen (City). 2023. 2024 Proposed Budget. September 25. https://www.aspen.gov/DocumentCenter/View/11394/2024-Proposed-Budget--- Digital-Book-PDF. IMPLAN Group LLC (IMPLAN). 2024. IMPLAN Model data and software. https://implan.com/. Jacobs. 2024. SH 82 Over Castle Creek Bridge Feasibility Study. Prepared for the City of Aspen. U.S. Bureau of Economic Analysis (BEA). n.d. “Table 1.1.9, Implicit Price Deflators for Gross Domestic Product.” National GDP & Personal Income. Accessed July 11, 2024. https://www.bea.gov/itable/national-gdp-and-personal-income. U.S. Bureau of Labor Statistics (BLS). 2023. May 2022 State Occupational Employment and Wage Estimates. https://www.bls.gov/oes/2022/may/oessrcst.htm. U.S. Census Bureau. 2010a. “Table DP03, Selected Economic Characteristics.” American Community Survey, 5-Year Estimates Data Profiles. Aspen city, Colorado; 2010. https://data.census.gov/table/ACSDP5Y2010.DP03?q=employment in aspen city in 2010&g=160XX00US0803620. U.S. Census Bureau. 2010b. “Table P1, Race.” Race, Decennial Census, Redistricting Data (PL 94-171). Aspen city, Colorado; 2010. https://data.census.gov/table/ DECENNIALPL2010.P1?q=Aspen city population in 2010&g=160XX00US0803620. U.S. Census Bureau. 2010c. “Table S1901, Income in the Past 12 Months (in 2010 Inflation-adjusted Dollars).” American Community Survey, 5-Year Estimates Subject Tables. Aspen city, Colorado; 2010. https://data.census.gov/table/ ACSST5Y2010.S1901?q=income in aspen city in 2010&g=160XX00US0803620. U.S. Census Bureau. 2015a. “Table DP03, Selected Economic Characteristics.” American Community Survey, 5-Year Estimates Data Profiles. Aspen city, Colorado; 162 Memorandum: Castle Creek Bridge Economic Impact Analysis 24 2015. https://data.census.gov/table/ACSDP5Y2015.DP03?q=employment in aspen city&g=160XX00US0803620. U.S. Census Bureau. 2015b. “Table DP05, ACS Demographic and Housing Estimates.” American Community Survey, 5-Year Estimates Data Profiles. Aspen city, Colorado; 2015. https://data.census.gov/table/ACSDP5Y2015.DP05?q=Aspen city population&g=160XX00US0803620. U.S. Census Bureau. 2015c. “Table S1901, Income in the Past 12 Months (in 2015 Inflation-adjusted Dollars).” American Community Survey, 5-Year Estimates Subject Tables. Aspen city, Colorado; 2015. https://data.census.gov/table/ ACSST5Y2015.S1901?q=income in aspen city&g=160XX00US0803620. U.S. Census Bureau. 2016. “Table DP03, Selected Economic Characteristics.” American Community Survey, 5-Year Estimates Data Profiles. Aspen city, Colorado; 2016. https://data.census.gov/table/ACSDP5Y2016.DP03?q=employment in aspen city&g=160XX00US0803620. U.S. Census Bureau. 2020a. “Table DP03, Selected Economic Characteristics.” American Community Survey, 5-Year Estimates Data Profiles. Aspen city, Colorado; 2020. https://data.census.gov/table/ACSDP5Y2020.DP03?q=employment in aspen city&g=160XX00US0803620. U.S. Census Bureau. 2020b. “Table P1, Race.” Decennial Census, Redistricting Data (PL 94-171). Aspen city, Colorado; 2020. https://data.census.gov/table/ DECENNIALPL2020.P1?q=Aspen city population in 2020&g=160XX00US0803620. U.S. Census Bureau. 2020c. “Table S1901, Income in the Past 12 Months (in 2020 Inflation-adjusted Dollars).” American Community Survey, 5-Year Estimates Subject Tables. Aspen city, Colorado; 2020. https://data.census.gov/table/ ACSST5Y2020.S1901?q=income in aspen city&g=160XX00US0803620. U.S. Census Bureau. 2022a. “Table DP03, Selected Economic Characteristics.” American Community Survey, 5-Year Estimates Data Profiles. Aspen city, Colorado; 2022. https://data.census.gov/table/ACSDP5Y2022.DP03?q=employment in aspen city&g=160XX00US0803620. U.S. Census Bureau. 2022b. “Table DP05, ACS Demographic and Housing Estimates.” American Community Survey, 5-Year Estimates Data Profiles. Aspen city, Colorado; 2022. https://data.census.gov/table/ACSDP5Y2022.DP05?q=Aspen city population in 2022&g=160XX00US0803620. U.S. Census Bureau. 2022c. “Table S1901, Income in the Past 12 Months (in 2022 Inflation-Adjusted Dollars.” American Community Survey, 5-Year Estimates Subject Tables. Aspen city, Colorado; 2022. https://data.census.gov/ table/ACSST5Y2022.S1901?q=income in aspen city&g=160XX00US0803620. U.S. Department of Transportation (DOT). 2023. Benefit-Cost Analysis Guidance for Discretionary Grant Programs. December. https://www.transportation.gov/sites/dot.gov/files/2023-12/Benefit%20Cost% 20Analysis%20Guidance%202024%20Update.pdf. 163 Memorandum: Castle Creek Bridge Economic Impact Analysis 25 Attachment 1: Annual Vehicle Delay Hours During Construction Direction Morning Peak Period[a] Evening Peak Period[a] Off-peak Period[a] Morning Peak Hour[b] Evening Peak Hour[b] Off-peak Hour[b] Weekday Delay Hours Weekend Adjustment Factor Estimated Weekend May 2024 ADT Weekend Delay Hours Delay Hours Per Day (May 2024) Annualization Adjustment Factor Delay Hours Per Day (Annualized) Annual Vehicle Delay Hours Inbound 2,891 1,300 5,146 300 20 20 277 48% 4,524 25 205 132% 270 98,681 Outbound 1,275 2,437 5,783 20 300 20 242 47% 4,503 25 180 132% 238 86,817 Total N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 185,498 ADT = Average Daily Traffic ATR = Automatic Traffic Recorder [a] May 2024 weekday count from ATR [b] Added delay (sec) from July 2024 Vissim model Steps 1 Peak hour delay from VISSIM (July 2024) to apply for the 2.75 hour AM peak and 2.5 hour PM peak period. VISSIM found 149 seconds of AM delay, and negative delay for the PM. Since City of Aspen suggests there will be impact, we assumed 5 minutes of delay in the AM and PM peaks due to the speed reduction. 2 Estimate off-peak delay from off-peak direction in Vissim. 3 Apply delay to May 2024 weekday counts. 4 Use May 2024 weekday versus weekend counts from Colorado Department of Transportation Online Transportation Information System (OTIS) (Location 000236 on State Highway 82, several miles north of study). 5 Estimate average daily delay for May 2024. 6 Use 2022 bridge data by month to convert to annual delay. 164