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HomeMy WebLinkAboutagenda.council.worksession.20160516 CITY COUNCIL WORK SESSION May 16, 2016 5:00 PM, City Council Chambers MEETING AGENDA I. Source Water Protection Plan II. Water Availability Report III. 2016 Water Conservation Report P1 Page 1 of 2 MEMORANDUM TO: Mayor and City Council FROM: Phil Overeynder, Utilities Engineer-Special Projects THRU: Dave Hornbacher, Director Utilities and Environmental Initiatives DATE OF MEMO: May 12, 2016 MEETING DATE: May 16, 2016 RE: Source Water Protection Plan REQUEST OF COUNCIL: Staff requests a Council review of the Source Water Protection Plan. This plan identifies actions which will protect drinking water supply sources (both surface and groundwater) from contamination. PREVIOUS COUNCIL ACTION: The Source Water Protection Program is provided under both federal (Safe Drinking Water Act) and Colorado statutes (Source Water Assessment and Protection) and allows local jurisdictions to identify measures to protect drinking water sources. Previous City Council action on this subject dates to adoption of one of the City’s earliest ordinances “Concerning the Construction and Operation of Waterworks in the Town of Aspen” (October 31, 1885). That ordinance, approved by the voters of Aspen, established the City’s jurisdiction over “streams or sources from which water is taken”. One purpose of the 1885 Ordinance was “protecting such works from injury and the water furnished thereby from pollution.” It further provided authority for the town to establish regulations necessary to protect these water sources. BACKGROUND: Aspen received a grant through the Colorado Department of Public Health and Environment (CDPHE) to prepare the subject plan. The plan was prepared by the Colorado Rural Water Association in consultation with a steering committee. The Steering Committee included Aspen’s water staff members, Pitkin County and the Colorado Division of Mines. Steering Committee members are familiar with conditions that could lead to contamination of the watershed or areas near wells that could cause contamination of supplies. DISCUSSION: The Source Water Protection Plan provides an assessment of both current and potential sources of contamination in the watershed area of both Castle and Maroon Creeks. These two streams serve as the primary drinking water sources. The plan also addresses the three wells operated by Aspen and potential sources of contamination. The susceptibility of water systems to contamination include existing and abandoned mines, wildfire impacts, landslides, P2 I. Page 2 of 2 avalanches and debris flows. The plan also addresses flows into and out of Leonard Thomas Reservoir and provision of security in the vicinity of the water treatment plants. Best Management Practices, strategies and actions are identified for each issue area (contaminant source or other issue) in order to provide continued protection for each of these sources of supply. FINANCIAL/BUDGET IMPACTS: Grant programs have been identified that will assist the City to implement solutions contained in the plan. CITY MANAGER COMMENTS: ATTACHMENTS: Attachment A—Source Water Protection Plan Attachment B—1885 Waterworks Ordinance P3 I. City of Aspen Source Water Protection Plan Pitkin County, Colorado May 2016 Written by: Paul Hempel Source Water Specialist Colorado Rural Water Association For the Community Water Provider: City of Aspen, PWSID# 0149122 P4 I. Cover photo: City of Aspen Maroon Creek Intake by Paul Hempel, CRWA This Source Water Protection Plan for the City of Aspen was developed using the Colorado Rural Water Association’s Source Water Protection Plan Template. P5 I. 1 TABLE OF CONTENTS EXECUTIVE SUMMARY ................................................................................................................................................... 3 INTRODUCTION ............................................................................................................................................................. 5 Purpose of the Source Water Protection Plan .......................................................................................................... 5 Protection Plan Development ................................................................................................................................... 6 Stakeholder Participation in the Planning Process ................................................................................................... 7 Steering Committee .................................................................................................................................................. 7 Development and Implementation Grant ................................................................................................................ 9 WATER SUPPLY SETTING................................................................................................................................................ 9 Location and Description .......................................................................................................................................... 9 Physical Characteristics ........................................................................................................................................... 10 Hydrologic Setting………………………………………………………………………………………………………………………………………. 11 Water Quality Standards ................................................................................................................................... .11 Groundwater Protection .................................................................................................................................... 11 Water Quality Data ............................................................................................................................................ 12 Drinking Water Supply Operations ......................................................................................................................... 13 Water Supply and Infrastructure ....................................................................................................................... 13 Water Supply Demand Analysis ......................................................................................................................... 16 OVERVIEW OF COLORADO’S SWAP PROGRAM ........................................................................................................... 17 Source Water Assessment Phase ............................................................................................................................ 18 Source Water Protection Phase .............................................................................................................................. 19 SOURCE WATER PROTECTION PLAN DEVELOPMENT .................................................................................................. 19 Source Water Assessment Report Review .............................................................................................................. 19 Defining the Source Water Protection Area ........................................................................................................... 20 Potential Contaminant Source Inventory and Other Issues of Concern……………………………………………….…………….24 Priority Strategy ...................................................................................................................................................... 26 Susceptibility Analysis of Water Sources ................................................................................................................ 28 DISCUSSION OF POTENTIAL CONTAMINANT SOURCES AND ISSUES OF CONCERN .................................................... 30 SOURCE WATER PROTECTION MEASURES .................................................................................................................. 44 Best Management Practices ................................................................................................................................... 44 Evaluating Effectiveness of Best Management Practices ....................................................................................... 45 TABLES AND FIGURES…................................................................................................................................................48 REFERENCES………………………………………………………………………………………………………………………………………………………..…49 APPENDICES…………………………………………………………………………………………………………………………..…………………………..….52 P6 I. 2 ACRONYMS BLM Bureau of Land Management BMP Best Management Practice CDOT Colorado Department of Transportation CSFS Colorado State Forest Service CDPHE Colorado Department of Public Health and Environment COGCC Colorado Oil and Gas Conservation Commission CRWA Colorado Rural Water Association EPA Environmental Protection Agency GIS Geographic Information System NRCS Natural Resources Conservation Service PSOC Potential Source of Contamination SDWA Safe Drinking Water Act SWAA Source Water Assessment Area SWAP Source Water Assessment and Protection SWPA Source Water Protection Area SWPP Source Water Protection Plan TOT Time of Travel USDA United States Department of Agriculture USFS United States Forest Service WFSI Wildfire Susceptibility Index WUI Wildland-Urban-Interface P7 I. 3 EXECUTIVE SUMMARY There is a growing effort in Colorado to protect community drinking water sources from potential contamination. Many communities are taking a proactive approach to preventing the pollution of their drinking water sources by developing a source water protection plan. A source water protection plan identifies a source water protection area, lists potential contaminant sources and outlines best management practices to implement to decrease risks to the water source. Implementation of a source water protection plan provides an additional layer of protection at the local level beyond drinking water regulations. The City of Aspen values a clean, high quality drinking water supply and decided to work collaboratively with area stakeholders to develop a Source Water Protection Plan. The source water protection planning effort consisted of public planning meetings and individual meetings with water operators, government, and agency representatives during the months of August, 2012 to March, 2015, at Aspen City Hall. During the development of this Plan, a Steering Committee was formed to develop and implement this Source Water Protection Plan. Colorado Rural Water Association was instrumental in this effort by providing technical assistance in the development of this Source Water Protection Plan. The City of Aspen obtains its drinking water from two surface water intakes on Castle and Maroon Creeks, and potentially from three groundwater wells in the Roaring Fork aquifer. The Source Water Protection Areas for these water sources are upstream to watershed boundary for the surface water intakes and the downtown core for the groundwater intakes. These Source Water Protection Areas are the areas in which the City of Aspen has chosen to focus its source water protection measures to reduce source water susceptibility to contamination. The Steering Committee conducted an inventory of potential contaminant sources and identified other issues of concern within the Source Water Protection Area. Through this process, it was determined that the highest priority potential contaminant sources and/or issues of concern for the Castle and Maroon Creek intakes are existing and abandoned mine sites, wildfire, security, and floods. The highest priority potential contaminant sources and/or issues of concern for the groundwater wells are existing and abandoned mine tunnels. The highest priority potential contaminant sources and/or issues of concern for Leonard Thomas Reservoir are wildfire, landslides/avalanche debris flow, and adequate emergency inflow and outflow control. Other noted water quality threats include sanding of roads (Castle and Maroon Creeks), residential practices and restaurants (groundwater wells) and airborne contaminants introduced during fire suppression (Leonard Thomas Reservoir). The Steering Committee developed several best management practices that may help reduce the risks from the potential contaminant sources and other issues of concern. The best management practices are centered on the themes of building partnerships with community members, businesses, and local decision makers; raising awareness of the value of protecting P8 I. 4 community drinking water supplies; and empowering local communities to become stewards of their drinking water supplies by taking actions to protect their water sources. The following list highlights best management practices which pertain to the highest priority potential contaminant sources and other issues of concern. • Castle and Maroon Creeks Collaborate with the Colorado Division of Reclamation, Mining and Safety for mine reclamation activities in the Castle Creek watershed utilizing $25,000 worth of grant funding. Specifically, these funds would be used for site investigation, reconnaissance and engineering plans for any identified reclamation effort. Provide fire protection for both intake structures including the potential to clear fuels and modify the structures and evaluate both intakes to determine how best to protect them from any post wildfire debris flow. Maintain existing Supervisor Control & Data Acquisition (SCADA) monitoring and daily site visits to monitor security, install fencing around the surface water intake facilities (upon landowner consultation and approval), install security cameras at both intakes and provide a reliable communication connection at both intakes. Conduct a public education and outreach program to residents above the Castle Creek intake to encourage practices that will protect everyone’s drinking water sources. Identify areas above the Castle Creek intake that are susceptible to vehicles running off the road and request Pitkin County to include these areas when planning for and installing guardrails. Distribute the final source water protection plan to Pitkin County Departments of Environmental Health, Community Development, Office of Emergency Management, and Road and Bridge; City of Aspen Departments of Community Development, Environmental Health, Engineering, Streets, and Asset Management; the Aspen Fire District; the Pitkin County Board of Commissioners; the Aspen City Council; and the USFS. • Groundwater Wells Conduct a public education and outreach program to residents in Aspen’s East End to encourage practices that will protect their drinking water sources. Conduct education and outreach to restaurants highlighting waste disposal best management practices. • Leonard Thomas Reservoir Provide fire protection including the potential to clear fuels and modify structures and continue developing a plan to manage post wildfire debris flow. The Steering Committee recognizes that the usefulness of this Source Water Protection Plan lies in its implementation and will begin to execute these best management practices upon completion of this Plan. P9 I. 5 This Plan is a living document that is meant to be updated to address any changes that will inevitably come. The Steering Committee will review this Plan at a frequency of once every two years or if circumstances change resulting in the development of new water sources and source water protection areas, or if new risks are identified. INTRODUCTION The City of Aspen operates a community water system which supplies drinking water to approximately 19,000 users in the Aspen area, located within Pitkin County, Colorado. The City obtains their drinking water from two surface water intakes in the Castle and Maroon Creek watersheds, and potentially from three wells in the Roaring Fork aquifer. The City of Aspen recognizes the potential for contamination of the source of their drinking water, and realizes that it is necessary to develop a protection plan to prevent the contamination of this valuable resource. Proactive planning and implementing contamination prevention strategies are essential to protect the long-term integrity of their water supply and to limit their costs and risks.1 Table 1: Primary Contact Information for the City of Aspen PWSID PWS Name Name Title Address Phone Website 0149122 City of Aspen David Hornbacher Director of Utilities 130 South Galena St. Aspen, CO 81611 970- 429- 1983 aspenpitkin.com Purpose of the Source Water Protection Plan The Source Water Protection Plan (SWPP) is a tool for the City of Aspen to ensure clean and high quality drinking water sources for current and future generations. This Source Water Protection Plan is designed to: • Create an awareness of the community’s drinking water sources and the potential risks to surface water and/or groundwater quality within the watershed; • Encourage education and voluntary solutions to alleviate pollution risks; • Promote management practices to protect and enhance the drinking water supply; 1 The information contained in this Plan is limited to that available from public records and the City of Aspen at the time that the Plan was written. Other potential contaminant sites or threats to the water supply may exist in the Source Water Protection Area that are not identified in this Plan. Furthermore, identification of a site as a “potential contaminant site” should not be interpreted as one that will necessarily cause contamination of the water supply. P10 I. 6 • Provide for a comprehensive action plan in case of an emergency that threatens or disrupts the community water supply. Developing and implementing source water protection measures at the local level (i.e. county and municipal) will complement existing regulatory protection measures implemented at the state and federal governmental levels by filling protection gaps that can only be addressed at the local level. Protection Plan Development The Colorado Rural Water Association’s (CRWA) Source Water Protection Specialist, Paul Hempel, helped facilitate the source water protection planning process. The goal of the CRWA’s Source Water Protection Program is to assist rural and small communities served by public water systems to reduce or eliminate the potential risks to drinking water supplies through the development of Source Water Protection Plans, and provide assistance for the implementation of prevention measures. The source water protection planning effort consisted of a series of public planning meetings and individual meetings. Information discussed at the meetings helped the City of Aspen develop an understanding of the issues affecting source water protection for the community. The Steering Committee then made recommendations for management approaches to be incorporated into the Source Water Protection Plan. In addition to the planning meetings, data and other information pertaining to Source Water Protection Area was gathered via public documents, internet research, phone calls, emails, and field trips to the protection area. A summary of the meetings is represented below. Table 2: Planning Meetings Date Purpose of Meeting May 8, 2012 Water Provider Meeting – Water providers from City of Glenwood Springs, Town of Carbondale, Town of Basalt, Snowmass WSD, City of Aspen, and Environmental Process Control, a local water operator service company, met to create a vision of source water protection in the Roaring Fork Valley. October 29, 2012 Steering Committee Meeting: Discussion concerning City of Aspen surface water intakes and associated potential sources of contamination from existing and abandoned mines. January 28, 2013 Steering Committee Meeting: Discussion concerning City of Aspen groundwater intakes and associated PSOC’s including downtown restaurants. April 16, 2013 Steering Committee Meeting: Discussion concerning proposed septic system outreach program and City of Aspen groundwater intakes and their relation to abandoned mine shafts and tunnels that run underneath the city. September 9, 2013 Steering Committee Meeting: Tour of Hope Mine and Pitkin Iron Mine Transfer Site. November 19, 2013 Steering Committee Meeting: Tour of Smuggler Mine. February 10, 2014 Steering Committee Meeting: Prioritize Potential Sources of Contamination. P11 I. 7 April 28, 2014 Steering Committee Meeting: Development of Best Management Practices. June 30, 2014 Steering Committee Meeting: Tour of Hope Mine. September 17, 2014 Steering Committee Meeting: Tour of Pitkin Iron Mine. November 17, 2014 Steering Committee Meeting: Development of Best Management Practices. December 16, 2014 Steering Committee Meeting: Strategy for Leonard Thomas Reservoir. January 13, 2015 Steering Committee Meeting: Development of Best Management Practices. February 10, 2015 Steering Committee Meeting: Development of Best Management Practices. March 31, 2015 Steering Committee Meeting: Review Draft Source Water Protection Plan. Stakeholder Participation in the Planning Process Local stakeholder participation is vitally important to the overall success of Colorado’s Source Water Assessment and Protection (SWAP) program. Source water protection was founded on the concept that informed citizens, equipped with fundamental knowledge about their drinking water source and the threats to it, will be the most effective advocates for protecting this valuable resource. Local support and acceptance of the Source Water Protection Plan is more likely where local stakeholders have actively participated in the development of their Protection Plan. The City of Aspen’s source water protection planning process attracted interest and participation from 11 stakeholders including water operators, city, county and state governments, and businesses. During the months of October, 2012 through March, 2015, 14 meetings were held at Aspen City Hall to encourage participation in the planning process. Input from these participants was greatly appreciated. Steering Committee During the development of this Plan, a volunteer Steering Committee was formed from the stakeholder group to develop and implement this Source Water Protection Plan. Specifically, the Steering Committee’s role in the source water protection planning process was to advise the City of Aspen in the identification and prioritization of potential contaminant sources as well as management approaches that can be voluntarily implemented to reduce the risks of potential contamination of the untreated source water. All members attended at least one Steering Committee meeting and contributed to planning efforts from their areas of experience and expertise. Their representation provided diversity and led to a thorough Source Water Protection Plan. The City of Aspen and the Colorado Rural Water Association are very appreciative of the participation and expert input from the following participants. P12 I. 8 Figure 1: Some Steering Committee Members on the tour of Smuggler Mine to see firsthand how the local mines were constructed. Table 3: Stakeholders and Steering Committee Members Stakeholder Title Affiliation Steering Committee Member Mark Feinsinger Water Treatment Operator City of Aspen X Mike Mc Dill Deputy Director of Utilities City of Aspen X Phil Overeynder Utilities Engineer City of Aspen X April Long Storm Water Manager City of Aspen X Hailey Guglielmo Civil Engineer City of Aspen X Bryan Daugherty Environmental Health Specialist Pitkin County Environmental Health X Steve Renner Senior Project Manager Colorado Active Mine Program X Stephanie Mitchell Geologist Colorado Active Mine Program X Allen Sorenson Geologist Colorado Active Mine Program Brad Hardman Citizen Aspen Skiing Company Jim Kirschvink Land Specialist USFS Jay Parker Manager Smuggler Mine Carla Ostberg President CBO, Inc. P13 I. 9 Development and Implementation Grant The City of Aspen has been awarded a $5,000 Development and Implementation Grant from the Colorado Department of Public Health and Environment (CDPHE). This funding is available to public water systems and representative stakeholders committed to developing and implementing a source water protection plan. A one to one financial match (cash or in-kind) is required. The City of Aspen was approved for this grant in June 2012, and it expires on June 30, 2016. 100% of the grant funding will be utilized for implementation of the Source Water Protection Plan. WATER SUPPLY SETTING Location and Description Aspen, CO is a municipality covering an area of 3.5 square miles, and is located in Pitkin County on the western slope of Colorado. Primary access to the City is through Colorado State Highway 82. Aspen has 2903 households, a population of 6658 permanent residents (according to the 2010 US census), and is a resort city. Founded as a mining camp during the Colorado Silver Boom and named because of the abundance of aspen trees in the area, the city boomed during the 1880s, its first decade of existence. That early era ended when the Panic of 1893 led to a collapse in the silver market, and the city began a half-century known as "the quiet years" during which its population steadily declined, reaching a low point of less than a thousand by 1930. Aspen's fortunes reversed in the mid-20th century when neighboring Aspen Mountain was developed into a ski resort, and industrialist Walter Paepcke bought many properties in town and redeveloped them. The majority of Aspen’s source waters lie within municipal, county, public and private lands. Public lands are within the White River National Forest, managed by the Aspen - Sopris Ranger District of the United States Forest Service (USFS). Land use on private land consists of agricultural and rural residential development. P14 I. 10 Figure 2: City of Aspen Location within Colorado Source: Google Maps Physical Characteristics Aspen is located at latitude 390 11’ 32” N, longitude 1060 49’ 28” W. Aspen lies within a mountain valley along the Roaring Fork River. It is surrounded by mountain and wilderness areas on three sides: Red Mountain to the north, Smuggler Mountain to the east, and Aspen Mountain to the south at elevations of 10,335 feet, 10,663 feet and 11,319 feet, respectively. The climate in Aspen is considered semi-arid. Temperatures range is 55 ° Fahrenheit as the average high and 27 ° Fahrenheit as the average low. Combined precipitation (snow and rain) averages 24.8 inches per year. (US Climate Data) In the lower part of the sub-watershed, glacial action during the late Pleistocene Epoch (ending about 11,000 years ago) formed a wide, low-gradient valley. When the glaciers retreated, they left deep deposits of glacial outwash that are important in determining stream and riparian habitat characteristics. The Roaring Fork Glacier extended down to what is now the eastern edge of Aspen. At the terminal end of the retreating glacier, morainal deposits acted as a dam that accumulated a thick deposit of alluvium consisting of glacial outwash and lake and stream sediments to a depth of more than 300 feet. The stream channel developed a highly sinuous pattern due to low gradient and deep deposits of soil. Old meander scars indicate that the stream’s historic shape was highly sinuous and that the stream meandered across the width of the valley. These channel characteristics in combination with native riparian vegetation and beaver activity enabled spring flooding flows to overbank and spread across the riparian zone. P15 I. 11 Wetlands occurred across much of the valley floor, even where the river historically did not meander due to shallow groundwater discharge from adjacent slopes. (Roaring Fork Conservancy, 2008) Hydrologic Setting Castle and Maroon Creeks are the principal sources of drinking water for the City of Aspen. These creeks drain approximately 111 square miles and are part of the Colorado River watershed. The potential secondary sources of drinking water for the City of Aspen (the three City groundwater wells) lie within the Roaring Fork aquifer. The Roaring Fork River drains approximately 1453 square miles and is part of the Colorado River watershed (Hydrologic Unit Code (HUC) 1401004). The headwaters of the Roaring Fork River originate approximately 18 miles southeast of Aspen at Independence Pass. Flows are from high altitude glacial, and snowmelt fed lakes. Water quality in the Roaring Fork Aquifer is generally excellent in its headwaters due to near pristine land and water west to the continental divide. In an October 1994 evaluation of raw water availability, Enartech, Inc. identified that stream flow conditions on Castle Creek and Maroon Creek are typically sufficient to satisfy all City water demands, as well as the demands of other local water users including the CWCB in-stream flow water rights. However, it was estimated that during infrequent dry periods, stream flow may not be great enough to meet City demands, and at the same time maintain desired stream flow conditions. Overall, well field effects on the Roaring Fork River during periods of in-stream flow shortages are relatively minor, and probably average less than 200 acre feet per year. (ENARTECH, Inc., 1996) Water Quality Standards Under the Clean Water Act, every state must adopt water quality standards to protect, maintain and improve the quality of the nation's surface waters. Water quality is protected by the Colorado Water Quality Control Act through a number of state agencies. The CDPHE is the lead agency in Colorado. The State of Colorado’s Water Quality Control Commission has established water quality standards that define the goals and limits for all waters within their jurisdictions. Colorado streams are divided into individual stream segments for classification and standards identification purposes (Table 4). Standards are designed to protect the associated classified uses of the streams (Designated Use). Groundwater Protection Groundwater protection is managed as two separate issues of quantity and quality in Colorado. Quantity issues are managed through the Colorado Division of Water Resources/Office of the State Engineer. The Division of Water Resources administers and enforces all surface and groundwater rights throughout the State of Colorado, issues water well permits, approves P16 I. 12 construction and repair of dams, and enforces interstate compacts. The Division of Water Resources is also the agency responsible for implementing and enforcing the statutes of the Groundwater Management Act passed by the Legislature as well as implementing applicable rules and policies adopted by the Colorado Groundwater Commission and the State Board of Examiners of Water Well Construction and Pump Installation Contractors. The Colorado Water Quality Control Commission is responsible for promulgating groundwater and surface water classifications and standards. Colorado's Water Quality Control Commission has established basic standards for groundwater regulations that apply a framework for groundwater classifications and water quality standards for all waters within their jurisdictions. Standards are designed to protect the associated classified uses of water or a designated use. The groundwater classifications are applied to groundwater within a specified area based upon use, quality and other information as indicated in the CDPHE Water Quality Control Commission’s Regulation No. 41, "The Basic Standards for Ground Water.” Statewide standards have been adopted for organic chemicals and radionuclides. Significant areas of the state have been classified for site specific use classification and the remainder of the state's groundwater is protected by interim narrative standards. Classifications and standards are implemented by seven separate state agencies through their rules and regulations for activities that they regulate. Regulated activities include mining and reclamation, oil and gas production, petroleum storage tanks, agriculture, Superfund sites, hazardous waste generation and disposal, solid waste disposal, industrial and domestic wastewater discharges, well construction and pump installation, and water transfers. Colorado has proactive groundwater protection programs that include monitoring groundwater for agricultural chemicals and pesticides, issuing groundwater discharge permits; voluntary cleanup program, permitting for large hog farm operations, and educational programs. In addition, water wells must have a permit and meet minimum standards of construction and pump installation. The City of Aspen could consider petitioning the Water Quality Control Commission for the establishment of a classified ground water area and associated site-specific ground water quality standards for its ground water intakes. Water Quality Data Water quality data for the Roaring Fork River and its tributaries, including Castle and Maroon Creeks, has been collected by multiple entities including the United States Geological Survey (USGS), CDPHE, and Roaring Fork Conservancy (RFC). The Colorado Data Sharing Network offers pertinent water quality data via their website and RFC has generated water quality summary reports for the Roaring Fork watershed, also available on their website. Links to these websites are as follows: http://www.coloradowaterdata.org/ http://www.roaringfork.org/ P17 I. 13 Water Quality Data collected by the CDPHE and RFC was used to determine if these segments meet the stream standards for their designated uses (Regulation 38: Rule Making Hearing, June 2009). Stream segments that do not meet their designated uses are placed on the 303(d) or Monitoring and Evaluation List for Impaired Waters (Regulation 93: Rule Making Hearing, March 2012). Both Castle and Maroon Creeks have no impairments and therefore are not listed. Figure 3: Castle Creek and Maroon Creek Watershed Areas Source: CRWA Drinking Water Supply Operations Water Supply and Infrastructure Castle and Maroon Creeks are the principal sources of drinking water for the City of Aspen. The Creeks drain approximately 111 square miles and are part of the Roaring Fork River watershed (Hydrologic Unit Code (HUC) 1401004). Drinking water from both Creeks is diverted and stored at the Leonard Thomas Reservoir for primary settling prior to treatment. Flows are from high altitude lakes. In addition to the surface water intakes, Aspen has the potential to obtain drinking water from three wells drilled into the Roaring Fork Aquifer. The Roaring Fork Aquifer is a shallow unconfined aquifer consisting of alluvial sediments. Historically, water yields from the Roaring Fork Aquifer range from 600 gallons to 900 gallons per minute. The recharge area for the City of Aspen groundwater wells extends five miles to the east up the Roaring Fork Valley and is P18 I. 14 influenced from precipitation of rain and snow. Typical groundwater flows in the Roaring Fork Aquifer at Aspen are in a northwest direction. These three wells, the Little Nell, Mill Street and Rio Grande, lie within the Roaring Fork alluvium and are 125.5, 111.8 and 92 feet deep respectively. Also, the wells can draw up to 1,296,000, 849,600 and 864,000 gallons of water per day (gal/day) respectively. Water from all three wells would need to be treated before it could be used for a potable water supply in emergency situations. Table 4: Groundwater Supply Information Water System Facility Name Water System Facility Number Total Depth of Well (ft) Depth of Plain Casing (ft) Depth of Perfo- ration (ft) Yield (gpm) Year Drilled Permit No. Annual Permitted Amount (acre feet) Little Nell Well 006 125.5 125.5 125.5 900 1987 2497- RF 2409 Mill Street 008 111.8 101.8 120 590 2002 2792- FR 1613 Rio Grande Well 010 92 92 92 600 2004 62175- F 1614 Table 5: Surface Water Supply Information Water System Facility Name Water System Facility Number Surface Water Source Appropriation Date Appropriation Amount (af/yr) Maroon Creek 005 Maroon Creek 8/12/1892 19,521 Castle Creek 004 Castle Creek 6/25/1892 118,360 Leonard Thomas Reservoir 007 Maroon and Castle Creeks NA NA P19 I. 15 Figure 4: Castle Creek Intake Source: CRWA Figure 5: Maroon Creek Intake Source: CRWA P20 I. 16 Figure 6: Water System Process Schematic Source: City of Aspen (dashed lines indicate that additional treatment may be needed) Water Supply Demand Analysis The City of Aspen serves an estimated 3500 connections and, because Aspen is a resort city, the user group varies daily between 10,000 and 100,000 users. The water system currently has the capacity to produce 20 million gallons of water per day. Current estimates by the water system indicate that the average daily demand is approximately 3 million gallons per day, and that the average peak daily demand is approximately 5 million gallons per day. Using these estimates, the water system has a surplus average daily demand capacity of 17 million gallons per day and a surplus average peak daily demand capacity of 15 million gallons per day. Using the surplus estimates above, the City of Aspen has evaluated its ability to meet the average daily demand and the average peak daily demand of its customers in the event the water supply from one or both of its surface water sources becomes disabled for an extended period of time due to potential contamination. The evaluation indicated the City of Aspen may find it difficult to meet the average daily demand of its customers if the two surface water sources became disabled for an extended period of time. The ability of the City of Aspen to meet daily demands for an extended period of time is also affected by the amount of treated water the water system has in storage at the time a water source(s) becomes disabled. The City of Aspen recognizes potential contamination of its ground water source(s) could possibly result in having to treat the ground water and/or abandon the water source if treatment proves to be ineffective or too costly. P21 I. 17 The potential financial and water supply risks related to the long-term disablement due to contamination of one or both of the community’s surface water sources were a concern of the Steering Committee. As a result, the Steering Committee believed the development and implementation of a source water protection plan for the City of Aspen and the greater Aspen community would help to reduce the risks posed by potential contamination of its water source(s). Additionally, the City of Aspen has developed an Emergency Response Plan (Appendix B) to coordinate rapid and effective response to any emergency incident that threatens or disrupts the community water supply. OVERVIEW OF COLORADO’S SWAP PROGRAM Source water assessment and protection came into existence in 1996 as a result of Congressional reauthorization and amendment of the Safe Drinking Water Act. The 1996 amendments required each state to develop a source water assessment and protection (SWAP) program. The Water Quality Control Division, an agency of the Colorado Department of Public Health and Environment (CDPHE), assumed the responsibility of developing Colorado’s SWAP program. The SWAP program was integrated with the Colorado Wellhead Protection Program that was established in amendments made to the federal Safe Drinking Water Act (SDWA, Section 1428) in 1986. Colorado’s SWAP program is an iterative, two-phased process designed to assist public water systems in preventing potential contamination of their untreated drinking water supplies. The two phases include the Assessment Phase and the Protection Phase as depicted in the upper and lower portions of Figure 7, respectively. P22 I. 18 Figure 7: Source Water Assessment and Protection Phases Source Water Assessment Phase The Assessment Phase for all public water systems consists of four primary elements: 1. Delineating the source water assessment area for each of the drinking water sources; 2. Conducting a contaminant source inventory to identify potential sources of contamination within each of the source water assessment areas; 3. Conducting a susceptibility analysis to determine the potential susceptibility of each public drinking water source to the different sources of contamination; 4. Reporting the results of the source water assessment to the public water systems and the general public. The Assessment Phase involves understanding where the City of Aspen’s source water comes from, what contaminant sources potentially threaten the water sources, and how susceptible each water source is to potential contamination. The susceptibility of an individual water source is analyzed by examining the properties of its physical setting and potential contaminant source threats. The resulting analysis calculations are used to report an estimate of how susceptible each water source is to potential contamination. A Source Water Assessment P23 I. 19 Report was provided to each public water system in Colorado in 2004 that outlines the results of this Assessment Phase. Source Water Protection Phase The Protection Phase is a voluntary, ongoing process in which all public water systems have been encouraged to voluntarily employ preventative measures to protect their water supply from the potential sources of contamination to which it may be most susceptible. The Protection Phase can be used to take action to avoid unnecessary treatment or replacement costs associated with potential contamination of the untreated water supply. Source water protection begins when local decision-makers use the source water assessment results and other pertinent information as a starting point to develop a protection plan. As depicted in the lower portion of Figure 7, the source water protection phase for all public water systems consists of four primary elements: 1. Involving local stakeholders in the planning process; 2. Developing a comprehensive protection plan for all of their drinking water sources; 3. Implementing the protection plan on a continuous basis to reduce the risk of potential contamination of the drinking water sources; and 4. Monitoring the effectiveness of the protection plan and updating it accordingly as future assessment results indicate. The water system and the community recognize that the Safe Drinking Water Act grants no statutory authority to the Colorado Department of Public Health and Environment or to any other state or federal agency to force the adoption or implementation of source water protection measures. This authority rests solely with local communities and local governments. The source water protection phase is an ongoing process as indicated in Figure 7. The evolution of the SWAP program is to incorporate any new assessment information provided by the public water supply systems and update the protection plan accordingly. SOURCE WATER PROTECTION PLAN DEVELOPMENT Source Water Assessment Report Review The City of Aspen has reviewed the Source Water Assessment Report along with the Steering Committee. These Assessment results were used as a starting point to guide the development of appropriate management approaches to protect the source waters of the City of Aspen from potential contamination. A copy of the Source Water Assessment Report for the City of Aspen can be obtained by contacting the City of Aspen or by downloading a copy from the CDPHE’s SWAP program website located at: https://www.colorado.gov/pacific/cdphe/source-water- assessment-and-protection-swap P24 I. 20 Defining the Source Water Protection Area A source water protection area is the surface and subsurface areas from which contaminants are reasonably likely to reach a water source. The purpose of delineating a source water protection area is to determine the recharge area that supplies water to a public water source. Delineation is the process used to identify and map the area around a pumping well that supplies water to the well or spring, or to identify and map the drainage basin that supplies water to a surface water intake. The size and shape of the area depends on the characteristics of the aquifer and the well, or the watershed. The source water assessment area that was delineated as part of the City of Aspen’s Source Water Assessment Report provides the basis for understanding where the community’s source water and potential contaminant threats originate, and where the community has chosen to implement its source water protection measures in an attempt to manage the susceptibility of their source water to potential contamination. After carefully reviewing their Source Water Assessment Report and the CDPHE’s delineation of the Source Water Assessment Area for each of the City of Aspen’s sources, the Steering Committee chose to modify it before accepting it as their Source Water Protection Areas for this Source Water Protection Plan. The Source Water Protection Area was created from the original source water assessment area based on the local issues of concern, conducting an onsite survey of land uses, immediacy of the potential contamination sources to the source water, the type of potential contaminants, and topographic mapping. The City of Aspen’s Source Water Protection Areas are defined as: Little Nell, Mill Street and Rio Grande Wells within city limits Zone 1 represents a 500 foot radius around the wells. Zone 2 represents the perimeter of the downtown business district Maroon and Castle Creek drainages Zone 1 is defined as a 1,000 foot wide band on either side of the Creeks. Zone 2 represents the watershed boundary for the Creeks. Leonard Thomas Reservoir Zone 1 represents a 500 foot radius around the mid-point of the reservoir. Zone 2 represents a 1000 foot radius around the mid-point of the reservoir. The Source Water Protection Areas are illustrated in the following maps. P25 I. 21 Figure 8: City of Aspen Groundwater Wells Source Water Protection Areas Source: CRWA P26 I. 22 Figure 9: Castle and Maroon Creeks Source Water Protection Areas Source: CRWA P27 I. 23 Figure 10: Leonard Thomas Reservoir Source Water Protection Areas Source: CRWA P28 I. Potential Contaminant Source Inventory and Other Issues of Concern Many types of land uses have the potential to contaminate source waters: spills from tanks, trucks, and railcars; leaks from buried containers; failed septic systems, buried or injection of wastes underground, use of fertilizers, pesticides, and herbicides, road salting, as well as urban and agricultural runoff. While catastrophic contaminant spills or releases can wipe out a water resource, groundwater degradation can result from a plethora of small releases o substances. According to the USEPA, nonpoint or into the ground picking up pollutants and carrying them into surface and groundwater) is the leading cause of water quality degradation (GWPC, 2008). Figure 11: Schematic drawing of the potential source of contamination to surface and groundwater In 2001 – 2002, as part of the Source Water Assessment Report, a contaminant source inventory was conducted by the Colorado Department of Public Health and identify selected potential sources of contamination that might be present within the source water assessment areas. Discrete and federal regulatory databases including: mining and reclamation, oil and gas production, above and underground petroleum tanks, Superfund sites, hazardous waste generators, solid waste disposal, industrial and domestic wastewater dischargers, and water well permits. Dispersed contaminant sources were inventoried using then recent land use / land cover and transportation maps of Colorado, along with selected state regulatory databases. The contaminant inventory was completed by mapping the potential contaminant sources with the aid of a Geographic Information System (GIS). The State’s contaminant source inventory consisted of draft maps, along with a summary of the discrete and dispersed contaminant sources inventoried within the source water assessment 2 The WQCD’s assessment process used the terms “discrete” and “dispersed” potential sources of contamination. A discrete source that can be mapped as a point, while a dispersed source covers a broader area such as a type of 24 Source Inventory and Other Issues of Concern Many types of land uses have the potential to contaminate source waters: spills from tanks, trucks, and railcars; leaks from buried containers; failed septic systems, buried or injection of use of fertilizers, pesticides, and herbicides, road salting, as well as urban and agricultural runoff. While catastrophic contaminant spills or releases can wipe out a water resource, groundwater degradation can result from a plethora of small releases o substances. According to the USEPA, nonpoint-source pollution (when water runoff moves over or into the ground picking up pollutants and carrying them into surface and groundwater) is the leading cause of water quality degradation (GWPC, 2008). : Schematic drawing of the potential source of contamination to surface and 2002, as part of the Source Water Assessment Report, a contaminant source inventory was conducted by the Colorado Department of Public Health and Environment to identify selected potential sources of contamination that might be present within the source water assessment areas. Discrete2 contaminant sources were inventoried using selected state and federal regulatory databases including: mining and reclamation, oil and gas production, above and underground petroleum tanks, Superfund sites, hazardous waste generators, solid industrial and domestic wastewater dischargers, and water well permits. Dispersed contaminant sources were inventoried using then recent land use / land cover and transportation maps of Colorado, along with selected state regulatory databases. The minant inventory was completed by mapping the potential contaminant sources with the aid of a Geographic Information System (GIS). The State’s contaminant source inventory consisted of draft maps, along with a summary of the discrete and dispersed contaminant sources inventoried within the source water assessment The WQCD’s assessment process used the terms “discrete” and “dispersed” potential sources of contamination. A discrete source that can be mapped as a point, while a dispersed source covers a broader area such as a type of land use (crop land, forest, residential, etc.). Many types of land uses have the potential to contaminate source waters: spills from tanks, trucks, and railcars; leaks from buried containers; failed septic systems, buried or injection of use of fertilizers, pesticides, and herbicides, road salting, as well as urban and agricultural runoff. While catastrophic contaminant spills or releases can wipe out a water resource, groundwater degradation can result from a plethora of small releases of harmful source pollution (when water runoff moves over or into the ground picking up pollutants and carrying them into surface and groundwater) is the : Schematic drawing of the potential source of contamination to surface and 2002, as part of the Source Water Assessment Report, a contaminant source Environment to identify selected potential sources of contamination that might be present within the source contaminant sources were inventoried using selected state and federal regulatory databases including: mining and reclamation, oil and gas production, above and underground petroleum tanks, Superfund sites, hazardous waste generators, solid industrial and domestic wastewater dischargers, and water well permits. Dispersed contaminant sources were inventoried using then recent land use / land cover and transportation maps of Colorado, along with selected state regulatory databases. The minant inventory was completed by mapping the potential contaminant sources with the The State’s contaminant source inventory consisted of draft maps, along with a summary of the discrete and dispersed contaminant sources inventoried within the source water assessment The WQCD’s assessment process used the terms “discrete” and “dispersed” potential sources of contamination. A discrete source is a facility land use (crop land, forest, residential, etc.). P29 I. 25 area. The City of Aspen was asked, by CDPHE, to review the inventory information, field-verify selected information about existing and new contaminant sources, and provide feedback on the accuracy of the inventory. Through this Source Water Protection Plan, the City of Aspen will report its findings to the CDPHE. After much consideration, discussion, and input from local stakeholders, the City of Aspen and the Steering Committee have developed a more accurate and current inventory of contaminant sources located within the Source Water Protection Area. Upon completion of this contaminant source inventory, the City of Aspen has decided to adopt it in place of the original contaminant source inventory provided by the CDPHE. Maroon and Castle Creeks Contaminant Source Inventory (in no particular order): • Roads/Vehicles • Roads/Sanding • Existing Abandoned Mine Sites • Residential Practices Maroon and Castle Creeks Additional Issues of Concern (in no particular order): • Wildfire • Plane Crashes • Floods/Landslides/Avalanche Debris Flow • Security Little Nell, Mill Street and Rio Grande Wells Contaminant Source Inventory (in no particular order): • Storm Water Runoff • Existing Abandoned Mine Sites • Residential Practices • Roads/Vehicles • Roads/Sanding • Small Quantity Hazardous Waste Generators (see below businesses): - Restaurants Little Nell, Mill Street and Rio Grande Wells Additional Issues of Concern • Increase in fluoride and radio nuclide contaminant levels Leonard Thomas Reservoir Contaminant Source Inventory (in no particular order): • Wildfire • Site Access Road Inside Fence at Plant • Wildlife P30 I. 26 Leonard Thomas Reservoir Additional Issues of Concern (in no particular order): • Floods/Landslides/Avalanche Debris Flow • Ability to Manage Emergency Flows into and out of the Reservoir • Airborne Contaminants (fire retardant) • Pesticides and Herbicides Priority Strategy After developing a contaminant source inventory and list of issues of concern that is more accurate, complete, and current, the Steering Committee began the task of prioritizing this inventory for the implementation of the Best Management Practices outlined in this Source Water Protection Plan. The following was considered by the Steering Committee when devising this strategy: 1. Migration Potential or Proximity to the Water Source - The migration potential generally has the greatest influence on whether a contaminant source could provide contaminants in amounts sufficient for the source water to become contaminated at concentrations that may pose a health concern to consumers of the water. Shorter migration paths and times of travel mean less chance for dilution or degradation of the contaminant before it reaches water sources. The proximity of potential sources of contamination to the City of Aspen water sources was considered relative to the two sensitivity zones in the Source Water Protection Area (i.e. Zone 1 and Zone 2). 2. Contaminant Hazard - The contaminant hazard is an indication of the potential human health danger posed by contaminants likely or known to be present at the contaminant source. Using the information tables provided by CDPHE (see Appendices E-H), the Steering Committee considered the following contaminant hazard concerns for each contaminant source: • Acute Health Concerns - Contaminants with acute health concerns include individual contaminants and categories of constituents that pose the most serious immediate health concerns resulting from short-term exposure to the constituent. Many of these acute health concern contaminants are classified as potential cancer-causing (i.e. carcinogenic) constituents or have a maximum contaminant level goal (MCLG) set at zero (0). • Chronic Health Concerns - Contaminants with chronic health concerns include categories of constituents that pose potentially serious health concerns due to long-term exposure to the constituent. Most of these chronic health concern contaminants include the remaining primary drinking water contaminants. • Aesthetic Concerns - Aesthetic contaminants include the secondary drinking water contaminants, which do not pose serious health concerns, but cause P31 I. 27 aesthetic problems such as odor, taste, turbidity, or appearance. 3. Potential Volume - The volume of contaminants at the contaminant source is important in evaluating whether the source water could become contaminated at concentrations that may pose a health concern to consumers of the water in the event these contaminants are released to the source water. Large volumes of contaminants at a specific location pose a greater threat than small volumes. 4. Likelihood of Release - The more likely that a potential source of contamination is to release contaminants, the greater the contaminant threat posed. The regulatory compliance history for regulated facilities and operational practices for handling, storage, and use of contaminants were utilized to evaluate the likelihood of release. The Steering Committee then utilized Table 6 as a method to further rank their potential sources of contamination. Table 6: Priority Strategy for Castle and Maroon Creeks Issue/Contaminant/Threats In Our Control? Impact (H, M, L) Probability (H, M, L) Total Factor (H, M, L) Priority for Focus Existing/Abandoned Mine Sites Yes - indirect H M H 1 Wildfire Yes - indirect H M H 1 Security No H L M 1 Roads - vehicles No H L L 2 Roads - sanding Yes - indirect M M M 2 Floods No H H H 1 Landslide/Avalanche Debris Flow No H M M 2 Residential Practices Yes - indirect L L L 3 Plane Crashes No H L L 3 Table 7: Priority Strategy for Groundwater Wells Issue/Contaminant/Threats In Our Control? Impact (H, M, L) Probability (H, M, L) Total Factor (H, M, L) Priority for Focus Existing/Abandoned Mine Sites Yes – indirect H M H 1 Storm Water Runoff Yes – indirect M L L 2 Residential Practices Yes – indirect M L L 2 Restaurants Yes M L L 2 Roads - vehicles Yes – indirect L M L 3 Roads - sanding Yes – indirect L M L 3 P32 I. 28 Table 8: Priority Strategy for Leonard Thomas Reservoir Issue/Contaminant/Threats In Our Control? Impact (H, M, L) Probability (H, M, L) Total Factor (H, M, L) Priority for Focus Wildfire No H M H 1 Road Inside Fence at Plant Yes H L L 2 Wildlife Yes L L L 3 Landslides/Avalanche Debris Flow No H M H 1 Ability to Manage Emergency Flows into and out of the Reservoir Yes H H H 1 Airborne Contaminants (fire retardant) No H L M 2 Pesticides/Herbicides Yes M L L 3 Based on the above criteria and calculations from Tables 7, 8 and 9, the Steering Committee has ranked the potential contaminant source inventory and issues of concern in the following way: Prioritized Potential Contaminant Sources and Issues of Concern (# 1 Priority ranking) Castle and Maroon Creeks • Existing/Abandoned Mine Sites • Wildfire • Security • Floods Groundwater Intakes • Existing/Abandoned Mine Sites Leonard Thomas Reservoir • Wildfire • Landslides/Avalanche Debris Flow • Ability to Manage Emergency Flows into and out of the Reservoir Susceptibility Analysis of Water Sources The City of Aspen’s Source Water Assessment Report contained a susceptibility analysis3 to identify how susceptible an untreated water source could be to contamination from potential sources of contamination inventoried within its source water assessment area. The analysis looked at the susceptibility posed by individual potential contaminant sources and the collective or total susceptibility posed by all of the potential contaminant sources in the source 3 The susceptibility analysis provides a screening level evaluation of the likelihood that a potential contamination problem could occur rather than an indication that a potential contamination problem has or will occur. The analysis is NOT a reflection of the current quality of the untreated source water, nor is it a reflection of the quality of the treated drinking water that is supplied to the public. P33 I. 29 water assessment area. The CDPHE developed a susceptibility analysis model for surface water sources and ground water sources under the influence of surface water, and another model for groundwater sources. Both models provided an objective analysis based on the best available information at the time of the analysis. The two main components of the CDPHE’s susceptibility analysis are: 1. Physical Setting Vulnerability Rating – This rating is based on the ability of the surface water and/or groundwater flow to provide a sufficient buffering capacity to mitigate potential contaminant concentrations in the water source. 2. Total Susceptibility Rating – This rating is based on two components: the physical setting vulnerability of the water source and the contaminant threat. Upon review of the susceptibility analysis, the Steering Committee determined that the Physical Setting Vulnerability Rating and the Total Susceptibility Rating needed updated to more accurately reflect the current situation. Table 9: Updated Susceptibility Analysis [#8-Paul, what do the two “?” in column one indicate?] Source ID # Source Name Source Type Total Susceptibility Rating Physical Setting Vulnerability Rating 149122- 006 Little Nell Well Groundwater Low Moderately Low 149122- 00? Mill Street Well Groundwater Low Low 149122- 00? Rio Grande Well Groundwater Low Low 149122- 005 Maroon Creek Surface Water Moderately High Moderate 149122- 004 Castle Creek Surface Water Moderately High Moderate 149122- 005 Leonard Thomas Reservoir Surface Water Moderate Moderately Low P34 I. 30 DISCUSSION OF POTENTIAL CONTAMINANT SOURCES AND ISSUES OF CONCERN 1. Existing/Abandoned Mines The Aspen area was originally discovered by the Ute Indians and called "Shining Mountains". The first silver miners arrived in the Roaring Fork Valley in the summer of 1879 and by that fall a small group of entrepreneurs and speculators had staked claims and set up camp at the foot of Aspen Mountain. Prospectors settled in Aspen hoping to strike it rich in silver. By 1891 Aspen had surpassed Leadville as the nation's largest single silver producing mining district. By 1893, Aspen was a booming silver town with 12,000 people, six newspapers, two railroads, four schools, three banks, electric lights, a modern hospital, two theaters, an opera house, and a very small brothel district. In 1893 however the Sherman Silver Act was repealed which demonetized silver and marked Aspen's decline as a mining town. Ironically, one of the largest nuggets of native silver ever found was mined in 1894 in Aspen from the Smuggler mine, weighing in at 2,350 pounds. After the silver bust in the early 1900s as few as 700 people remained in Aspen during what is known as the “quiet years.” (aspenpitkin.com) Thousands of unpatented claims and small exploratory mining operations throughout Colorado exist, most of which were never recorded in state or local government offices. It was not until 1973 that the State of Colorado required mines to be permitted. Current mining permit data for the source water protection areas can be obtained from the Colorado Division of Reclamation, Mining and Safety. Mining practices during the early days allowed the mine owners to simply abandon their mines without consideration of the impact on streams, water quality, slope stability and safety. Many old mining properties contain abandoned mine workings, mine waste and/or mill tailings. Active and inactive mining operations have a potential to contaminate drinking water supplies from either point source discharges (i.e. mine drainage tunnels or flowing adits) or nonpoint source discharges from run-off over waste rock or tailing piles. Acidic, metal-laden water emanating from inactive mines and waste rock piles has a potential to impair aquatic life in the Roaring Fork River upstream from the Cities drinking water intakes. (Williams, 2013) In respect to existing/abandoned mines, the Pitkin Iron Mine was the main focus for the City of Aspen in the development of this source water protection plan. Discovered in the early 1880’s, the Pitkin Iron Mine lays above an unnamed tributary of the Cooper Fork, a tributary to Castle Creek. During this time period production at the mine was minimal yet it was reported at the time that the mine had a reserve of up to 3 to 4 million tons of ore. Although iron was the primary mineral extracted here, titanium, manganese, copper and silver was also recovered. The deposit lay at contact between Leadville Limestone and Weber Sandstone metamorphosed by local Granodiorite or Diorite intrusions. More recent activity at the mine began after 1960 by CF & I Steel Corporation. This newer development utilized a P35 I. 31 quarry-type open pit mining approach utilizing 150 X 75 X 30 foot benches. (westernmininghistory.com) The Pitkin Iron Mine was permitted in 1978 and operated until the mid-1990. In the fall of 1995, the Division of Reclamation, Mining and Safety responded to a permit release request and released the Operator from further reclamation responsibilities. The mine permit was then terminated. In the fall of 2013 and 2014, the City of Aspen Source Water Protection Steering Committee visited the quarry area and 37 acre permit area. The main area of concern for the Steering Committee is the mill site drainage ditch that runs from the southern portion of the permit area to the north. This drainage could be further investigated for erosion control and metals mobilization. Other concerns were the open quarry type feature that could pose a safety issue and the lack of vegetation within the area. The Division of Reclamation, Mining and Safety has made $25,000 available to the City of Aspen, upon application, for further site investigations and engineering plans for reclamation efforts. Because the site was permitted and then released by the Division of Reclamation, Mining and Safety, the funding is limited for reclamation efforts within the previously permitted area. However, this funding can be used for areas outside the permitted area, such as offsite erosion that may be affected by previous mining activity at the Pitkin Iron Mine Site. In the future the City of Aspen will look at how the existing south/north mill site drainage in the permitted area could potentially be of concern for Castle Creek. Figure 12: Pitkin Iron Mine Location Source: CRWA P36 I. 32 Figure 13: Pitkin Iron Mine Mill Site Location Source: CRWA Figure 14: Pitkin Iron Mine Mill Site Drainage System and Permitted Area. Source: Division of Mining Reclamation and Safety P37 I. 33 Figure 15: Pitkin Iron Mine and Mill Site Location in Relation to Castle Creek Figure 16: Pitkin Iron Mine Mill Site Location 2 Source: CRWA P38 I. 34 Figure 17: Pitkin Iron Mine Mill Site Location 3 Source: CRWA Existing/Abandoned Mines Best Management Practices 1. Collaborate with the Colorado Division of Reclamation, Mining and Safety for mine reclamation activities in the Castle Creek watershed utilizing the above referenced $25,000 of grant funding. Specifically, these funds would be used for site investigation, reconnaissance and engineering plans for a reclamation effort. 2. Wildfire Much of the attention paid to wildfire and its impacts on the hydrologic cycle focuses on increased danger from flooding and mudslides during the immediate post-fire period. While threats to human health and safety posed by floods, debris flows, and mudslides certainly cause the greatest concern, water quality impacts and their associated risks are nonetheless critical for water utilities and regulatory agencies to address. Important questions are: 1. What impact does wildfire have on surface water quality? 2. How long does the impact last? 3. How far away from burned areas can water quality impacts be felt? 4. What beneficial uses can be affected by the changes in water quality induced by wildfire? 5. How can adverse impacts of wildfire on water quality be prevented, mitigated, or otherwise minimized? The quality of surface waters can be examined in terms of physical, chemical, and biological characteristics. Here we consider only the impacts of fire on physical and chemical water properties, based on research in the coniferous forests and chaparral watersheds of California. Biological impacts are inferred from the changes in the physical and chemical properties of surface waters. Most impacts on the physical characteristics of fire-impacted streams are evidenced by changes in sediment load. Increased sediment flows following a fire can impact both ecological health and drinking water operations. The large quantities of post-fire sediment can overwhelm the biological habitat available for aquatic organisms such as fish, as well as organisms that depend on water for some life stage, such as amphibians and insects. P39 I. 35 Large post-fire sediment fluxes impact drinking water systems two ways. First and perhaps foremost is the danger that reservoirs, infiltration basins, and treatment works will be filled, damaged, or otherwise disrupted by sediment. Second, high sediment load is likely to increase pre-treatment processing needs (and costs) for suspended sediment removal. These impacts are highest in areas immediately adjacent to fires. (Meixner and Wohlgmuth, 2004) Wildfire and related suppression activities are potential sources for surface water contamination. Sources of contaminants from a burned area may include increased sediment, debris, and ash flows into surface waters. The chemicals used in fire retardants can also be a source of contamination should they migrate through runoff into drinking water supplies. The degree of contamination is controlled by the size of the burned area, distance to surface water, remaining vegetation cover, terrain, soil erosion potential, and subsequent precipitation and intensity (Walsh Environmental, 2012). The potential of a watershed to deliver sediments to surface waters after a wildfire depends on forest and soil conditions, the physical condition of the watersheds, and the sequence and magnitude of rain fall on the burned area. In cases of a high-severity fire, normal runoff and erosion processes can be dramatically altered and magnified. Most of Colorado’s wildfires are caused by lightning strikes from the many thunderstorms that pass through the state on a regular basis during the summer months. Lightning strikes sometimes create hotspots which can spread into full-fledged fires under the right conditions. Backcountry recreational activity involving irresponsible fire safety practices by campers and hikers can also lead to the occurrence of wildfire. Figure 18: Wildfire in Relation to a Community Water System in Colorado. This graphic is not the City of Aspen’s water treatment facility. Source: KMGH Channel 7 P40 I. 36 Figure 19: Buffalo Creek Wildfire Post Wildfire Debris and Mudflow: Jefferson County, CO Source: CRWA Community Wildfire Protection Plan Pitkin County adopted the format of the Colorado State Forest Service’s (CSFS) state-wide Wildfire Hazard Map and the tools used in its development (Geographical Information System based analysis), but has updated this process for this 2009 revision to incorporate new data, information, and GIS tools, and the impacts of mountain pine beetle. These maps take into consideration slope, aspect, fuel types, potential ignition sources, housing density, road density, and lighting strikes. At the County scale, this map is very accurate. At tighter scales these maps are not entirely accurate, and thus Pitkin County supports and is in the process of developing sub-County level CWPPs. As part of the analysis process in determining wildland fire risk and hazards, the CSFS model was utilized, but further enhanced by utilizing the more accurate Pitkin County GIS vegetation data layer. In comparing ReGAP vegetation data, USFS data, and Pitkin County GIS vegetation data, the Pitkin County’s vegetation data was found to be the most accurate of these three GIS data themes, but even still the Pitkin County GIS data had some observed inaccuracies. The data was then ground-truthed and aerial photo interpretation was utilized to further enhance the Pitkin County vegetation data resources to key in on lodge pole pine stands due to mountain pine beetle induce d mortality. From these data the Wildland Fire Hazard Maps were produced. Additional maps were then produced using the Pitkin County vegetation data layers and Pitkin County assessor data as well as lightning strike and road data to produce overall Wildland Fire Hazard (Risk + Hazards + Values) Maps. (PCWFPP, 2014) P41 I. 37 Figure 20: Pitkin County Wildfire Hazards Map Source: Pitkin County Wildland Fire Plan A comprehensive community wildfire assessment takes into account a variety of factors in order to fully identify and assess wildfire risks and hazards. These include the nature of community infrastructure, terrain, proximity of hazardous fuels, and probability of wildfire occurrence. By analyzing these elements, including input from residents and Fire Protection Districts, an understanding of wildfire risks and hazards can be developed that provides guidance for developing effective vegetation-fuel treatments and other mitigation opportunities to improve Fire Protection Districts’ response capabilities. (Walsh Environmental, 2012) Wildfire Best Management Practices 1. Provide fire protection for both the Castle and Maroon Creek intake structures and Leonard Thomas Reservoir including the potential to clear fuels and modify the intake structures. 2. Continue developing a plan for Leonard Thomas Reservoir and evaluate both intake structures to determine how best to protect them from post wildfire debris flow. 3. Distribute the final source water protection plan to the USFS. 3. Floods/Landslides/Avalanche Debris Flow Floods are the most common and widespread of all natural disasters, except fire, according to the Federal Emergency Management Agency. Most communities have experienced some degree of flooding following heavy rain or spring and winter thaws. Floods pose a particular threat to drinking water systems because floodwaters often carry biological and chemical contaminants that can make consumers sick. Contaminants may include bacteria, viruses, protozoa or petroleum products from fuel spills in nearby areas. If source Maroon & Castle Creeks P42 I. 38 water or any part of the water distribution system flood, these contaminants can end up at consumer taps. Increased water flow during a flood often makes rivers and streams murky. Elevated turbidity in source water could make it impossible for a water system’s treatment plant to treat water. If that occurs, the water system may have to rely on emergency storage capacity or an emergency water source. Either way, the water system will have to ask customers to conserve water. That request can confuse customers when flooding or heavy rains make it look like there is water everywhere. Even if the water system can overcome high turbidity, the change in disinfection levels may cause taste or odor problems in the treated water. (Washington State Department of Health, 2010) Debris from floods is caused by structural inundation and high-velocity water flow. As soon as flood waters recede, people begin to dispose of flood-damaged household items. Mud, sediment, sandbags, and other reinforcing materials also add to the volume of debris needing management, as do materials from demolished and dismantled houses. Surface water intakes run the risk of becoming damaged or blocked because of debris flows. While fires leave less debris than other types of disasters, they still generate much waste. For example, demolished houses contribute noncombustible debris. Burned out cars and other metal objects, as well as ash and charred wood waste, also must be managed. In addition, large-scale loss of plants serving as ground cover can lead to mud slides, adding debris to the waste stream. (US EPA) In September, 2013, the Front Range and plains of eastern Colorado suffered through a catastrophic flooding event. The historic flooding impacted more than 24 counties and more than 2,000 square miles. The floods took 10 lives, and forced the evacuation of more than 18,000 residents, while causing an estimated $3 billion in damage, including $1.7 billion to the state’s infrastructure, $623 million to housing and $555 billion to the state’s economy. (State of Colorado) P43 I. 39 Figure 21: Raging flood destroying a bridge along Highway 34 toward Estes Park, Colo. (AP Photo/Colorado Heli-Ops, Dennis Pierce) The City of Aspen recognizes the Maroon and Castle Creek drainages are vulnerable to flooding. Although it is nearly impossible to plan for all of the consequences of a flood and post flood debris flow, it is possible to have a system in place to notify the public in the case of a catastrophic event. Floods/Landslides/Avalanche Debris Flow Best Management Practices 1. Utilize current process to notify the public in case of a catastrophic event. 2. Switch water sources, if necessary, to continue to provide safe clean water to the City of Aspen users. 4. Ability to Manage Flows into and out of the Leonard Thomas Reservoir For debris entering Leonard Thomas Reservoir due to a catastrophic flooding event, a controlled release may be undertaken to prevent unintended overtopping. Previous use of an existing drain line at the reservoir resulted in undesirable erosion as no armored conveyance channel exists in this location. Alternatively, a scenario in which the spillway or a dam breech occurs at the reservoir could result in released water being heavily reliant on the street capacity of the adjacent Doolittle Drive. In a large event, in which existing street capacity is exceeded, released water could potentially extend out of the roadway into adjacent property and structures in some areas. Such actions are regulated by the State of Colorado Department of Natural Resources, Dam Safety Branch Document 2-CCR 402-1, Rules and Regulations of Dam Safety and Dam P44 I. 40 Construction, Section 12.3, Emergency Action, Point 12.3.2. This Section states: “Lowering the reservoir level by aiming controlled releases though the outlet or gated spillway by pumping or by siphoning. Where large releases are to be made the Division Engineer shall be notified.” Flows into and out of the Leonard Thomas Reservoir - Best Management Practices 1. Develop a dredging maintenance schedule to maintain intended storage and freeboard. 2. Evaluate the methods available to deliver all expected flows from Leonard Thomas Reservoir to Castle Creek, or another viable drainage way. 3. Follow CCR 402-1 section 12.3.2 for noticing Division Engineer when large releases may be necessary. 4. Evaluate Leonard Thomas Reservoir breach/overtopping scenario and conveyance systems and strategies, as described in the 2014 Revised Inundation Plan for Leonard Thomas Reservoir Emergency Plan. 5. Security The September 11, 2001, attacks on the World Trade Center and the Pentagon have drawn attention to the security of many institutions, facilities, and systems in the United States, including the nation’s water supply and water quality infrastructure. These systems have long been recognized as being potentially vulnerable to terrorist attacks of various types, including physical disruption, bioterrorism/chemical contamination, and cyber-attack. Damage or destruction by a terrorist attack could disrupt the delivery of vital human services in this country, threatening public health and the environment, or possibly causing loss of life. Further, since most water infrastructure is government-owned, it may serve as a symbolic and political target for some. A successful attack on even a small system could cause widespread panic, economic impacts, and a loss of public confidence in water supply systems. Aspen is a small system with worldwide recognition and when an incident happens to the City’s water supply Aspen often makes international news. Substantial economic impact to the City due to a loss of visitors would occur if such an event were to take place. Both the Maroon and Castle Creek intake structures are vulnerable to vandalism. Understanding that indiscriminate vandalism could endanger the water supply, additional security measures may be warranted. P45 I. 41 Security Best Management Practices 1. Maintain existing Supervisor Control & Data Acquisition (SCADA) monitoring and daily site visits to monitor security. 2. Install fencing around the surface water intake facilities (upon landowner consultation and approval). 3. Install security cameras at both intakes and provide a reliable communication connection. 6. Residential Practices The source water protection area for the Castle and Maroon Creek intakes and the Roaring Fork River Wells includes rural and urban residential land use areas. Common household practices including washing vehicles, lawn fertilization, and pet wastes can allow chemicals and biologic pollutants to runoff residential property and enter the surface or ground water as indicated in Figure 22, below. Prevention of ground and surface water contamination requires education, public involvement, and people motivated to help in the effort. Educating the community and decision-makers is one of the challenges and cornerstone of this protection plan. Public education will help people understand the potential threats to their drinking water sources and motivate them to participate as responsible citizens to protect their valued resources. Figure 22: Residential Practices Source: CSU Extension P46 I. 42 Residential Practices Best Management Practices 1. Conduct a public education and outreach program to residents above the Castle Creek intake and in Aspen’s East End to encourage practices that will protect their drinking water sources. 7. Restaurants Fats, oils and grease (FOG) come from butter, lard, vegetable fats and oils, meats, nuts and cereals. Fats are among the more stable of the organic compounds and are not easily decomposed by bacteria. Improperly managed oil and grease from restaurants is a significant problem for wastewater collection and treatment systems. FOG can coat, congeal and accumulate in pipes, pumps and equipment, leading to the costly and hazardous flow of waste grease into drain lines, sewer lines, lift stations, drain fields and Publicly Owned Treatment Works (POTW’s). Grease blockages can cause back-ups into kitchens or basements, or can lead to sanitary sewer overflows (SSOs) which can cause untreated sewage to flow onto streets and travel to storm drains, creeks, and other surface waters. Improper disposal can result in high biological oxygen demand (BOD) and chemical oxygen demand (COD) levels, increasing costs, and clogged collection systems. Additionally, restaurant employees who dump FOG constituents onto impervious surfaces or directly into storm drains can ultimately cause harm to surface water or groundwater that act as sources of community drinking water supplies. Pumping out a grease trap is considerably more costly than a service fee from a hauler. In addition, with dry clean-up and other source reduction measures, many restaurants can reduce their water consumption and sewer use, which leads to more money saved. Recycling of oils and grease helps to keep the compounds from entering waterways, clogging municipal sewer lines, and taking up valuable space in landfills. (Michigan Department of Environmental Quality) Figure 23: Improper FOG Disposal Source: California Department of Environmental Protection P47 I. 43 There are approximately 100 restaurants in Aspen’s downtown core. The cumulative effects of restaurants improperly disposing of FOG constituents could negatively impact the surface water or groundwater that act as sources of community drinking water. Restaurants Best Management Practices 1. Conduct education and outreach to restaurants highlighting waste disposal best management practices. 8. Roads: Vehicles and Sanding Motor vehicles, roads and parking facilities are a major source of water pollution to both surface and groundwater. An estimated 46% of US vehicles leak hazardous fluids, including crankcase oil, transmission, hydraulic, and brake fluid, and antifreeze, as indicated by oil spots on roads and parking lots, and rainbow sheens of oil in puddles and roadside drainage ditches. An estimated 30-40% of the 1.4 billion gallons of lubricating oils used in automobiles are either burned in the engine or lost in drips and leaks, and another 180 million gallons are disposed of improperly onto the ground or into sewers. Runoff from roads and parking lots has a high concentration of toxic metals, suspended solids, and hydrocarbons, which originate largely from automobiles (Gowler and Sage, 2006). Storm water runoff over these roads can deliver contaminants from the road surface into nearby streams and rivers. Vehicular spills may occur along the transportation route within the source water protection areas from trucks that transport fuels, waste, and other chemicals that have a potential for contaminating the groundwater. Chemicals from accidental spills are often diluted with water, potentially washing the chemicals into the soil and infiltrating into the groundwater. Roadways are also frequently used for illegal dumping of hazardous or other potentially harmful wastes. During the winter season road authorities apply a salt-sand mixture and/or de-icer (magnesium chloride, M1000, or Ice Slicer) to roadways along routes within the source water protection areas. Surface and groundwater quality problems resulting from the use of road de-icers are causing concern among federal, state, and local governments. Salt from the roadway is introduced into surface and groundwater through a number of ways: 1) When runoff occurs from roadways, flows are sometimes carried directly into surface waters, ditches and unlined channels through which the water infiltrates into the soil and eventually into the groundwater. 2) Also, when snow is plowed together with the salt, the pile that is accumulated on the roadside melts during warmer weathers. The water that results contains dissolved salt which can also enter the surface water and infiltrate into groundwater. Plowing and splashing of salt causes the salt to deposit along the pavement, especially near the shoulders where it melts causing runoff to enter drainage ways and then the groundwater system (Seawell, et al, 1998). Maroon Creek and Castle Creek Roads parallel their respectively named waterbodies. Improper road maintenance activities including the over application of sand and salt could have the potential to introduce these constituents into the Creeks and ultimately, the intake structures. P48 I. 44 Further, there are no guardrails along these roadways that could help prevent vehicles from driving off the roads and into the Creeks. Roads: Vehicles and Sanding Best Management Practices 1. Evaluate the need for a Contingency/Emergency Action Plan to address road related accidents, fuel spills and application of road deicing materials. 2. Identify areas above the Castle Creek intake that are susceptible to vehicles running off the road and request Pitkin County to include these areas when planning for and installing guardrails. 3. Distribute the final source water protection plan to Pitkin County Environmental Health, Community Development, Office of Emergency Management and Road and Bridge Departments. SOURCE WATER PROTECTION MEASURES Best Management Practices The Steering Committee reviewed and discussed several possible best management practices that could be implemented within the Source Water Protection Area to help reduce the potential risks of contamination to the community’s source water. The Steering Committee established a “common sense” approach in identifying and selecting the most feasible source water management activities to implement locally. The focus was on selecting those protection measures that are most likely to work for the community. The best management practices were obtained from multiple sources including: Environmental Protection Agency, Colorado Department of Public Health and Environment, Natural Resources Conservation Service, and other source water protection plans. The Steering Committee recommends the best management practices listed in Table 10, “Source Water Protection Best Management Practices” be considered for implementation by: City of Aspen Pitkin County United States Forest Service Colorado Division of Reclamation, Mining and Safety P49 I. 45 Evaluating Effectiveness of Best Management Practices The City of Aspen is committed to developing a tracking and reporting system to gauge the effectiveness of the various source water best management practices that have been implemented. The purpose of tracking and reporting the effectiveness of the source water best management practices is to update water system managers, consumers, and other interested entities on whether or not the intended outcomes of the various source water best management practices are being achieved, and if not, what adjustments to the Source Water Protection Plan will be taken in order to achieve the intended outcomes. CDPHE recommended that this Plan be reviewed at a frequency of once every 3 - 5 years or if circumstances change resulting in the development of new water sources and source water protection areas, or if new risks are identified. The City of Aspen is committed to a mutually beneficial partnership with the Colorado Department of Public Health and Environment in making future refinements to their source water assessment and to revise the Source Water Protection Plan accordingly based on any major refinements. P50 I. 46 Ta b l e 1 0 : S o u r c e W a t e r P r o t e c t i o n B e s t M a n a g e m e n t P ra c t i c e s Is s u e s Be s t M a n a g e m e n t P r a c t i c e s Im p l e m e n t e r s Ex i s t i n g / A b a n d o n e d M i n e Si t e s 1. C o l l a b o r a t e w i t h t h e C o l o r a d o D i v i s i o n o f R e c l a m at i o n , M i n i n g an d S a f e t y f o r m i n e r e c l a m a t i o n a c t i v i t i e s i n t h e C as t l e C r e e k wa t e r s h e d u t i l i z i n g $ 2 5 , 0 0 0 w o r t h o f g r a n t f u n d i n g . S p e c i f i c a l l y , th e s e f u n d s w o u l d b e u s e d f o r s i t e i n v e s t i g a t i o n , r ec o n n a i s s a n c e an d e n g i n e e r i n g p l a n s f o r a r e c l a m a t i o n e f f o r t . Ci t y o f A s p e n a n d Pi t k i n C o u n t y Wi l d f i r e 1. P r o v i d e f i r e p r o t e c t i o n f o r b o t h t h e C a s t l e a n d Ma r o o n C r e e k in t a k e s t r u c t u r e s a n d L e o n a r d T h o m a s R e s e r v o i r i n c l ud i n g t h e po t e n t i a l t o c l e a r f u e l s a n d m o d i f y t h e i n t a k e s t r u ct u r e s . 2. C o n t i n u e d e v e l o p i n g a p l a n f o r L e o n a r d T h o m a s R e se r v o i r an d e v a l u a t e b o t h i n t a k e s t r u c t u r e s t o d e t e r m i n e h o w b e s t t o pr o t e c t t h e m f r o m p o s t w i l d f i r e d e b r i s f l o w . 3. D i s t r i b u t e t h e f i n a l s o u r c e w a t e r p r o t e c t i o n p l a n t o t h e U S F S . C i t y o f A s p e n C i t y o f A s p e n C i t y o f A s p e n Fl o o d s / L a n d s l i d e s / A v a l a n c h e De b r i s F l o w 1. U t i l i z e c u r r e n t p r o c e s s t o n o t i f y t h e p u b l i c i n ca s e o f a ca t a s t r o p h i c e v e n t . 2. S w i t c h w a t e r s o u r c e s , i f n e c e s s a r y , t o c o n t i n u e to p r o v i d e dr i n k i n g w a t e r t o C i t y o f A s p e n c u s t o m e r s . C i t y o f A s p e n C i t y o f A s p e n Ab i l i t y t o M a n a g e E m e r g e n c y Fl o w s i n t o a n d o u t o f t h e Re s e r v o i r 1 . D e v e l o p a d r e d g i n g m a i n t e n a n c e s c h e d u l e t o m a in t a i n i n t e n d e d s t o r a g e a n d f r e e b o a r d 2 . E v a l u a t e t h e m e t h o d s a v a i l a b l e t o d e l i v e r a l l e x p e c t e d f l o w s f r o m L e o n a r d T h o m a s R e s e r v o i r t o C a s t l e C r e e k , o r a n o t h e r v i a b l e d r a i n a g e w a y . 3 . F o l l o w C C R 4 0 2 - 1 s e c t i o n 1 2 . 3 . 2 f o r n o t i c i n g Di v i s i o n E n g i n e e r w h e n l a r g e r e l e a s e s m a y b e n e c e s s a r y . 4 . E v a l u a t e L e o n a r d T h o m a s R e s e r v o i r b r e a c h /ov e r t o p p i n g s c e n a r i o a n d c o n v e y a n c e s y s t e m a n d s t r a t e g y . C i t y o f A s p e n C i t y o f A s p e n C i t y o f A s p e n C i t y o f A s p e n P51 I. 47 Se c u r i t y 1 . M a i n t a i n e x i s t i n g S u p e r v i s o r C o n t r o l & D a t a A cq u i s i t i o n ( S C A D A ) m o n i t o r i n g a n d d a i l y s i t e v i s i t s t o m o n i to r s e c u r i t y . 2 . I n s t a l l f e n c i n g a r o u n d t h e s u r f a c e w a t e r i n t a ke f a c i l i t i e s ( u p o n l a n d o w n e r c o n s u l t a t i o n a n d a p p r o v a l ) . 3 . I n s t a l l s e c u r i t y c a m e r a s a t b o t h i n t a k e s a n d pr o v i d e a r e l i a b l e c o m m u n i c a t i o n c o n n e c t i o n . C i t y o f A s p e n C i t y o f A s p e n C i t y o f A s p e n Re s i d e n t i a l P r a c t i c e s 1 . C o n d u c t a p u b l i c e d u c a t i o n a n d o u t r e a c h p r o g r am t o r e s i d e n t s a b o v e t h e C a s t l e C r e e k i n t a k e a n d i n A sp e n ’ s E a s t E n d t o e n c o u r a g e p r a c t i c e s t h a t w i l l p r o t e c t t h e ir d r i n k i n g w a t e r s o u r c e s . Ci t y o f A s p e n an d Pi t k i n C o u n t y Re s t a u r a n t s 1 . C o n d u c t e d u c a t i o n a n d o u t r e a c h t o r e s t a u r a n t s h i g h l i g h t i n g w a s t e d i s p o s a l b e s t m a n a g e m e n t p r a c t i c e s . C i t y o f A s p e n Ro a d s : V e h i c l e s a n d S a n d i n g 1 . E v a l u a t e t h e n e e d f o r a C o n t i n g e n c y / E m e r g e n c y A c t i o n P l a n t o a d d r e s s r o a d r e l a t e d a c c i d e n t s , f u e l s p i l l s a nd a p p l i c a t i o n o f r o a d d e i c i n g m a t e r i a l s . 2 . I d e n t i f y a r e a s a b o v e t h e C a s t l e C r e e k i n t a k e th a t a r e s u s c e p t i b l e t o v e h i c l e s r u n n i n g o f f t h e r o a d a n d r e q u e s t P i t k i n C o u n t y t o i n c l u d e t h e s e a r e a s w h e n p l a n n i n g f o r an d i n s t a l l i n g g u a r d r a i l s . 3 . D i s t r i b u t e t h e f i n a l s o u r c e w a t e r p r o t e c t i o n pl a n t o P i t k i n C o u n t y E n v i r o n m e n t a l H e a l t h , C o m m u n i t y D e v e l o p m e nt , O f f i c e o f E m e r g e n c y M a n a g e m e n t a n d R o a d a n d B r i d g e d e p a rt m e n t s ; C i t y o f A s p e n D e p a r t m e n t s o f C o m m u n i t y D e v e l o p m e nt , E n v i r o n m e n t a l H e a l t h , E n g i n e e r i n g , S t r e e t s , a n d As s e t M a n a g e m e n t ; t h e A s p e n F i r e D i s t r i c t ; t h e P i t k i n Co u n t y B o a r d o f C o m m i s s i o n e r s ; t h e A s p e n C i t y C o u n c i l ; a n d t h e U S F S . Ci t y o f A s p e n an d Pi t k i n C o u n t y Ci t y o f A s p e n an d Pi t k i n C o u n t y Ci t y o f A s p e n a n d Pi t k i n C o u n t y P52 I. 48 TABLES AND FIGURES Table 1: Page 5 Primary Contact Information for the City of Aspen Table 2: Page 6 Planning Meetings Figure 1: Page 8 Some Steering Committee Members on the tour of Smuggler Mine to see firsthand how the local mines were constructed. Table 3: Page 8 Stakeholders and Steering Committee Members Figure 2: Page 10 City of Aspen Location in Colorado Figure 3: Page 13 Castle and Maroon Creek Watersheds Table 4: Page 14 Groundwater Supply Information Table 5: Page 14 Surface Water Supply Information: Figure 4: Page 15 Castle Creek Intake Figure 5: Page 15 Maroon Creek Intake Figure 6: Page 16 Water System Process Schematic Figure 7: Page 18 Source Water Assessment and Protection Phases Figure 8: Page 21 City of Aspen Groundwater Source Water Protection Areas Figure 9: Page 22 City of Aspen Surface Water Source Water Protection Areas Figure 10: Page 23 Leonard Thomas Reservoir Source Water protection Areas Figure 11: Page 24 Schematic Drawing of the Potential Sources of Contamination to the Drinking Water Supply Table 6: Page 27 Priority Strategy for Castle and Maroon Creeks Table 7: Page 27 Priority Strategy for Groundwater Wells Table 8: Page 28 Priority Strategy for Leonard Thomas Reservoir Table 9: Page 29 Updated Susceptibility Analysis Figure 12: Page 31 Pitkin Iron Mine Location Figure 13: Page 32 Pitkin Iron Mine Mill Site Location 1 Figure 14: Page 32 Pitkin Iron Mine Mill Site Drainage System and Permitted Area. Figure 15: Page 33 Pitkin Iron Mine and Mill Site Location in Relation to Castle Creek Figure 16: Page 33 Pitkin Iron Mine Mill Site Location 2 Figure 17: Page 34 Pitkin Iron Mine Mill Site Location 3 Figure 18: Page 35 Wildfire in Relation to Community Water System Figure 19: Page 36 Buffalo Creek Wildfire Post Wildfire Debris and Mudflow Figure 20: Page 37 Pitkin County Wildfire Hazards Map Figure 21: Page 39 Raging flood destroying a bridge along Highway 34 toward Estes Park, Colo. Figure 22: Page 41 Residential Practices Figure 23: Page 42 Improper FOG Disposal Table 10: Page 46 Source Water Protection Best Management Practices P53 I. 49 REFERENCES Bryant, B. 1979. Geology of the Aspen 15-minute Quadrangle, Pitkin and Gunnison counties, Colorado. Geological Survey Professional Paper 1073, USGPO, Washington, DC. 146 pgs. California Environmental Protection Agency, “Fats, Oils and Grease (FOG) Management Control Program” http://www.waterboards.ca.gov/coloradoriver/water_issues/programs/pretreatment/docs/intr o_fog_inspections.pdf City of Aspen/Pitkin County, http://www.aspenpitkin.com/Exploring-the-Valley/History/ Colorado Department of Public Health and Environment, Source Water Assessment and Protection: https://www.colorado.gov/pacific/cdphe/source-water-assessment-and-protection-swap Colorado Department of Public Health and Environment, WQ Standards, 2013 http://www.colorado.gov/cs/Satellite?c=Page&childpagename=CDPHE- WQCC%2FCBONLayout&cid=1251590910618&pagename=CBONWrapper Colorado State Forest Service: Pitkin County Wildland Fire Plan, 2014 http://csfs.colostate.edu/media/sites/22/2014/02/PitkinCountyCommunityWildfireProtectionPl an-Update2014.pdf Colorado: The Official State Web Portal, “Colorado commemorates anniversary of September 2013 floods, focuses on 100 percent long-term recovery for local communities, September 28, 2014” http://www.colorado.gov/cs/Satellite/GovHickenlooper/CBON/1251656686190 Copeland, Claudia, “Terrorism and Security Issues Facing the Water Infrastructure Sector” Congressional Research Service, December, 2010 http://www.fas.org/sgp/crs/terror/RL32189.pdf ENARTECH, Inc., City of Aspen: Implications of Ground Water Withdrawals on Local Stream Flow Conditions. 1997 Freeman, V.L. 1971. Stratigraphy of the State Bridge Formation in the Woody Creek Quadrangle, Pitkin and Eagle counties, Colorado. Contributions to stratigraphy, Geological Survey Bulletin 1324-F.USGPO, Washington, DC. 17 pgs. Green, G. N., 1992. The digital geologic map of Colorado in ARC/INFO Format: U.S. Geological Survey Open-File Report 92-507, U.S. Geological Survey, Denver. Google Maps: http://maps.google.com/maps?hl=en&tab=wl P54 I. 50 Gowler A. and Sage R. (2006) Traffic and Transport: Potential Hazards and Information Needs. In O. Schomoll, J. Howar, J. Chilton, I. Chorus, Protecting Groundwater Health. IWA Publishing. London, UK. Ground Water Atlas of Colorado, 2003 http://geosurvey.state.co.us/WATER/GROUNDWATERATLAS/Pages/GroundwaterAtlasofColora do.aspx Ground Water Protection Council. (2008). Ground Water Report to the Nation: A Call to Action. Oklahoma City, Oklahoma: Ground Water Protection Council. http://www.gwpc.org/sites/default/files/GroundWaterReport-2007-.pdf KMGH Channel 7, Denver Meixner, Tom, Wohlgmuth, Peter, (2004) Wildfire Impacts on Water Quality. Southwest Hydrology. Michigan Department of Environmental Quality, “Restaurant Pollution Prevention: Everything you wanted To Know About FOG” http://www.michigan.gov/documents/deq/deq-ess-p2-restaurant-FOGbrochure_302504_7.pdf Olander, H.C., N.B. Lamm, and B.A. Florquist. 1974. Roaring Fork and Crystal valleys an environmental and engineering study. Environmental Geology No. 8, CO Geological Survey Pitkin Iron Mine, http://westernmininghistory.com/mine_detail/10012411 Roaring Fork Conservancy, 2008 State of the Watershed Roaring Fork Report http://www.roaringfork.org/sitepages/pid272.php Seawell C. and Agbenowosi N. (1998). Effects of Road Deicing Salts on Groundwater Systems. June 1998. www.cee.vt.edu/ewr The Weather Channel, AP Photo/Colorado Heli-Ops, Dennis Pierce http://www.weather.com/news/news/colorado-flood-aerials-show-destruction-photos- 20130916 Tweto, O., 1979. The geologic map of Colorado: Special Publication. U.S.Geological Survey, Reston, Virginia. US Climate Data Aspen: http://www.usclimatedata.com/climate/aspen/colorado/united-states/usco0016 P55 I. 51 US EPA, Planning for Disaster Debris http://www.epa.gov/wastes/conserve/imr/cdm/pubs/disaster.htm#volume Walsh Environmental Scientists and Engineers, LLC. “Garfield County Community Wildfire Protection Plan.” November 2012. http://www.garfield-county.com/emergency-management/documents/Garfield-County- Community-Wildfire-Protection-Plan.pdf Washington State Department of Health, 2010, Flood Advice for Drinking Water Systems http://www.doh.wa.gov/Portals/1/Documents/Pubs/331-300.pdf Waskom, R, Bauder, T., (2011), A Homeowners Guide to Protecting Water Quality and the Environment, Colorado State University Cooperative Extension. Wikipedia - http://en.wikipedia.org/wiki/Aspen,_Colorado Williams, C. (February 2013). Town of Jamestown Source Water Protection Plan. Colleen Williams, Colorado Rural Water Association. Pueblo, Colorado. P56 I. 52 APPENDICES4 A. Water Quality Standards Table B. Contingency Plan C. Source Water Assessment Report D. Source Water Assessment Report Appendices E. MOU between CDPHE and U.S. Forest Service Rocky Mountain Region F. Table A-1 Discrete Contaminant Types G. Table A-2 Discrete Contaminant Types (SIC Related) H. Table B-1 Dispersed Contaminant Types I. Table C-1 Contaminants Associated with Common PSOC’s 4 All appendices are located on the CD version of this SWPP. P57 I. AN O R D I N A N C E CO N C E R N I N G T H E C O N S T R U C T I O N A N D O P E R A T I O N O F WA T E R W O R K S I N T H E T O W N O F A S P E N . -- - - - - - - Be I t O r d a i n e d b y t h e B o a r d o f T r u s t e e s o f t h e T o w n o f A s p e n : S EC T I O N 1 . Th a t H . P . C o w e n h o v e n a n d D a v i d R . C . B r o w n , t h e i r a s s o c i a t e s or a s s i g n s , a r e h e r e b y g r a n t e d t h e r i g h t t o e s t a b l i s h , c o n s t r u c t, o p e r a t e , a n d m a i n t a i n wa t e r w o r k s w i t h i n o r w i t h o u t t h e c o r p o r a t e l i m i t s o f t h e t o w n o f A s p e n , f o r t h e pu r p o s e o f s u p p l y i n g t h e s a i d t o w n o f A s p e n a n d i t s i n h a b i t a n t s w i t h w a t e r f o r f i r e , do m e s t i c , a n d o t h e r p u r p o s e s , a n d f o r t h a t p u r p o s e t o l a y t h e i r w a t e r m a i n s a n d p i p e s un d e r t h e s u r f a c e o f a n y a n d a l l t h e s t r e e t s , a v e n u e s , a l l e y s , an d p u b l i c p l a c e s o f s a i d to w n , a n d t h e y a r e a u t h o r i z e d t o e x c a v a t e t r e n c h e s u p o n s a i d s t re e t s , a v e n u e s , a l l e y s an d p u b l i c p l a c e s f o r t h e p u r p o s e o f l a y i n g s u c h m a i n s o r p i p e s , o r t h e r e p a i r i n g o r re p l a c i n g o f t h e s a m e ; p r o v i d e d t h a t s u c h w o r k s h a l l b e d o n e i n s u c h m a n n e r a s t o gi v e t h e l e a s t p o s s i b l e i n c o n v e n i e n c e t o t h e p u b l i c o r i n d i v i d u al s i n t h e u s e o f s u c h st r e e t s , a v e n u e s , a l l e y , a n d p u b li c p l a c e s ; a n d , p r o v i d e d , t h a t t r e n c h e s , a s s o o n a s pr a c t i c a b l e a f t e r b e i n g e x c a v a t e d b e f i l l e d , a n d t h e s t r e e t s , a ve n u e s , a n d a l l e y s b e le f t i n a s g o o d o r d e r a s p r a c t i c a b l e a s p r o m p t l y a s p o s s i b l e a f te r p i p e s a r e l a i d ; pr o v i d e d , t h a t a l l t r e n c h e s , d i t c he s a n d o t h e r e x c a v a t i o n s m a d e b y s a i d C o w e n h o v e n an d B r o w n , t h e i r a s s o c i a t e s o r a s s i g n s , i n t h e c o n s t r u c t i o n o r re p a i r o f s a i d w o r k s , ma i n s o r p i p e s s h a l l b e p r o t e c t e d b y l i g h t s a n d b a r r i c a d e s s u f f ic i e n t t o w a r n pa s s e n g e r s o f t h e e x i s t e n c e o f s u c h e x c a v a t i o n s . S EC T I O N 2 . T h e j u r i s d i c t i o n o f t h e t o w n o f A s p e n s h a l l e x t e n d o v e r t h e t e r r i t o r y oc c u p i e d b y s u c h w a t e r w o r k s , a n d a l l r e s e r v o i r s , s t r e a m s , t r e n c h e s , p i p e s a n d d r a i n s us e d i n a n d n e c e s s a r y f o r t h e c o n s t r u c t i o n , m a i n t e n a n c e a n d o p e ra t i o n o f t h e s a m e an d i n t h e s t r e a m s o r s o u r c e f r o m w h i c h t h e w a t e r i s t a k e n , f o r t h e p u r p o s e o f ma i n t a i n i n g a n d p r o t e c t i n g s u c h w or k s f r o m i n j u r y a n d t h e w a t e r f u r n i s h e d t h e r e b y fr o m p o l l u t i o n , a n d s a i d t o w n s h a l l e n a c t a l l o r d i n a n c e s a n d r e gu l a t i o n s n e c e s s a r y to c a r r y t h e p o w e r h e r e i n co n f e r r e d i n t o e f f e c t . S EC T I O N 3 . S a i d H . P . C o w e n h o v e n a n d D . R . C . B r o w n , t h e i r a s s o c i a t e s or as s i g n s , s h a l l h a v e t h e r i g h t t o e x c a v a t e t r e n c h e s i n s a i d s t r e et s , a v e n u e s , a l l e y s a n d 10 6 GE N E R A L O R D I N A N C E . 1 0 7 pu b l i c p l a c e s , a n d t o d i s t u r b o r i n t e r f e r e w i t h t h e s u r f a c e t h e reof, and to use the same fo r t h e p u r p o s e o f l a y i n g s u c h m ai n s a n d p i p e s a f o r e s a i d . A n d n o person shall, wi t h o u t t h e w r i t t e n p e r m i s s i o n o f s a i d H . P . C o w e n h o v e n a n d D . R . C. Brown, their as s o c i a t e s o r a s s i g n s , s i g n e d b y t h e m o r t h e i r o f f i c e r o r a g e n t thereunto duly au t h o r i z e d , m a k e a n y e x c a v a t i o n o r t r e n c h e s i n a n y o f s a i d s t r e ets, avenues, alleys or p u b l i c p l a c e s f o r t h e p u r p o s e o f l a y i n g w a t e r p i p e s t h e r e i n connecting with the ma i n s o f s a i d H . P . C o w e n h o v e n a n d D . R . C . B r o w n , t h e i r a s s o ciates or assigns, an d s a i d H . P . C o w e n h o v e n a n d D . R . C . B r o w n , t h e i r a s s o c i a t e s or assigns, shall be r e s p o n s i b l e t o t h e t o w n o f A s p e n f o r a l l w o r k d o n e o n s u c h s treets, avenues, al l e y s a n d p u b l i c p l a c e s u n d e r s u c h w r i t t e n p e r m i s s i o n t o t h e same extent as if such wo r k h a d b e e n d o n e b y t h e m . A n y p e r s o n w h o s h a l l v i o l a t e a n y o f the provisions of th i s s e c t i o n s h a l l , o n c o n v i c t i o n , b e f i n e d n o t l e s s t h a n t e n d ollars ($10.00) nor more th a n o n e h u n d r e d d o l l a r s ( $ 1 0 0 . 0 0 ) . S EC T I O N 4 . I f a n y p e r s o n s h a l l , w i t h o u t a u t h o r i t y f r o m H . P . C o w e n h o v en and D. R . C . B r o w n , t h e i r a s s o c i a t e s o r a s s i g n s , s o t o d o , t a p o r b reak or otherwise injure an y m a i n o r p i p e u s e d b y s a i d H . P . C o w e n h o v e n a n d D . R . C . B r o wn, their as s o c i a t e s o r a s s i g n s , f o r t h e c o n d u c t i n g o r f l o w o f w a t e r , or shall in any ma n n e r i n j u r e a n y r e s e r v o i r , t r e n c h , p i p e o r d r a i n u s e d i n a nd necessary for the co n s t r u c t i o n , m a i n t e n a n c e o r o p er a t i o n O f t h e w a t e r w o r k s o f said H. P. Co w e n h o v e n a n d D . R . C . B r o w n o r t h e i r a s s o c i a t e s o r a s s i g n s ; or if any person sh a l l c a s t o r d e p o s i t , o r c a u s e t o b e c a s t o r d e p o s i t e d , o r i n any manner aid in ca s t i n g o r d e p o s i t i n g a n y e a r t h , f i l t h o r s e d i m e n t , o r a n y m a t e rial, or anything wh a t s o e v e r , i n t o t h e s t e a m o r s o u r c e f o r f i v e ( 5 ) m i l e s a b o v e the point therein from wh i c h s u c h w a t e r i s o r s h a l l b e t a k e n , w h e r e b y s u c h w a t e r shall in any way be po l l u t e d o r t h e t r a n s p a r e n c y t h e r e o f a f f e c t e d o r i t s q u a l i t y in any way deteriorated, in j u r e d o r i m p a i r e d , e v e r y p e r s o n s o o f f e n d i n g s h a l l b e d e e m e d guilty of a mi s d e m e a n o r , a n d o n c o n v i c t i o n t h er e o f s h a l l b e f i n e d n o t l e s s than fifty dollars ($ 5 0 . 0 0 ) n o r m o r e t h a n o n e h un d r e d d o l l a r s ( $ 1 0 0 . 0 0 ) f o r e a ch offense. And in ca s e · o f c o n t i n u i n g p o l l u t i o n o r i n j u r y o f s a i d w a t e r , e v e r y t w enty-four (24) hours of t h e c o n t i n u a n c e o f t h e s a m e s h a l l b e d e e m e d a n d h e l d a s e p a r ate offense. S EC T I O N 5 . S a i d H . P . C o w e n h o v e n a n d D . R . C . B r o w n , t h e i r a s s o c i a t e s or as s i g n s , s h a l l m a k e s u c h r e a s o n a b l e r u l e s a n d r e g u l a t i o n s f o r t he government of pl u m b e r s a n d p r e s c r i b i n g t h e m a n n e r i n w h i c h t h e i r w o r k s h a l l be done, and co n n e c t i o n s m a d e w i t h t h e i r m a i n s a n d p i p e s , a n d p r o v i d i n g s u c h restrictions as to th e t i m e a n d m e t h o d o f d o i n g s a i d w o r k a s m a y b e n e c e s s a r y f o r the protection of sa i d H . P . C o w e n h o v e n a n d D . R . C . B r o w n , t h e i r a s s o c i a t e s o r a ssigns, in the rights an d p r i v i l e g e s h e r e i n b e f o r e g r a n t e d , a n d f o r t h e p u r p o s e o f p romoting the P58I. 108 G E N E R A L O R D I N A N C E . co n v e n i e n c e a n d s a f e t y o f t h e p u b l i c , w h i c h r i d e s a n d r e g u l a t i o ns s h a l l a t a l l t i m e s be o p e n t o t h e i n s p e c t i o n o f a n y o f f i c e r o f t h e t o w n o f A s p e n a nd a l l o t h e r p e r s o n s in t e r e s t e d . A n d e v e r y p e r s o n , f i r m , a s s o c i a t i o n o r c o r p o r a t i o n c a r r y i n g o n a pl u m b i n g b u s i n e s s i n t h e t o w n o f A s p e n s h a l l , i n t h e p e r f o r m a n c e o f h i s , t h e i r o r i t s wo r k , c o n f o r m t o s a i d r u l e s a n d r e g u l a t i o n s , a n d s h a l l , a s s o o n a s p r a c t i c a b l e a f t e r th e r e m o v a l o f a n y p a v e m e n t o r s i d e w a l k , f o r t h e p u r p o s e o f s u c h w o r k , r e p l a c e t h e sa m e i n a s g o o d a n d a s d u r a b l e a c o n d i t i o n a s t h e s a m e w a s i n p ri o r t o r e m o v a l . Ev e r y s u c h p e r s o n , f i r m , a s s o c i a t i o n o r c o r p o r a t i o n s h a l l , b e f o re e n g a g i n g i n s a i d bu s i n e s s , o r i n t e r f e r i n g w i t h a n y s i d e w a l k i n s a i d t o w n , p r o c u r e a l i c e n s e t h e r e f o r , an d s h a l l p a y t h e r e f o r t h e s u m o f s i x t y d o l l a r s ( $ 6 0 . 0 0 ) f o r o n e y e a r , o r t h e s u m o f th i r t y - f i v e d o l l a r s ( $ 3 5 . 0 0 ) f o r s i x m o n t h s , a n d s h a l l e x e c u t e to t h e t o w n o f A s p e n a bo n d i n t h e p e n a l s u m o f t h r e e t h o u s a n d d o l l a r s ( $ 3 , 0 0 0 . 0 0 ) w i t h s e c u r i t i e s t o b e ap p r o v e d b y t h e m a y o r , c o n d i t i o n e d f o r t h e f a i t h f u l p e r f o r m a n c e b y s u c h p a r t y o f al l t h e p r o v i s i o n s o f t h i s s e c t i o n , a n d f o r c o n f o r m i t y t o t h e r ul e s a n d r e g u l a t i o n s af o r e s a i d , a n d t h e p a y m e n t o f a ll d a m a g e s f o r w h i c h t h e t o w n m a y b e c o m e l i a b l e by r e a s o n o f a n y n e g l i g e n c e o r i m p r o p e r p e r f o r m a n c e o f a n y w o r k a f o r e s a i d . A n y pe r s o n o r p e r s o n s w h o s h a l l e n g a g e i n t h e b u s i n e s s a f o r e s a i d w i th o u t f i r s t h a v i n g ob t a i n e d s u c h l i c e n s e a s a f o r e s a i d , o r h a v i n g o b t a i n e d s u c h l i c en s e , s h a l l v i o l a t e a n y of t h e p r o v i s i o n s o f t h i s s e c t i o n s h a l l , o n c o n v i c t i o n , b e f i n e d i n a n y s u m n o t l e s s th a n t e n d o l l a r s ( $ 1 0 . 0 0 ) n o r m o r e t h a n o n e h u n d r e d d o l l a r s ( $ 1 00 . 0 0 ) . S EC T I O N 6 . T h e g r a n t c o n t a i n e d i n t h i s o r d i n a n c e i s m a d e i n p u r s u a n c e o f a pr o p o s i t i o n m a d e t o t h e m a y o r a n d b o a r d o f t r u s t e e s o f t h e t o w n o f A s p e n o n t h e 20 th d a y o f O c t o b e r , 1 8 8 5 , a n d w h i c h w a s b y s a i d b o a r d o f t r u s t e e s of s a i d t o w n , o n th e 3 1 st d a y o f O c t o b e r , 1 8 8 5 , a c c e p t e d , s u b j e c t t o a v o t e o f t h e l e g a l v o t e r s o f t h e to w n o f A s p e n , o n t h e q u e s t i o n o f a p p r o v i n g t h e a u t h o r i z a t i o n b y t h e b o a r d o f tr u s t e e s o f s a i d t o w n o f t h e e r e c t i o n o f w a t e r w o r k s b y t h e H . P . C o w e n h o v e n a n d D . R. C . B r o w n , w h i c h s a i d a u t h o r i z a t i o n w a s b y a m a j o r i t y o f t h e le g a l v o t e r s o f t h e to w n o f A s p e n v o t i n g o n s u c h q u e s t i o n a t a s p e c i a l e l e c t i o n h e l d o n t h e 5 th d a y o f No v e m b e r , 1 8 8 5 , a p p r o v e d , a n d s ai d p r o p o s i t i o n i s h e r e b y a c c e p t ed a n d m a d e a bi n d i n g c o n t r a c t b e t w e e n t h e t o w n o f A s p e n a n d t h e s a i d H . P . C o we n h o v e n a n d D. R . C . B r o w n , a n d s a i d c o n t r a c t a n d t h i s o r d i n a n c e s h a l l c o n s t it u t e a n d d e f i n e t h e au t h o r i t y a n d r i g h t s o f s a i d C o w e n h o v e n a n d B r o w n , t h e i r a s s o ci a t e s o r a s s i g n s . S EC T I O N 7 . T h e g r a n t c o n t a i n e d i n t h i s o r d i n a n c e a n d a l l t h e r i g h t s , pr i v i l e g e s an d i m m u n i t i e s h e r e i n b e f o r e pr o v i d e d f o r , s h a l l b e a n d c o n t i n u e i n f o r c e f o r a p e r i o d of t w e n t y ( 2 0 ) y e a r s f r o m t h e 3 1 st d a y o f O c t o b e r , 1 8 8 5 . S EC T I O N 8 . A l l o r d i n a n c e s o r p a r t s o f o r d i n a n c e s i n c o n f l i c t w i t h o r in c o n s i s t e n t wi t h t h i s o r d i n a n c e a r e h e r e b y r e p e a l e d . GE N E R A L O R D I N A N C E . 1 0 9 P a s s e d a n d a p p r o v e d b y t h e b oa r d o f t r u s t e e s o f t h e t o w n o f Aspen this 11 th day of N o v e m b e r , 1 8 8 5 . C H A R L E S R E E S E , M AYOR. A t t e s t : J O H N F . M c E V O Y , R EC O R D E R P R O T E M .   P59I. Page 1 of 3 MEMORANDUM TO: Mayor and City Council FROM: Phil Overeynder, Utilities Engineer-Special Projects THRU: Dave Hornbacher, Director Utilities and Environmental Initiatives DATE OF MEMO: May 12, 2016 MEETING DATE: May 16, 2016 RE: 2016 Water Supply Availability Study Update REQUEST OF COUNCIL: Council is requested to adopt as a planning document an updated study regarding the availability of raw water supplies that serves Aspen’s future water needs. PREVIOUS COUNCIL ACTION: The Water Supply Availability study was previously updated in April 2000 with additional analysis performed in 2009 in connection with an update to the Aspen Area Community Plan (AACP). Information contained in the availability study was incorporated into the “Existing Conditions” section of the AACP. The Climate Change Resiliency Plan adopted by Council in 2015 contained a water supply element which encouraged development of more specific tools related to assessing a shift in climate that will affect the adequacy of future water supplies. BACKGROUND: An analysis of raw water availability has been performed at approximately 10 year intervals beginning in 1984. The purpose of this analysis is to provide an estimate of long term water supply needs and compare those needs to available supplies in order to identify potential gaps. Previous studies identified projects or other actions were then implemented to address any expected gaps in water supply and the potential timing of projects, within the planning horizon. These studies were incorporated into a Comprehensive Water Management Program (CWMP) including the Asset Management Plan (updated annually) which provides financial resources to address specific water supply needs. Updates to the availability study were provided in 1994 and 2000 and in 2009, as noted above, in connection within the AACP Update. Previous analyses have considered the adequacy of Aspen’s raw water supplies under various growth scenarios using historical hydrology (estimate of available streamflows at supply points, based on past streamflow conditions). Those analyses did not address climate change impacts. DISCUSSION: The 2016 analysis extends the planning horizon to a 50-year period while evaluating a range of impacts to water supplies that are expected to result from several climate change models. Notably, climate change models predict an earlier initiation of runoff with more P60 II. Page 2 of 3 variability between wet and dry periods. Extended periods of low flow conditions in local streams are expected to result from the earlier commencement of runoff, whether or not the climate becomes wetter or drier overall. The identified water supply gaps depend on a number of key variables and assumptions that provide the basis for the study. First, the analyses assume that the City’s policy (reflected in numerous documents including the ecological bill of rights as well as Resolution 93-5) to protect in-stream flow will be maintained even during the driest periods. Second, the analyses include a number of different water demand scenarios reflecting three different levels of development, forecast over a 50-year planning horizon. In addition, five climate change scenarios were analyzed that reflect at least 80% of the variability between hundreds of versions of climate models describing future hydrologic conditions for Colorado. Finally, the extent that existing water rights that are junior to Aspen’s rights and to the instream flow rights are administered in priority order (historical practice vs. strict administration) are also analyzed in the study. One conclusion of the study is that no supply gaps would exist with any of the projected water needs if historical hydrologic conditions were maintained. However, considering climate shifts, the study identifies potential gaps and compares the “tool box” of water supply programs that are currently available to address the expected gaps. Because the supply forecast is analyzed over a 50-year period and because the shift in climate is also projected over a similar period, the report recommends that Aspen should monitor some key factors to determine which scenario best describes actual trends over time. The majority of the data to be collected under these recommendations is already being collected at various monitoring sites within the Roaring Fork valley, but it will be necessary to compile that information to provide an accurate tracking of shifts in hydrology in the Aspen area resulting from climate change. This information will inform further updates and refinement of the Water Supply Availability Study, and project planning decisions. FINANCIAL/BUDGET IMPACTS: The water supply projects and programs that have been identified in order to address supply gaps in the mid-term (10-20 year planning horizon) are already contained in the City’s Asset Management Plan. There will be some additional costs associated with compiling the meteorological and hydrologic data needed to track hydrological shifts. Staff will provide a more detailed estimate of these costs prior to City Council action on the study. ENVIRONMENTAL IMPACTS: The water supply availability study is intended to support the Climate Change Resiliency Plan as described above. Projects and activities necessary to address mid-term water supply gaps are already underway. How specific future projects will meet longer term water supply needs will need to be addressed as more specific water supply projects are identified, and as more detailed local data on climate change impacts becomes available. RECOMMENDED ACTION: Staff recommends that Council set a public hearing to consider adoption of the recommendations contained in the Water Supply Availability Study (2016 Update). P61 II. Page 3 of 3 CITY MANAGER COMMENTS: ATTACHMENTS: Attachment A--Water Supply Availability Study 2016 Update P62 II. City of Aspen Water Supply Availability Study – 2016 Update DRAFT CITY OF ASPEN WATER SUPPLY AVAILABILITY STUDY 2016 UPDATE Prepared for: City of Aspen March 2016 P63 II. i TABLE OF CONTENTS Page 1.0 INTRODUCTION ................................................................................................................... 1 2.0 BACKGROUND ....................................................................................................................... 2 3.0 METHODS .............................................................................................................................. 4 3.1 Demand Scenarios .............................................................................................................. 4 3.1.1 Demand Scenario 1A – Existing Baseline Demand ........................................... 4 3.1.2 Demand Scenario 2A – Historical Growth Rate of 1.2% ................................... 5 3.1.3 Demand Scenario 2B – Restricted Development ............................................. 5 3.1.4 Demand Scenario 3A – CO State Demographer Growth Rate of 1.8% ............. 6 3.2 Hydrology Scenarios ........................................................................................................... 7 3.3 Streamflow Model Assumptions......................................................................................... 9 4.0 RESULTS .............................................................................................................................. 10 4.1 Demand Scenario 1A – Existing Baseline Demand ........................................................... 10 4.2 Demand Scenario 2A – Historical Growth Rate 1.2% ....................................................... 11 4.3 Demand Scenario 2B – Restricted Development .............................................................. 12 4.4 Demand Scenario 3A – CO State Demographer Growth Rate 1.8% ................................. 13 4.5 Alternate Herrick Ditch Operation, Demand Scenario 3A ................................................ 14 5.0 ALTERNATE WATER SUPPLIES AND THEIR POTENTIAL IMPLEMENTATION .............................. 16 5.1 Alternate Water Supply Options ....................................................................................... 16 5.1.1 Wastewater Reuse Program ........................................................................... 16 5.1.2 Water Restrictions (Potable and Non-Potable Water Uses) .......................... 17 5.1.3 Municipal Wells .............................................................................................. 17 5.2 Implementation of Alternate Water Supply Options ....................................................... 18 5.2.1 Demand Scenario 1A – Existing Baseline Demand ......................................... 18 5.2.2 Demand Scenario 2A – Historical Growth Rate 1.2% ..................................... 18 5.2.3 Demand Scenario 2B – Restricted Growth ..................................................... 18 5.2.4 Demand Scenario 3A – CO State Demographer Growth Rate 1.8% ............... 19 5.2.5 Alternate Herrick Ditch Operation, Demand Scenario 3A .............................. 19 6.0 DISCUSSION ......................................................................................................................... 19 7.0 RECOMMENDATIONS ........................................................................................................... 20 8.0 REFERENCES ........................................................................................................................ 23 P64 II. ii TABLES Table 1. Monthly Water Demands SCENARIO 1A Table 2. Monthly Water Demands SCENARIO 2A Table 3. Monthly Water Demands SCENARIO 2B Table 4. Monthly Water Demands SCENARIO 3A Table 5. CMIP3 Model Scenario Statistics Table 6. Scenario Summary Matrix Table 7. Scenario Summary Matrix – Assuming No Curtailment of Diversions Table 8. City of Aspen Water Restriction Stages and Water Savings Target FIGURES Figure 1. City of Aspen Municipal Water Supply Figure 2. Climate Scenarios – Average Monthly Maroon Creek Streamflow Figure 3. Demand Scenario 1A Irrigation and Non-Irrigation ISF Deficits Figure 4. Demand Scenario 2A Irrigation and Non-Irrigation ISF Deficits Figure 5. Demand Scenario 2B Irrigation and Non-Irrigation ISF Deficits Figure 6. Demand Scenario 3A Irrigation and Non-Irrigation ISF Deficits Figure 7. Herrick Ditch Alt. Operation & Demand Scenario 3A Irrigation and Non-Irrigation ISF Deficits P65 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 1 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT 1.0 INTRODUCTION As a municipal water provider, the City of Aspen (City) is charged with ensuring a reliable and safe water supply to its customers. Accordingly, the City completes periodic evaluations to ensure available water supplies are sufficient to meet existing and foreseeable future water demands. This study builds on, and updates previous studies completed by Sheaffer & Roland, Inc., and ENARTECH Inc. completed in 1984, 1994, and 2000. These studies provide a detailed description of the existing City owned water rights and associated water delivery infrastructure. The most recent raw water availability assessment completed by ENARTECH in 2000 suggest that all potable water demands modeled can be supplied by existing water resources, however in the late summer of drier than average years, raw water shortages may exist on the order of 1.0 cubic foot per second (cfs) or less. Since 2000, City water demands have changed in response to increased delivery efficiencies, population growth, and water supply agreements to serve additional areas with City water. In addition, climate change and the associated changes in streamflow are beginning to be better understood. As a result, the City wishes to update the 2000 Raw Water Availability study as a part of their Comprehensive Water Management Program. The results of which will help inform the City’s future actions regarding water supply, including: • Creating a monitoring plan to track key variables affecting changes in water availability • Implementation of water supply projects and programs • Water conservation efforts • Planning for future water use restrictions This study evaluates possible changes to legal and physical water availability to the City over a 50-year planning period. This scenario planning is based on four municipal water demand scenarios and six hydrology scenarios downscaled from Global Climate Models (GCM) to the watersheds of interest, Maroon and Castle Creeks. The six hydrology scenarios were the same used in the 2012 Colorado River Water Availability Study (CRWAS) and intended to represent 80% of the variability of the available 112 models from CMIP3 (Coupled Model Inter- comparison Project). Changes in hydrology and municipal demands were evaluated using a monthly time-step model which simulates the City’s raw water system. This model was previously developed by ENARTECH/Grand River Consulting and estimates flow conditions at specific nodes on Castle and Maroon Creeks based on the various hydrology and demand inputs. This streamflow model was used to estimate when water supply deficits may occur and evaluate available tools to mitigate the potential shortages. P66 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 2 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT 2.0 BACKGROUND The City’s potable water supply is primarily sourced from senior water rights which divert from both Castle Creek and Maroon Creek. As shown in Figure 1, water is diverted from Castle Creek and Maroon Creek and conveyed in buried pipeline via gravity to Thomas Reservoir near the Water Treatment Plant. From there, the City provides pressurized raw water from Thomas Reservoir and conveys water for treatment and integration into the potable water system. The City owns and operates additional irrigation diversions downstream of the municipal intake on Castle Creek. These include the Holden, Si Johnson1, and Marolt Ditches. Pursuant to direction from City Council, all City owned diversion structures are operated to maintain decreed instream flows. In this study, potential future water supply deficits are defined to occur when Castle Creek or Maroon Creek streamflow is inadequate to both allow for needed water diversion and to protect decreed instream flows on Castle Creek and Maroon Creek downstream of the City’s diversion facilities. Junior instream flow (ISF) water rights are held by the Colorado Water Conservation Board (CWCB) on both Castle and Maroon Creeks and are used to inform City operations and ensure a sufficient amount of water remains in the stream for environmental purposes. The decreed ISF on Castle Creek is 12.0 cfs, however for the purposes of this study we have increased the minimum bypass to 13.3 cfs. The City has deemed the higher amount more appropriate for the fishery and stream habitat and is in-line with current City diversion policies. This analysis assumes that 13.3 cfs is maintained below the Marolt Ditch head gate, which is the most downstream City owned diversion structure on Castle Creek. The Maroon Creek ISF is decreed at 14.0 cfs, and is maintained below the Maroon Creek Intake. The City does not currently divert water below this location on Maroon Creek. The City’s potable supply is largely dependent upon streamflow conditions of Maroon Creek and Castle Creek as no significant storage has been developed in the system. Thomas Reservoir is primarily used as a retention/stilling pond to regulate diversions before the water is conveyed to the water treatment plant and has a limited capacity of approximately 10 acre-feet (AF). Therefore, it is important to understand how streamflow conditions may change in relation to anticipated demands. Note, we understand the City is in the process of developing a new well system to help supplement its water supplies. 1 Si Johnson Ditch is currently managed by a Ditch Company, of which the City holds more than 75% interest. City staff currently operates the ditch on behalf of the company. P67 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 3 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT Figure 1: City of Aspen Municipal Water Supply System P68 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 4 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT 3.0 METHODS Below is a description of how the four demand and six hydrology scenarios were developed as inputs into the monthly streamflow model. 3.1 DEMAND SCENARIOS Four scenarios were developed to describe municipal water demands for the 50-year planning period. The goal of these demand scenarios is to represent a range of potential municipal water use that may develop within the study period. The scenarios include future demands that range from a no-growth scenario to a maximum annual growth rate of 1.8%. In each of the scenarios, the non-potable water sourced from Thomas Reservoir and irrigation ditch demands remain constant and were rounded to the nearest tenth of a cfs. This water is used to provide a supply for irrigation and snowmaking uses. Water used for snowmaking and irrigation within these categories is independent of population increases. Based on discussions with City managers it is understood that water used for these specific purposes is expected to remain constant over the next 50-year period, and therefore these uses do not change between demand scenarios. Future operations of non-City owned water rights on Maroon Creek are unknown at this time. All major Castle Creek diversions on are incorporated in the streamflow model. The City may use existing wells located within City limits to pump groundwater from the Roaring Fork alluvium. This water can be blended with surface water and incorporated into the treated municipal water supply. We have assumed that these well diversions will increase at the same rate as demand for treated water increases. Accordingly, the City well demands shown below increase between scenarios. 3.1.1 Demand Scenario 1A – Existing Baseline Demand This scenario represents the existing municipal water demands of the City. It is based on historical diversion data collected by the City from water year 2012 which was assessed against other recent year diversion data and determined to be most representative of current demand conditions. 2012 data is assumed to be more representative because drought induced water restrictions were implemented in water year 2013 and resulted in lower than typical water demands. Demand data was not available for the year 2014 to present at the time of this evaluation. Table 1 below shows average monthly water demands of scenario 1A by source and use type. P69 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 5 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT 3.1.2 Demand Scenario 2A – Historical Growth Rate of 1.2% This scenario represents municipal water demands for water at the end of the 50-year planning period, year 2064, calculated based on an annual growth rate of 1.2% from current conditions. This rate was estimated based on the historical 20-year average growth rate of new water users in the City. This rate is believed to be reasonable for planning purposes. Note that the 1.2% annual increase was only applied to treated water demands (indoor and outdoor). Non-potable and irrigation ditch demands were assumed to remain constant within the 50-year study period. Table 2 shows average monthly water demands of scenario 2A by use type. 3.1.3 Demand Scenario 2B – Restricted Development This scenario represents municipal water demands at the end of the 50-year planning period, year 2064, and was calculated based on an annual growth rate of 1.2% from current conditions. Irrigation Ditch Demands Indoor Outdoor Daily Use Peak 10 Day January 3.1 0.0 3.09 2.0 MGD 0.0 3.1 3.3 0.2 0.0 3.3 February 3.3 0.0 3.25 2.1 MGD 0.0 3.3 3.6 0.2 0.0 3.5 March 3.1 0.0 3.14 2.0 MGD 0.0 3.1 3.4 0.2 0.0 3.4 April 3.0 0.0 2.96 1.9 MGD 0.0 3.0 3.6 0.2 0.0 3.2 May 3.2 3.1 6.32 4.1 MGD 0.0 6.3 7.4 0.2 6.8 13.4 June 3.2 6.2 9.40 6.1 MGD 0.1 9.5 10.7 0.2 20.5 30.2 July 3.2 5.2 8.41 5.4 MGD 0.1 8.5 9.6 0.3 16.1 24.8 August 3.2 3.4 6.60 4.3 MGD 0.0 6.6 7.2 0.3 15.4 22.4 September 3.2 2.0 5.23 3.4 MGD 0.3 5.5 6.2 0.3 12.2 18.1 October 2.4 0.0 2.38 1.5 MGD 0.1 2.5 3.4 0.3 11.0 13.8 November 3.2 0.0 3.20 2.1 MGD 0.4 3.6 5.2 0.3 0.0 3.9 December 3.4 0.0 3.38 2.2 MGD 0.2 3.6 5.5 0.3 0.0 3.9 1Includes Holden Ditch, Marolt Ditch, and Si Johnson Ditch. Castle Creek1 Sub-Total City Well Demands Total Treated Water Non- Potable Sub-Total Month Thomas Reservoir Demands TABLE 1 City of Aspen Average Monthly Water Demands (cfs) SCENARIO 1A (Existing Baseline Demand) Irrigation Ditch Demands Indoor Outdoor Daily Use Peak 10 Day January 5.6 0.0 5.6 3.6 MGD 0.0 5.6 6.0 0.4 0.0 6.0 February 5.9 0.0 5.9 3.8 MGD 0.0 5.9 6.6 0.4 0.0 6.3 March 5.7 0.0 5.7 3.7 MGD 0.0 5.7 6.1 0.4 0.0 6.1 April 5.4 0.0 5.4 3.5 MGD 0.0 5.4 6.5 0.4 0.0 5.8 May 5.8 5.6 11.5 7.4 MGD 0.0 11.5 13.5 0.4 6.8 18.7 June 5.8 11.2 17.1 11.0 MGD 0.1 17.1 19.4 0.4 20.5 38.0 July 5.8 9.4 15.3 9.9 MGD 0.1 15.3 17.3 0.5 16.1 31.9 August 5.8 6.2 12.0 7.7 MGD 0.0 12.0 13.1 0.6 15.4 28.0 September 5.8 3.7 9.5 6.1 MGD 0.3 9.8 11.0 0.6 12.2 22.6 October 4.3 0.0 4.3 2.8 MGD 0.1 4.4 6.1 0.6 11.0 16.0 November 5.8 0.0 5.8 3.8 MGD 0.4 6.2 9.0 0.5 0.0 6.8 December 6.1 0.0 6.1 4.0 MGD 0.2 6.4 9.7 0.5 0.0 6.8 1Includes Holden Ditch, Marolt Ditch, and Si Johnson Ditch. Sub-Total GROWTH SCENARIO No. 2A (Historical Growth Rate 1.2%) Month Thomas Reservoir Demands City Well Demands Total Treated Water Non- Potable Sub-Total Castle Creek1 TABLE 2 Estimated City of Aspen Average Monthly Water Demands Year 2064 (cfs) P70 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 6 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT However, this scenario differs from scenario 2A in that treated outdoor water use by new water users located outside the existing City service area is prohibited. Records maintained by the City indicate that of the recent growth in water users, approximately 45% has historically occurred outside of the existing City limits. The goal of this scenario was to reduce the growth of peak annual water demands which has historically occurred during the summertime irrigation season (June – August). Table 3 shows average monthly water demands of scenario 2B by use type. 3.1.4 Demand Scenario 3A – CO State Demographer Growth Rate of 1.8% This scenario represents municipal water demands at the end of the 50-year planning period, year 2064, and was calculated based on an annual growth rate of 1.8% from current conditions. This rate is equal to the projected annual growth for Pitkin County as calculated by the Colorado State Demographer. This rate is believed to be the maximum realistic growth rate for the City and appropriate for planning purposes. Please note the 1.8% annual increase was only applied to treated water demands (indoor and outdoor). Non-potable and irrigation ditch demands were assumed to remain constant within the 50-year study period. Table 4 shows average monthly water demands of scenario 3A by use type. Irrigation Ditch Demands Indoor Outdoor Daily Use Peak 10 Day January 5.6 0.0 5.6 3.6 MGD 0.0 5.6 6.0 0.4 0.0 6.0 February 5.9 0.0 5.9 3.8 MGD 0.0 5.9 6.6 0.4 0.0 6.3 March 5.7 0.0 5.7 3.7 MGD 0.0 5.7 6.1 0.4 0.0 6.1 April 5.4 0.0 5.4 3.5 MGD 0.0 5.4 6.5 0.4 0.0 5.8 May 5.8 4.5 10.3 6.7 MGD 0.0 10.4 12.2 0.4 6.8 17.6 June 5.8 9.0 14.8 9.6 MGD 0.1 14.9 16.8 0.4 20.5 35.8 July 5.8 7.5 13.4 8.6 MGD 0.1 13.4 15.2 0.5 16.1 30.0 August 5.8 4.9 10.7 6.9 MGD 0.0 10.8 11.7 0.6 15.4 26.8 September 5.8 2.9 8.8 5.7 MGD 0.3 9.1 10.2 0.6 12.2 21.9 October 4.3 0.0 4.3 2.8 MGD 0.1 4.4 6.1 0.6 11.0 16.0 November 5.8 0.0 5.8 3.8 MGD 0.4 6.2 9.0 0.5 0.0 6.8 December 6.1 0.0 6.1 4.0 MGD 0.2 6.4 9.7 0.5 0.0 6.8 1Includes Holden Ditch, Marolt Ditch, and Si Johnson Ditch. 2Treated water demands grow at 1.2%, however 45 % of new growth is estimated to occur beyond existing service area and in these areas will exclude outdoor uses. Treated Water2 Non- Potable Sub-Total Castle Creek1 Sub-Total TABLE 3 Estimated City of Aspen Average Monthly Water Demands Year 2064 (cfs) GROWTH SCENARIO No. 2B (Restricted Development Scenario ) Month Thomas Reservoir Demands City Well Demands Total P71 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 7 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT We understand City water demands are dynamic and water operators must respond to instantaneous needs including fire protection and peak occupancy rates within the City. However, for the purposes of this study average monthly water demands were used in the model. The primary reason for this was the data limitation of future streamflow regimes. As mentioned above, data from the CRWAS study was utilized for future hydrology regimes. Data from this study was available on a monthly time step. To avoid introducing additional error into this study from downscaling the data to a daily time step, monthly data were used in order to have more confidence in the results. For this study, future demands were evaluated using the same temporal distribution as they have occurred historically. No effort was made to adjust demands earlier in the season in association with the projected earlier peak in snowmelt runoff because it is beyond the scope of this study to predict how those changes may occur. Historically, peak water use (excluding irrigation purposes) has occurred when occupancy is maximized within the City. One primary factor in occupancy is the time of year when tourists are mostly likely on vacation (summer, holidays, etc.) which is assumed to remain the same and is likely independent of potential changes in the climate. 3.2 HYDROLOGY SCENARIOS Each of the above mentioned demand scenarios were evaluated against six separate hydrology scenarios. These six scenarios include five Coupled Model Inter-comparison Project 3 (CMIP3) model runs which were utilized in the Colorado Water Conservation Board’s Colorado River Water Availability Study (CRWAS) published in March of 2012. The sixth scenario was the historic gaged hydrology on Castle and Maroon Creeks (1970-1994). The five CMIP3 scenarios were deliberately chosen out of the available 112 projections in order to represent 80% of the full range of modeled change in streamflow. Table 5 provides information on the change in precipitation, temperature and streamflow for each of the CMIP3 model scenarios. In addition, the percent change in streamflow, as compared to historical hydrology, is also included in the Irrigation Ditch Demands Indoor Outdoor Daily Use Peak 10 Day January 7.5 0.0 7.5 4.9 MGD 0.0 7.5 8.1 0.5 0.0 8.0 February 7.9 0.0 7.9 5.1 MGD 0.0 7.9 8.8 0.6 0.0 8.5 March 7.7 0.0 7.7 4.9 MGD 0.0 7.7 8.2 0.6 0.0 8.2 April 7.2 0.0 7.2 4.7 MGD 0.0 7.2 8.8 0.6 0.0 7.8 May 7.8 7.6 15.4 10.0 MGD 0.0 15.4 18.1 0.5 6.8 22.8 June 7.8 15.1 22.9 14.8 MGD 0.1 23.0 26.1 0.5 20.5 44.0 July 7.8 12.7 20.5 13.3 MGD 0.1 20.6 23.3 0.6 16.1 37.3 August 7.8 8.3 16.1 10.4 MGD 0.0 16.1 17.6 0.9 15.4 32.4 September 7.8 4.9 12.8 8.2 MGD 0.3 13.1 14.7 0.8 12.2 26.1 October 5.8 0.0 5.8 3.8 MGD 0.1 5.9 8.2 0.8 11.0 17.7 November 7.8 0.0 7.8 5.1 MGD 0.4 8.2 11.9 0.7 0.0 9.0 December 8.2 0.0 8.2 5.3 MGD 0.2 8.5 12.9 0.6 0.0 9.1 1Includes Holden Ditch, Marolt Ditch, and Si Johnson Ditch. Sub-Total Castle Creek1 Sub-Total TABLE 4 Estimated City of Aspen Average Monthly Water Demands Year 2064 (cfs) GROWTH SCENARIO No. 3A (CO State Demographer Growth Rate 1.8%) Month Thomas Reservoir Demands City Well Demands Total Treated Water Non- Potable P72 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 8 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT table for: Colorado River at Glenwood Springs, Roaring Fork River Near Aspen, and Castle and Maroon Creeks Above Aspen. Table 5: CMIP 3 Model Scenario Statistics relating to: precipitation, temperature and percent change in streamflow. CMIP3 Run % Change Precipitation Change Temperature (⁰C) Colorado River at Glenwood Springs % Change in Streamflow Roaring Fork River Near Aspen % Change in Streamflow Castle Creek Above Aspen % Change in Streamflow Maroon Creek Above Aspen % Change in Streamflow Scenario Identifier 4 -4% 4.5 -24% -8% -8% -9% Very Hot/Very Dry 53 -1% 3.6 -13% -12% -16% -19% Warm/Slightly Dry 51 1% 3.7 -8% -3% -8% -13% Warm/Slightly Wet 13 3% 2.3 1% 2% 0% -2% Warm/Wet 12 11% 3.7 13% 16% 9% 2% Warm/Very Wet Output from the CMIP3 models needed to be downscaled using the VIC (Variable Infiltration Capacity) model in order to obtain the hydrology at nodes that were not modeled explicitly in the CMIP3 climate models. A dataset was available for the Roaring Fork river near Aspen stream gage site (Figure 1). Note, methods used to downscale the CMIP3 data to the watersheds of interest was beyond the scope of this report, but can be found in the documentation of the CRWAS available through the Colorado Water Conservation Board. Using the monthly ratio of streamflow of Maroon and Castle Creeks to the Roaring Fork river, the climate scenario time series were developed for both Maroon and Castle Creeks at the location of the inactive USGS gage sites (Figure 1). This was done by using the VIC modeled output for the Roaring Fork and scaled using the relationships of Maroon and Castle creeks for each climate scenario. Figure 2 below shows how the average monthly hydrology of Maroon Creek changes with each climate scenario run and how it compares to the historic hydrology. One point to note is that the “identifier” given to each CMIP3 model run relates to the climate model forcing data: temperature and precipitation. Within this model, the relationship between the climate forcing factors and streamflow is not one to one, but rather varies based on many interrelated variables. In general, warmer climate scenarios tend to have an earlier start to the melt season than historical hydrology, but that is not always the case. As seen in Table 5, the same general trends are maintained between the four watersheds shown under the given climate scenarios, however percent changes in average monthly streamflow do vary. These differences between watersheds illustrate the difficulty of reducing large-scale climate model information to smaller watershed areas with complex topography. Efforts were made to ensure the downscaled hydrology on Maroon and Castle creeks followed the same trends as the nodes further downstream. P73 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 9 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT Figure 2: Maroon Creek average monthly streamflow for historical hydrology and the 5 CMIP3 model runs. The non-irrigation season is highlighted in blue. Streamflow is averaged by month and represents variability in hydrology during the 25-year study period. 3.3 STREAMFLOW MODEL ASSUMPTIONS Average monthly streamflow of Castle Creek and Maroon Creek was estimated as described above at the inactive USGS gage sites for each of the six hydrology scenarios. This information was then used in the streamflow tool to estimate flow at specific nodes shown in Figure 1. Streamflow was estimated at the Maroon Creek and Castle Creek intake structures based on a linear regression between flow at the inactive gage sites and the two intake locations. This regression is based on previous assessments carried out by ENARTECH and Grand River Consulting, including paired streamflow measurements. No consumptive use was assumed to occur between the Castle Creek gage site and the Castle Creek intake structure. However, on Maroon Creek the Herrick Ditch can divert significant quantities of water in the reach between the inactive Maroon Creek gage and Maroon Creek Intake structure. Because the City water rights are senior in priority to all but 9.3 cfs of the Herrick Ditch water rights, it was assumed that during low flow periods, the Herrick Ditch would only divert 9.3 cfs of native flow otherwise available at the Maroon Creek Intake structure. Streamflow at locations downstream of the City intake structures, as shown in Figure 1, were calculated in the model based on specific water demand and inflow criteria to replicate on the ground operations. P74 II. City of Aspen Water Supply Availability Study Wilson Water Group, March 2016 Page | 10 4.0 RESULTS Results for the four potential water demands and six potential hydrology scenarios are shown in Table 6 below. These results show the most severe single year ISF deficits for each scenario during the 25-year study period and are outlined by irrigation (May (Nov-Apr) seasons. Based on this analysis, significant ISF deficits have the in only the highest demand under warm and slightly dry conditions. Some of the drier climate scenarios do not result in significant deficits, which is in part due to the change in the timing of runoff realized from changes in temperat combinations, 16 show no or minor and easily mitigated, ISF deficits. However, seven combinations show ISF deficits greater than 200 acre irrigation season ISF deficits of about 600 AF. ISF deficits which have the potential to occur on Castle Creek and Maroon Creek within the 50 year planning window were calculated by demand scenario. The ISF deficits are shown in two ways (1) the percent of years a shortage may occur (frequency) over th period (1969-1994) and at what seasonal magnitude (AF), and (2) the maximum daily deficit in cubic feet per second (cfs), which were converted to from monthly values. 4.1 DEMAND SCENARIO 1A – EXISTING Two of the six hydrology scenarios show an ISF deficit for Demand Scenario 1A during the irrigation season. CMIP3 Run 53 and Run 51 show modest deficits occurring in about 5% of the years. The maximum daily ISF deficits were approximately 1.7 cfs in the late irrigation seaso Figure 3a and Figure 3b below show the maximum irrigation season deficits graphically. Non-irrigation season deficits occurred in two of the six hydrology scenarios, CMIP3 Run 4 and Run 53. These minimal deficits occur at a frequency of about 5% of the years and amounted to approximately 33 acre feet during the month of February in Run 4. maximum daily deficit of about 0.6 cfs. Figure 3c through Figure 3d below depict maximum modeled ISF deficits during the non City of Aspen Water Supply Availability Study – 2016 Update , March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 718 Cooper Ave, Glenwood Springs, CO 81601 Results for the four potential water demands and six potential hydrology scenarios are shown below. These results show the most severe single year ISF deficits for each scenario year study period and are outlined by irrigation (May-Oct) and non Apr) seasons. Based on this analysis, significant ISF deficits have the potential to develop in only the highest demand under warm and slightly dry conditions. Some of the drier climate scenarios do not result in significant deficits, which is in part due to the change in the timing of runoff realized from changes in temperature and precipitation. Of the 24 modeled combinations, 16 show no or minor and easily mitigated, ISF deficits. However, seven combinations show ISF deficits greater than 200 acre-feet (AF), and one is simulated to develop about 600 AF. ISF deficits which have the potential to occur on Castle Creek and Maroon Creek within the 50 year planning window were calculated by demand scenario. The ISF deficits are shown in two ways (1) the percent of years a shortage may occur (frequency) over the gaged hydrology 1994) and at what seasonal magnitude (AF), and (2) the maximum daily deficit in cubic feet per second (cfs), which were converted to from monthly values. XISTING BASELINE DEMAND ogy scenarios show an ISF deficit for Demand Scenario 1A during the irrigation season. CMIP3 Run 53 and Run 51 show modest deficits occurring in about 5% of the years. The maximum daily ISF deficits were approximately 1.7 cfs in the late irrigation seaso Figure 3a and Figure 3b below show the maximum irrigation season deficits graphically. irrigation season deficits occurred in two of the six hydrology scenarios, CMIP3 Run 4 and Run 53. These minimal deficits occur at a frequency of about 5% of the years and amounted to approximately 33 acre feet during the month of February in Run 4. This equates to an average maximum daily deficit of about 0.6 cfs. Figure 3c through Figure 3d below depict maximum modeled ISF deficits during the non-irrigation season graphically. Lakewood, CO 80228 Ave, Glenwood Springs, CO 81601 DRAFT Results for the four potential water demands and six potential hydrology scenarios are shown below. These results show the most severe single year ISF deficits for each scenario Oct) and non-irrigation potential to develop in only the highest demand under warm and slightly dry conditions. Some of the drier climate scenarios do not result in significant deficits, which is in part due to the change in the timing of ure and precipitation. Of the 24 modeled combinations, 16 show no or minor and easily mitigated, ISF deficits. However, seven feet (AF), and one is simulated to develop ISF deficits which have the potential to occur on Castle Creek and Maroon Creek within the 50- year planning window were calculated by demand scenario. The ISF deficits are shown in two e gaged hydrology 1994) and at what seasonal magnitude (AF), and (2) the maximum daily deficit in ogy scenarios show an ISF deficit for Demand Scenario 1A during the irrigation season. CMIP3 Run 53 and Run 51 show modest deficits occurring in about 5% of the years. The maximum daily ISF deficits were approximately 1.7 cfs in the late irrigation season. Figure 3a and Figure 3b below show the maximum irrigation season deficits graphically. irrigation season deficits occurred in two of the six hydrology scenarios, CMIP3 Run 4 and Run 53. These minimal deficits occur at a frequency of about 5% of the years and amounted to This equates to an average maximum daily deficit of about 0.6 cfs. Figure 3c through Figure 3d below depict maximum P75 II. City of Aspen Water Supply Availability Study Wilson Water Group, March 2016 Page | 11 Figure 3: Demand Scenario 1A Irrigation a 4.2 DEMAND SCENARIO 2A – HISTORICAL Three of the six hydrology scenarios show an ISF deficit for Demand Scenario 2A during the irrigation season. CMIP3 Run 53 and Run 51 show irrigation season deficits acre feet occurring in ~5% of the years, and lesser deficits occurring about 12% of the years. CMIP3 Run 12 show irrigation season deficits of about 100 acre feet occurring at the 5% frequency. CMIP3 Run 53 and CMIP3 Run 51 show maximum range from 4.3 cfs to 5.7 cfs during the month of September, while CMIP3 Run 12 has a deficit of about 1.9 cfs. Figure 4a and Figure 4b below show these results for the irrigation season graphically. Non-irrigation season deficits are present for five of the six hydrology scenarios. Maximum deficits for CMIP3 Run 53 and Run 4 exceed 300 acre feet in approximately 5% of the years studied, while smaller deficits may occur in up to 12% of the years. CMIP3 Run 51 shows a maximum deficit of 150 acre feet occurring 5% of the time. CMIP3 Run 13, and Run 12 show maximum ISF deficits of about 25 acre feet occurring 5% of the time. For each of the three climate scenarios showing ISF deficits, non about 0.3 cfs to 3.1 cfs. Figure 4c and Figure 4d below show these results graphically. City of Aspen Water Supply Availability Study – 2016 Update , March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 718 Cooper Ave, Glenwood Springs, CO 81601 : Demand Scenario 1A Irrigation and Non-irrigation season ISF deficits. ISTORICAL GROWTH RATE 1.2% Three of the six hydrology scenarios show an ISF deficit for Demand Scenario 2A during the irrigation season. CMIP3 Run 53 and Run 51 show irrigation season deficits up to about 300 acre feet occurring in ~5% of the years, and lesser deficits occurring about 12% of the years. CMIP3 Run 12 show irrigation season deficits of about 100 acre feet occurring at the 5% frequency. CMIP3 Run 53 and CMIP3 Run 51 show maximum ISF deficits on a daily basis to range from 4.3 cfs to 5.7 cfs during the month of September, while CMIP3 Run 12 has a deficit of about 1.9 cfs. Figure 4a and Figure 4b below show these results for the irrigation season n deficits are present for five of the six hydrology scenarios. Maximum deficits for CMIP3 Run 53 and Run 4 exceed 300 acre feet in approximately 5% of the years studied, while smaller deficits may occur in up to 12% of the years. CMIP3 Run 51 shows a ximum deficit of 150 acre feet occurring 5% of the time. CMIP3 Run 13, and Run 12 show maximum ISF deficits of about 25 acre feet occurring 5% of the time. For each of the three climate scenarios showing ISF deficits, non-irrigation season maximum daily deficits range from about 0.3 cfs to 3.1 cfs. Figure 4c and Figure 4d below show these results graphically. Lakewood, CO 80228 Ave, Glenwood Springs, CO 81601 DRAFT Three of the six hydrology scenarios show an ISF deficit for Demand Scenario 2A during the up to about 300 acre feet occurring in ~5% of the years, and lesser deficits occurring about 12% of the years. CMIP3 Run 12 show irrigation season deficits of about 100 acre feet occurring at the 5% ISF deficits on a daily basis to range from 4.3 cfs to 5.7 cfs during the month of September, while CMIP3 Run 12 has a deficit of about 1.9 cfs. Figure 4a and Figure 4b below show these results for the irrigation season n deficits are present for five of the six hydrology scenarios. Maximum deficits for CMIP3 Run 53 and Run 4 exceed 300 acre feet in approximately 5% of the years studied, while smaller deficits may occur in up to 12% of the years. CMIP3 Run 51 shows a ximum deficit of 150 acre feet occurring 5% of the time. CMIP3 Run 13, and Run 12 show maximum ISF deficits of about 25 acre feet occurring 5% of the time. For each of the three deficits range from about 0.3 cfs to 3.1 cfs. Figure 4c and Figure 4d below show these results graphically. P76 II. City of Aspen Water Supply Availability Study Wilson Water Group, March 2016 Page | 12 Figure 4: Demand Scenario 2A Irrigation and Non 4.3 DEMAND SCENARIO 2B – RESTRICTED As with Demand Scenario 2A, Demand Scenario 2B shows three of the six hydrology scenarios with an ISF deficit during the irrigation season. Because growth of outdoor water use was restricted in this demand scenario, we have modeled maximum deficits to e less than Demand Scenario 2A during the irrigation season. However, the frequency at which these deficits may occur remains the same at about 5% of the years. Maximum average daily ISF deficits range from about 1.2 cfs to about 5.0 cfs CMIP3 Run 51 deficits are about 3.6 cfs. Figure 5a and 5b below show these results graphically. Outdoor water use was varied only during the irrigation season between Scenario 2A and 2B, therefore non-irrigation season deficits for Demand Scenario 2B are equal to Demand Scenario 2A as shown below in Figures 5c City of Aspen Water Supply Availability Study – 2016 Update , March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 718 Cooper Ave, Glenwood Springs, CO 81601 : Demand Scenario 2A Irrigation and Non-Irrigation ISF deficits. ESTRICTED DEVELOPMENT As with Demand Scenario 2A, Demand Scenario 2B shows three of the six hydrology scenarios with an ISF deficit during the irrigation season. Because growth of outdoor water use was restricted in this demand scenario, we have modeled maximum deficits to equal 44 acre feet less than Demand Scenario 2A during the irrigation season. However, the frequency at which these deficits may occur remains the same at about 5% of the years. Maximum average daily ISF deficits range from about 1.2 cfs to about 5.0 cfs for CMIP3 Run 12 and CMIP Run 53, while CMIP3 Run 51 deficits are about 3.6 cfs. Figure 5a and 5b below show these results graphically. Outdoor water use was varied only during the irrigation season between Scenario 2A and 2B, ason deficits for Demand Scenario 2B are equal to Demand Scenario 2A as shown below in Figures 5c – 5d. Lakewood, CO 80228 Ave, Glenwood Springs, CO 81601 DRAFT As with Demand Scenario 2A, Demand Scenario 2B shows three of the six hydrology scenarios with an ISF deficit during the irrigation season. Because growth of outdoor water use was qual 44 acre feet less than Demand Scenario 2A during the irrigation season. However, the frequency at which these deficits may occur remains the same at about 5% of the years. Maximum average daily for CMIP3 Run 12 and CMIP Run 53, while CMIP3 Run 51 deficits are about 3.6 cfs. Figure 5a and 5b below show these results graphically. Outdoor water use was varied only during the irrigation season between Scenario 2A and 2B, ason deficits for Demand Scenario 2B are equal to Demand Scenario P77 II. City of Aspen Water Supply Availability Study Wilson Water Group, March 2016 Page | 13 Figure 5: Demand Scenario 2B Irrigation and Non 4.4 DEMAND SCENARIO 3A – CO Four of the six hydrology scenarios show an irrigation season deficit under Demand Scenario 3A. The most severe deficits occur at a frequency of 12% of the years under hydrology’s CMIP3 Run 53 and CMIP3 Run 51 and occur at levels of over 400 acre feet during the CMIP3 Run 12 has a maximum deficit of about 300 acre feet and CMIP3 Run 4 is less at 120 acre feet. Maximum average daily deficits are as much as 7.4 cfs and 8.8 cfs for CMIP3 Run 51 and CMIP3 Run 53 during late season. Figure 6a and Non-irrigation season ISF deficits for Demand Scenario 3A reach a maximum of about 750 acre feet for CMIP3 Run 4 with smaller deficits recorded in CMIP3 Runs 51, 12, 53 and 13. Two of the hydrology scenarios show minor deficits occurring in up to 23% of the years. Maximum average daily ISF deficits range from about 0.8 cfs to 5.1 cfs during the non all five CMIP3 hydrology scenarios. Figure 6c and Figure 6d below show these ISF deficits graphically. City of Aspen Water Supply Availability Study – 2016 Update , March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 718 Cooper Ave, Glenwood Springs, CO 81601 Figure 5: Demand Scenario 2B Irrigation and Non-Irrigation ISF deficits. CO STATE DEMOGRAPHER GROWTH RATE 1.8% the six hydrology scenarios show an irrigation season deficit under Demand Scenario 3A. The most severe deficits occur at a frequency of 12% of the years under hydrology’s CMIP3 Run 53 and CMIP3 Run 51 and occur at levels of over 400 acre feet during the irrigation season. CMIP3 Run 12 has a maximum deficit of about 300 acre feet and CMIP3 Run 4 is less at 120 acre feet. Maximum average daily deficits are as much as 7.4 cfs and 8.8 cfs for CMIP3 Run 51 and CMIP3 Run 53 during late season. Figure 6a and 6b below show these deficits graphically. irrigation season ISF deficits for Demand Scenario 3A reach a maximum of about 750 acre feet for CMIP3 Run 4 with smaller deficits recorded in CMIP3 Runs 51, 12, 53 and 13. Two of minor deficits occurring in up to 23% of the years. Maximum average daily ISF deficits range from about 0.8 cfs to 5.1 cfs during the non-irrigation season for all five CMIP3 hydrology scenarios. Figure 6c and Figure 6d below show these ISF deficits Lakewood, CO 80228 Ave, Glenwood Springs, CO 81601 DRAFT the six hydrology scenarios show an irrigation season deficit under Demand Scenario 3A. The most severe deficits occur at a frequency of 12% of the years under hydrology’s CMIP3 irrigation season. CMIP3 Run 12 has a maximum deficit of about 300 acre feet and CMIP3 Run 4 is less at 120 acre feet. Maximum average daily deficits are as much as 7.4 cfs and 8.8 cfs for CMIP3 Run 51 and 6b below show these deficits graphically. irrigation season ISF deficits for Demand Scenario 3A reach a maximum of about 750 acre feet for CMIP3 Run 4 with smaller deficits recorded in CMIP3 Runs 51, 12, 53 and 13. Two of minor deficits occurring in up to 23% of the years. Maximum irrigation season for all five CMIP3 hydrology scenarios. Figure 6c and Figure 6d below show these ISF deficits P78 II. City of Aspen Water Supply Availability Study Wilson Water Group, March 2016 Page | 14 Figure 5: Demand Scenario 3A Irrigation and Non 4.5 ALTERNATE HERRICK DITCH O Table 7 below shows the potential water supply deficits by season should the City be unable to place a valid water right call at the Maroon Creek Intake structure. This could potentially result in the Herrick Ditch diverting more than its senior 9.3 cfs w as assumed in the analysis described above. As such, this would reduce the amount of Maroon Creek water available for City use. This scenario assumes average monthly diversions by the Herrick Ditch increase from 9.3 cfs to a peak of 16.0 cfs during the month of July. This is based on user supplied diversion data from Herrick Ditch operators in recent years. At this time, it is unknown if this represents the maximum amount of water the Herrick Ditch may divert in t future. Water rights currently decreed to the Herrick Ditch total more than 64.0 cfs, however diversions are limited to the amount of water ditch users can put to legal beneficial use. This analysis represents the most water Herrick Ditch users have u in recent history. City of Aspen Water Supply Availability Study – 2016 Update , March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 718 Cooper Ave, Glenwood Springs, CO 81601 : Demand Scenario 3A Irrigation and Non-irrigation season ISF deficits. OPERATION, DEMAND SCENARIO 3A Table 7 below shows the potential water supply deficits by season should the City be unable to place a valid water right call at the Maroon Creek Intake structure. This could potentially result in the Herrick Ditch diverting more than its senior 9.3 cfs water right during critically dry years, as assumed in the analysis described above. As such, this would reduce the amount of Maroon Creek water available for City use. This scenario assumes average monthly diversions by the 3 cfs to a peak of 16.0 cfs during the month of July. This is based on user supplied diversion data from Herrick Ditch operators in recent years. At this time, it is unknown if this represents the maximum amount of water the Herrick Ditch may divert in t future. Water rights currently decreed to the Herrick Ditch total more than 64.0 cfs, however diversions are limited to the amount of water ditch users can put to legal beneficial use. This analysis represents the most water Herrick Ditch users have used on an average monthly basis Lakewood, CO 80228 Ave, Glenwood Springs, CO 81601 DRAFT Table 7 below shows the potential water supply deficits by season should the City be unable to place a valid water right call at the Maroon Creek Intake structure. This could potentially result ater right during critically dry years, as assumed in the analysis described above. As such, this would reduce the amount of Maroon Creek water available for City use. This scenario assumes average monthly diversions by the 3 cfs to a peak of 16.0 cfs during the month of July. This is based on user supplied diversion data from Herrick Ditch operators in recent years. At this time, it is unknown if this represents the maximum amount of water the Herrick Ditch may divert in the future. Water rights currently decreed to the Herrick Ditch total more than 64.0 cfs, however diversions are limited to the amount of water ditch users can put to legal beneficial use. This sed on an average monthly basis P79 II. City of Aspen Water Supply Availability Study Wilson Water Group, March 2016 Page | 15 Under this assumption, average monthly ISF deficits on Maroon Creek would increase from a maximum scenario (CMIP3 Run 53, Demand Scenario 3A) of 8.8 cfs as described above, to about 11.8 cfs during the irrigation season as shown below in Figure 7a and Figure 7b. Five of the six hydrology scenarios show an irrigation season deficit under the alternate Herrick Ditch operations and Demand Scenario 3A. The most severe deficits occur at a frequency of 15% of the years under hydrology CMIP3 Run 53 and CMIP3 Run 51 and occur at levels of about 1,300 acre feet during the irrigation season. CMIP3 Run 12 has a maximum deficit of about 700 acre feet and CMIP3 Run 4 is less at 400 acre feet. Maximum average da as 10.4 cfs and 11.8 cfs for CMIP3 Run 51 and CMIP3 Run 53 during late season. Figure 7a and 7b below show these deficits graphically. Note, non-irrigation season deficits for this scenario (Figure 7c and Figure 7d) do not change from the deficits described above in Section 4.4 above. City of Aspen Water Supply Availability Study – 2016 Update , March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 718 Cooper Ave, Glenwood Springs, CO 81601 Under this assumption, average monthly ISF deficits on Maroon Creek would increase from a maximum scenario (CMIP3 Run 53, Demand Scenario 3A) of 8.8 cfs as described above, to irrigation season as shown below in Figure 7a and Figure 7b. Five of the six hydrology scenarios show an irrigation season deficit under the alternate Herrick Ditch operations and Demand Scenario 3A. The most severe deficits occur at a frequency of % of the years under hydrology CMIP3 Run 53 and CMIP3 Run 51 and occur at levels of about 1,300 acre feet during the irrigation season. CMIP3 Run 12 has a maximum deficit of about 700 acre feet and CMIP3 Run 4 is less at 400 acre feet. Maximum average daily deficits are as much as 10.4 cfs and 11.8 cfs for CMIP3 Run 51 and CMIP3 Run 53 during late season. Figure 7a and 7b below show these deficits graphically. irrigation season deficits for this scenario (Figure 7c and Figure 7d) do not change from the deficits described above in Section 4.4 above. Lakewood, CO 80228 Ave, Glenwood Springs, CO 81601 DRAFT Under this assumption, average monthly ISF deficits on Maroon Creek would increase from a maximum scenario (CMIP3 Run 53, Demand Scenario 3A) of 8.8 cfs as described above, to irrigation season as shown below in Figure 7a and Figure 7b. Five of the six hydrology scenarios show an irrigation season deficit under the alternate Herrick Ditch operations and Demand Scenario 3A. The most severe deficits occur at a frequency of % of the years under hydrology CMIP3 Run 53 and CMIP3 Run 51 and occur at levels of about 1,300 acre feet during the irrigation season. CMIP3 Run 12 has a maximum deficit of about 700 ily deficits are as much as 10.4 cfs and 11.8 cfs for CMIP3 Run 51 and CMIP3 Run 53 during late season. Figure 7a and irrigation season deficits for this scenario (Figure 7c and Figure 7d) do not change P80 II. City of Aspen Water Supply Availability Study Wilson Water Group, March 2016 Page | 16 Figure 7: Demand Scenario 3A: Alternate Herrick Ditch Operations with Irrigation and Non 5.0 ALTERNATE WATER SUPP All ISF deficits which may develop in the 50 drought contingency planning that the City already has in place. The section below will describe those mitigation tools currently available to the City (or plann implemented in each of the demand scenarios described above. 5.1 ALTERNATE WATER SUPPLY O 5.1.1 Wastewater Reuse Program The City is diligently working towards bringing this program online. The City plans to pump treated wastewater from the Aspen Water and Sanitation District water treatment plant located near the confluence of Maroon Creek and the Roaring Fork River up to the City golf course. From here this water can be re wintertime snowmaking. Under full application, this program can physically supply up to 3.0 cfs of the non-potable irrigation water demands. During the non can supply all non-potable snowmaking demands which average about 0.3 cfs dur and December. City of Aspen Water Supply Availability Study – 2016 Update , March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 718 Cooper Ave, Glenwood Springs, CO 81601 Figure 7: Demand Scenario 3A: Alternate Herrick Ditch Operations with Irrigation and Non-irrigation season ISF deficits ALTERNATE WATER SUPPLIES AND THEIR POTENTIAL IMPLEMENTATION All ISF deficits which may develop in the 50-year planning horizon can likely be mitigated by drought contingency planning that the City already has in place. The section below will describe those mitigation tools currently available to the City (or planned) and how they can be implemented in each of the demand scenarios described above. OPTIONS Wastewater Reuse Program The City is diligently working towards bringing this program online. The City plans to pump er from the Aspen Water and Sanitation District water treatment plant located near the confluence of Maroon Creek and the Roaring Fork River up to the City golf course. From here this water can be re-used for non-potable irrigation demands and snowmaking. Under full application, this program can physically supply up to 3.0 cfs potable irrigation water demands. During the non-irrigation season, this program potable snowmaking demands which average about 0.3 cfs dur Lakewood, CO 80228 Ave, Glenwood Springs, CO 81601 DRAFT irrigation season ISF deficits TIAL IMPLEMENTATION year planning horizon can likely be mitigated by drought contingency planning that the City already has in place. The section below will ed) and how they can be The City is diligently working towards bringing this program online. The City plans to pump er from the Aspen Water and Sanitation District water treatment plant located near the confluence of Maroon Creek and the Roaring Fork River up to the City golf potable irrigation demands and snowmaking. Under full application, this program can physically supply up to 3.0 cfs irrigation season, this program potable snowmaking demands which average about 0.3 cfs during November P81 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 17 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT 5.1.2 Water Restrictions (Potable and Non-Potable Water Uses) The City has adopted revised drought restrictions as of fall of 2015. Restrictions are implemented via action by the City Council and are aimed at all City water users. These restrictions are divided into three stages and vary by water source with specific target reductions. The restriction levels are shown below in Table 8. Table 8: City of Aspen Water Restriction Stages and Water Savings Target Treated Water General Raw Water (Thomas Line) Raw Water (Ditches) Stage 1 10.0% 10.0% 10.0% Stage 2 15.0% 17.5% 20.0% Stage 3 20.0% 25.0% 30.0% In 2012 and 2013, the City implemented Stage 1 and 2 drought restrictions (prior to the 2015 water saving targets revisions). Stage 1 was successful in reducing demands by 10%, however when Stage 2 was implemented, water users did not reach the desired 20% demand reduction target. Table 8 above shows the revised restriction levels with Stage 2 reduced to 15% for treated water, 17.5% for raw pressurized water and 20% for raw water in ditches. In this analysis, it is assumed that under all climate scenarios, water users will reach the targeted reductions put forward by City Council. To the extent this cannot be accomplished, diversions from the City wells may be used to supply additional water to address any remaining deficit to the ISF. 5.1.3 Municipal Wells The City has in operation several shallow alluvial wells, which can be used to supplement municipal water demands. In addition, the City is in the process of developing a deep bedrock well which can also be used to supplement water demands during drought conditions. For the purposes of this assessment it is assumed that these wells have the potential to produce up to 5.0 cfs in combination. The wells can be operated to provide water supplies and reduce otherwise needed surface water diversions from Castle and Maroon Creeks. In this way, the City can ensure the ISFs on Castle Creek and Maroon Creek are satisfied. Water quality does present an issue in using alluvial well water for potable purposes because of Fluoride and Radionuclides (Uranium) contaminants. Because of these factors, the water must be blended with alternative sources of surface water or treated prior to use. The goal of the City over the 50-year planning period is to identify water supplies suitable for mixing to reduce the contaminant levels (i.e. deep bedrock well) or install a reverse osmosis system to treat the alluvial well water for use as a potable source. The shallow alluvium wells and deep bedrock well are tributary to the Roaring Fork River at a point upstream of the confluence of Castle Creek. Therefore, all well depletions will occur to P82 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 18 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT the Roaring Fork River. It should be noted, that during times of drought and ISF deficits on Castle and Maroon Creeks, similar conditions may also be present at this location within the Roaring Fork River. The City is planning additional investigations of the deep bedrock well to evaluate specific characteristics of this aquifer. At this time, the City anticipates water produced from this well may be of better quality than the shallower alluvium wells and may also have a significantly longer lag from time of pumping to the time when those depletions occur to the Roaring Fork River. However, regardless of whether the City relies more on the alluvial wells or deep bedrock wells, the net effect on Roaring Fork River streamflow should be considered prior to pumping water from wells during drought conditions. 5.2 IMPLEMENTATION OF ALTERNATE WATER SUPPLY OPTIONS An evaluation was conducted using the tools described above to mitigate the ISF deficits that were modeled in section 4.0. For simplicity, only the climate scenario that resulted in largest deficit will be addressed. 5.2.1 Demand Scenario 1A – Existing Baseline Demand Daily irrigation season ISF deficits occur during the month of September at a maximum rate of about 1.7 cfs. This ISF deficit can be addressed by implementing the City wastewater reuse program. Average daily non-irrigation season ISF deficits may occur at a rate of about 0.1 cfs during February. This deficit can be address with Stage 1 water restrictions (10% reduction of all water demands). 5.2.2 Demand Scenario 2A – Historical Growth Rate 1.2% Daily irrigation season ISF deficits occur during the months of August and September at a maximum rate of about 5.7 cfs. This ISF deficit can be addressed by implementing the City wastewater reuse program and initiating Stage 2 water restrictions (15% reduction of potable water demands and 20% reduction of ditch diversions). Non-irrigation season ISF deficits occur from December through March and reach a maximum of about 2.7 cfs in February. During these months, the Stage 2 City water restrictions can help to meet these deficits in combination with pumping well water at a total rate of about 2.2 cfs. 5.2.3 Demand Scenario 2B – Restricted Growth Daily irrigation season ISF deficits occur during the month of September at a maximum rate of about 5.0 cfs. This ISF deficit can be addressed by implementing City wastewater reuse program and initiating Stage 2 water restrictions. These restrictions would reduce potable water use by 15% and non-potable ditch demands by 20%. P83 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 19 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT 5.2.4 Demand Scenario 3A – CO State Demographer Growth Rate 1.8% Daily irrigation season ISF deficits occur during the months of July, August, September and October. The maximum deficits occur in September at a rate of about 8.0 cfs. This ISF deficit can be addressed by implementing the City wastewater reuse program and initiating Stage 3 water restrictions. These restrictions would reduce potable demand by 20% and non-potable ditch demands by 30%. Non-irrigation season ISF deficits occur from December through February and reach a maximum of about 4.6 cfs in February. In combination with Stage 3 water restrictions, municipal wells can supply about 3.5 cfs during the month of February to ensure ISFs are met. 5.2.5 Alternate Herrick Ditch Operation, Demand Scenario 3A Daily irrigation season ISF deficits occur during the months of July, August, September and October. The maximum deficits occur in September of critically dry years at a rate of 11.8 cfs. All but approximately 1.2 cfs can be mitigated via Stage 3 water restrictions, implementing the City wastewater reuse program and pumping the assumed maximum well diversion of 5.0 cfs. Additional water sources, or other reductions in water demands would be necessary under this scenario. 6.0 DISCUSSION The City balances available water supplies to provide potable water, raw water, and ensure ISFs are met. The results of this analysis indicate the City can always provide sufficient potable and raw water supplies under these modeled demand and hydrology scenarios. Existing water supply infrastructure and water rights portfolio developed and managed by the City do not appear to be limiting factors in this evaluation. However, during drought periods, physical water supplies may limit the City from satisfying desired ISF bypasses. These modeled ISF deficits are forecasted to occur during drought periods in only the climate scenarios with very low late summer and winter streamflow conditions. Most ISF deficits occur at a frequency of 5% of the time or 1 out of 20 years. The predicted average daily ISF deficits are relatively small and can be managed utilizing the existing water supply tools the City has in place and/or is actively developing. From the climate and hydrology scenarios evaluated, irrigation season deficits may be mitigated by implementing drought related water use restrictions and operating the City wastewater reuse program. Some scenarios in this analysis indicate that well pumping must be relied upon more heavily during the wintertime in order to ensure ISF rates are met. For the 50-year planning window, under the largest growth and driest climate scenario an average monthly ISF deficit of 3.5 cfs is possible, and could be satisfied by increased well pumping. However, as indicated above, these wells are tributary to the Roaring Fork River and may impact streamflow within a reach of the City upstream of the Castle Creek confluence. Depending on how future on-the-ground conditions develop, the City may study how delayed P84 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 20 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT depletions from specific wells -including the deep bedrock aquifer well- affects streamflow of the Roaring Fork River. The results of this study indicate that under historical hydrology conditions, water demands through the next 50 years can be met. However, under specific dry climate change scenarios, the City would be required to implement several tools to curtail water demands in order to fulfil the objectives of providing a reliable water supply for potable, raw, and ISF purposes. All of the water supply alternatives listed above are either in place currently or the City is actively working towards bringing them online. The 2000 ENARTECH Raw Water Availability report conclusions line up well with the findings of this analysis with respect to historical hydrology conditions, in that no significant deficits are predicted. However, the driest of the climate change hydrology scenarios suggest that water supplies from Castle Creek and Maroon Creek may result in infrequent deficits to the desired ISFs. However, initiating alternative water supply options can reduce projected demand and/or provide enough additional water supply to eliminate these deficits. This analysis has assumed that in dry years and during times of low streamflow, Herrick Ditch diversions will be curtailed to 9.3 cfs (the Herrick Ditch water right senior in priority to City owned Maroon Creek water rights). Under this assumption, all diversions by the Herrick Ditch junior priorities would be curtailed. As shown in Table 7 and Figure 7, if this were not the case and the Herrick Ditch were able to continue diverting at current rates during critically dry years, the City would experience additional water shortages. Water supply options such as water use restrictions, and wastewater reuse as described in this report may not be sufficient to cover all ISF deficits as modeled. 7.0 RECOMMENDATIONS The above mentioned strategies can help address ISF deficits simulated under all scenarios evaluated in this study. However, it is recommended that the City establish a long-term program to monitor regional hydrology moving forward. The monitoring program can help City managers recognize trends in both physical water availability and municipal demands. These observations can help inform future planning efforts and identify whether or not actual on the ground conditions are in-line with scenarios evaluated in this study. The study of climate change and specifically how streamflow responds to potential changes in precipitation and temperature are ever evolving. The hydrology scenarios represented here are intended to represent 80% of the range in potential outcomes over the next 50 years. However, it remains very difficult to accurately assess future conditions in the central Colorado mountains, specifically at the individual watershed level. Therefore, it is recommended that the City initiate a monitoring program to track changes in Castle Creek and Maroon Creek hydrology through time. In this way, specific indicators can be monitored and provide a record of how future water supplies and demands are changing from historical conditions. P85 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 21 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT It is recommended that the City prepare an annual report to document, summarize and evaluate current trends in water supply from historical data. This document would include the following parameters. 1. Date of peak snowpack measured at the Independence Pass and Schofield Pass SNOTEL sites. The federal Natural Resource Conservation Service (NRCS) currently manages several SNOTEL sites in the area where snowpack conditions are monitored. It is recommended that the City identify the date of peak snow pack conditions at both the Independence Pass and Schofield Pass SNOTEL sites, which are in close proximity to Castle Creek and Maroon Creek watershed areas. As such, these two SNOTEL sites should track closely with conditions in the two drainages. This information will be used to help inform when peak snowmelt runoff may occur and serve as an indicator to late summer streamflow. 2. Date of peak snowmelt runoff measured at the Maroon Creek and Castle Creek intake structures. It is recommended that the City begin monitoring streamflow at both Maroon Creek and Castle Creek intake structures. No streamflow gage currently exists at these locations; however, the City can estimate flow above the diversion structures by adding two measured flow values. The City currently measures the amount of water diverted from the stream at each of these intake structures. Additionally, the City has installed pressure transducers to understand the height of water, or stage, below the diversion dams. This stage data can be related to point flow measurements to develop stage discharge rating curves. The rating curves can be used to estimate streamflow that is bypassed down from the intake structures on a real time basis. By adding the bypass flow to the diversion, the City can estimate the total amount of flow in each creek at the respective intake structures. This information can be summarized to provide average daily streamflow, from which the date of peak snowmelt runoff can be recorded each year. Moreover, data from the bypass measurement will be important in critically dry periods when the City is concerned about ensuring water is bypassed at the respective ISF rates. 3. Monthly rainfall at the City Water Treatment Plant. Castle Creek and Maroon Creek are snowmelt dominated watersheds. However, rainfall events can have a major effect on streamflow in the late summer and fall time periods. It is recommended that daily rainfall recorded at the City Water Treatment Plant be summarized and documented. This information can be compared to historical information to understand if current trends differ from historical conditions. To date it has been very difficult to predict how climate change may affect summer rainfall patterns, so it is important the City maintains accurate records and understands if any trends appear to deviate from historical data. Raw water demands associated with irrigation are also directly linked to summer precipitation. If more rain falls in the area, then irrigation demands would be reduced. P86 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 22 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT Conversely, if less rain falls in the area then irrigation demands may rise above historical levels. 4. Diversions by other in-basin water users including the Herrick Ditch. Water users upstream from the City Intake structures in the Castle Creek and Maroon Creek watersheds have a direct effect on the amount of water available to the City. Currently, no significant water diversions exist upstream of the Castle Creek intake, however the Herrick Ditch is a major irrigation diversion located upstream of the Maroon Creek Intake. It’s important for the City to understand if future diversions by this structure significantly differ from historical operations. It is important to understand how these parameters may be changing over time, as well as how they compare with municipal demands. In addition to the water supply, it will also be important to monitor temporal changes in water demands (i.e. peak and duration of irrigation demands) and how they relate to the timing of available water supplies. Though this study did not evaluate this aspect, monitoring of future irrigation demands can help to recognize if changes in the timing/magnitude of such water demands remain in line with the timing of available water supplies. If at any point within the 50-year planning window City managers find that on-the-ground conditions, or projected forecasts are significantly different than the scenarios evaluated in this study, it may be beneficial for the city to update this analysis. Climate change science is evolving rapidly as is the computing power for running GCM’s with more detail. P87 II. City of Aspen Water Supply Availability Study – 2016 Update Wilson Water Group, March 2016 165 S Union Blvd, Ste 520, Lakewood, CO 80228 Page | 23 718 Cooper Ave, Glenwood Springs, CO 81601 DRAFT 8.0 REFERENCES Sheaffer & Roland, Inc. 1984. Raw Water Supply Update Comprehensive Water Management Plan City of Aspen. May. ENARTECH Inc. 1994. City of Aspen Evaluation of Raw Water Availability. October. ENARTECH Inc. 2000. City of Aspen Assessment of Raw Water Availability. April. AECOM. 2012. Colorado River Water Availability Study. March C:\Users\Max\Google Drive\City of Aspen\ScenarioPlanningAspen_2016-03-30.docx P88 II. Page 1 of 3 MEMORANDUM TO: Mayor and City Council FROM: Lee Ledesma, Utilities Finance & Admin Services Manager THRU: Dave Hornbacher, Director of Utilities & Environmental Initiatives Scott Miller, Public Works Director DATE OF MEMO: May 11, 2016 MEETING DATE: May 16, 2016 RE: 2016 Water Conservation Programs REQUEST OF COUNCIL: Participate in review of the 2016 Water Conservation programs and provide feedback and direction. PREVIOUS COUNCIL ACTION: In September of 2015, Council adopted two Water Efficiency Plans—Resolution 79 and 81—the Roaring Fork Watershed Regional Water Efficiency Plan and the Aspen Municipal Water Efficiency Plan. These plans were developed utilizing a grant from the Colorado Water Conservation Board (CWCB). During the presentation of these plans, the following Water Conservation programs were identified as outdoor water efficiency measures: • Landscaping regulations for new development, • Slow the Flow landscape water audits, • Garden-in-a-Box price buy-down, • Xeriscape educational seminars, • Conservation pricing, and • On-going customer education and information. BACKGROUND: The City has been implementing a water conservation plan since 1996. For the past two decades the City has shown a commitment to policies, practices and programs that extend water supplies and promote the responsible and efficient use of our water resources. DISCUSSION: Utilities and Environmental Initiatives agency staff met at the beginning of 2016 to discuss how best to utilize current funding for water conservation and efficiency programs. The following programs were chosen by the Water Conservation team. This team is made up of Ryland French, Karen McConnell, Kevin Pascal, Laura Armstrong, Tyler Christoff, Jane Wilch, and Lee Ledesma. The Water Conservation team reviewed 11 programs and selected the following based on what they determined best matched Aspen community values and long-range water savings goals: LivingWise Program – Cost $3,700 – The Living Wise program is a long running partnership with Holy Cross Energy and the Aspen School District providing energy and water efficiency curriculum and take home quick fix items, such as showerheads and light bulbs, to 5th graders in Aspen. The 2016 program has been a great success. We enrolled 108 this year, compared to 82 in 2015. The P89 III. Page 2 of 3 materials were shipped to the teacher on April 26th, so the schools should be wrapping up the program soon. The Program Summary report will be ready at the beginning of August with the final conservation results. Garden In A Box -- Cost $5,500 – All City of Aspen Water customers are being offered a low- water, perennial garden that features 28 altitude-loving plants that are pollinator-friendly. The full cost of each order is $144 but City of Aspen is providing a $25 buy-down, reducing the total cost to $119 for this professional designed, Colorado grown garden. These installations are designed to occupy the space of traditional decorative landscape treatments while significantly reducing irrigation use by the customer Slow the Flow Program – Cost $12,500 -- This program represents the City’s partnership with the Center for ReSource Conservation. In 2016 the City will be offering both indoor and outdoor water audits with the option of having a rain sensor installed if the customer participates in the outdoor irrigation water audit. The cost to the customer for both of these audits, as well as the rain sensor, is FREE. Pre Rinse Spray Valve (PRSV) Program -- Cost $4,500 – This program conserves water and helps restaurants save on their water bill. The program will be offered to 20 Aspen food establishments in 2016 and the assessments will take place from August 16th - 18th. Each restaurant will receive an assessment potentially a new PRSV, which entails a 5-minute swap where the existing PRSV is replaced with a high efficiency model that offers parallel or improved water pressure, while reducing the amount of water released. The cost to the customer is FREE. Water Loss Control – American Water Works Association (AWWA) M36 Technical Assistance Program -- Cost $10,000 (potential CWCB grant) -- Water loss control is the practice of system auditing, loss tracking, infrastructure maintenance, leak detection and leak repair for water utilities, and can be applied to both treated and raw water systems. As part of this Regional Water Efficiency Plan, technical assistance for completing the water audits using the AWWA M36 standardized method and establishing an annual audit is being pursued. City staff is working with CWCB to obtain a grant for training and technical assistance that would include the other four municipal water providers in the Roaring Fork Regional Water Efficiency Plan—Snowmass, Basalt, Carbondale and Glenwood Springs. Landscape Ordinance – Cost $15,000 (potential CWCB grant) -- As part of its Water Efficiency Plan update in 2015, Aspen Utilities identified the opportunity to achieve reasonable cost savings in reducing water demands through landscaping regulations for new development. This type of regulation is being considered throughout Colorado and provides an opportunity to reduce the impact from future demands by building smart from the start. Substantial amounts of water can be saved using existing technology. Utilities staff are working with the Colorado Water Conservation Board to obtain an implementation grant that would facilitate an inclusive process where the landscaping industry and other community members could contribute to developing a relevant and effective landscape ordinance. A kickoff meeting with internal staff is expected to occur in June with subsequent meetings being held throughout the summer and fall with landscape and property management professionals, as well as interested members of the Aspen community. Staff expects a completed draft ordinance for council review by early 2017. P90 III. Page 3 of 3 Certification Program Targeted at Property Managers and Landscaping Professionals -- Cost $10,000 (potential CWCB grant) -- Engaging the landscape industry through a certification program would further encourage creation and maintenance of water efficient landscapes through education, information, and potentially an awards program. Once a landscape ordinance is in place and being enforced, a certification program benefits professionals by educating them about the standards and criteria enforced under the regulation. It also provides credibility and helps professionals grow their business by letting their customers know that they can get the job done. The grant would allow staff to further advance this program concept. To date, the Roaring Fork Conservancy (RFC) has been working with Roaring Fork Leadership (RFL) on researching landscape certification programs elsewhere in the country with the objective of putting something similar in place here. The RFC and RFL team will be participating in the Landscape Ordinance kickoff and offering their ideas on how these two programs can be partnered. EPA WaterSense H2Otel Challenge -- Cost $1,500 in 2016; potential $15,000 Cost in 2017 -- The H2Otel Challenge encourages hotels to: assess water use and savings opportunities; change products or processes to incorporate best management practices; and track their water-saving progress and achievements. In the City of Aspen, including businesses, HOAs, and residential landscape categories in this type of program that publically rewards those who achieve water savings can help engage water users to incentivize and broaden the appeal of this challenge. This challenge has a proposed 2017 kickoff with the foundational work for its success being performed in 2016. The City of Aspen is a confirmed WaterSense partner and the EPA has been contacted for updated program information. Coordinated Public Outreach/Communication -- Cost $2,000 -- Branding with a recognizable image or slogan is useful for consistent messaging and engaging the public. A regional municipal water efficiency campaign could be implemented by Roaring Fork water providers alone, but would likely be more successful and less costly if implemented in partnership with local non-profits, businesses, schools, and other organizations. The new Colorado WaterWise campaign and toolkit “Live Like You Love It” was announced in October 2014 and should be considered further. The next meeting of Roaring Fork Watershed Regional Efficiency Plan representatives will be held Thursday, May 19th and branding and education will be part of the agenda and group discussion. FINANCIAL IMPACTS: 2016 Water Conservation program has a budget authority of $75,000. Approximately $64,700 of those funds have been outlined above as staff-identified 2016 Water Conservation programs ENVIRONMENTAL IMPACTS: The City of Aspen Water Utility has had a Water Conservation plan for 20 years. By using the term Water Conservation, staff refers to water use efficiency, wise water use, and water transmission and distribution system efficiency. The objective of the 2016 Water Conservation Programs is a long-term increase in the productive use of the city’s water supply in order to satisfy water supply needs without compromising desired water services. It is important to remember that the City of Aspen’s available water supply is not only affected by population growth and system demand; but, it is also affected by Aspen’s commitment to: (a) protect decreed instream flows; (b) the extent of our water conservation and efficiency programs; and, (c) water supply improvements outlined in the asset management plan. The Water Utility remains committed to its annual promotion of water conservation/efficiency programs and the pledge to protect the resources that makes Aspen the place we all love. CITY MANAGER COMMENTS: P91 III.