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HomeMy WebLinkAboutAppendix C. Exhibit 13 Trip Gen and Impacts MemoM EMORANDUM TO: Norway Island, LLC FROM: Todd Frisbie, PE, PTOE Associate, FHU DATE: December 3, 2018 SUBJECT: Gorsuch Haus Traffic Evaluation The memorandum is intended to provide an assessment of traffic related to the proposed Gorsuch Haus and the Lift One Lodge developments, including the proposed site planning for lift access and public parking. In this document is an assessment of the combined trip generation impacts of the two developments. Also presented, is an assessment of the difference in traffic on South Aspen Street south of Dean Street as a result of these two future developments. Summary Overview The combined new-vehicles trips added to intersections and roadways by both the Gorsuch Haus and the Lift One Lodge developments will not have a significant negative impact on traffic conditions in the area. South Aspen Street will experience a change in traffic volumes. The change will occur because traffic impacts of the Gorsuch Haus and Lift One Lodge operations is mitigated by the relocation of the existing Lift 1A drop-off / pickup area and available public parking from South Aspen Street to Dean Street. Gorsuch Haus Trip Generation The peak hour trip generation is a function of the traffic generated by the lodging and commercial components of the Gorsuch Haus. The trip generation estimates, per the City of Aspen’s traffic impact study guidelines, must be based on City of Aspen specific trip generation rates. Table 1 shows these City specific rates and the resulting trip generation estimate for the Gorsuch Haus. As shown, the peak hour trip generation for Gorsuch Haus is estimated at about 35 vehicle-trips in the AM peak hour and about 50 vehicle-trips in the PM peak hour. Appendix C. Exhibit 13 December 3, 2018 Gorsuch Haus Development Page 2 Table 1. Gorsuch Haus Trip Generation Estimate Proposed Land Use Size Trip Generation Rates Trips Generated AM Peak Hour PM Peak Hour AM PM Entering Exiting Total Entering Exiting Total % Trips Trips % Trips Trips Trips % Trips Trips % Trips Trips Trips Lodge Units 81 Units 0.25 0.31 57% 12 43% 9 21 52% 13 48% 12 25 Affordable Housing 1 Unit 0.67 0.82 48% 0 52% 1 1 55% 0 45% 1 1 Commercial 7,130 Leasable SF 2.27 4.14 69% 11 31% 5 16 40% 12 60% 18 30 Total Trip Generation Estimate 23 14 37 25 31 56 Internal Trip Reduction1 1 1 2 4 4 8 Total External Traffic Volumes 22 13 35 22 26 48 1 Internal trip reduction recognizes that hotel visitors and skiers will be commercial use customers and therefore would already be at the base area. To estimate internal reduction the following assumptions were used. AM peak hour 4% reduction per City of Aspen Traffic Impact Study Guidelines PM peak hour 14% reduction per City of Aspen Traffic Impact Study Guidelines Traffic Volume Impact Assessment In this effort we have focused on the peak hour volume impact to adjacent intersections. Tables 2 and 3 show the increase in peak hour traffic volumes to be added to adjacent intersections as a result of both the Gorsuch and Lift One Lodge developments. The average skier day is the average number of skier visits during the ski season while a peak skier day represents the highest number of skier visits. As shown in both Tables 2 and 3 the peak hour vehicle-trips are mostly attributed to the Lift One Lodge and mountain portal development. This is primarily due to the public parking and skier drop-off / pick-up area associated with the Lift One Lodge. 1 Of the intersections evaluated, the South Aspen Street intersections with Durant and Dean will experience much of the traffic generated by both the Gorsuch Haus and Life One Lodge developments. Table 2. Peak Hour Volume Impact to South Aspen Street Intersections – Average Skier Day Intersection Lift One Lodge Gorsuch Haus Total AM Peak PM Peak AM Peak PM Peak AM Peak PM Peak Durant / Aspen 47 98 31 43 78 141 Dean / Aspen 47 98 36 48 83 146 Table 3. Peak Hour Volume Impact South Aspen Street Intersections – Peak Skier Day Intersection Peak Hour – Average Day Gorsuch Haus Total AM Peak PM Peak AM Peak PM Peak AM Peak PM Peak Durant / Aspen 70 146 31 43 101 189 Dean / Aspen 70 146 36 48 106 194 1 ASC projects that the lower lift location at Dean Street and the proposed improvements to the Lift One Mountain Portal will increase the number of skiers that begin their day [initial scans] at this portal to 20%. Currently, approximately 3% of skiers on Aspen Mountain begin their day at Lift 1A. December 3, 2018 Gorsuch Haus Development Page 3 Given the location of these intersections relative to the City of Aspen, the overall traffic at these intersections prior to the development of these lodges is likely to be relatively low. Plus, the additional peak hour trips generated by the proposed development are not significantly high numbers. Given these two factors, the existing stop-controlled intersections listed in Table 4 likely have enough excess capacity to accommodate the increase in traffic without causing a significant increase in delay. In addition, intersection safety can be a concern when traffic volumes approach capacity. Since these intersections likely have excess capacity to accommodate the increase in traffic, it is expected that the additional traffic will not cause a safety concern for vehicles or pedestrians. Difference in South Aspen Street Traffic with Proposed Development Prior to the recent reconstruction of South Aspen Street, skiers could access Lift 1A by parking on South Aspen Street or by driving up the hill to drop off skiers. The reconstruction of South Aspen Street eliminated much of the on-street parking. The site changes to relocate access to the ski lift combined with the proposed Lift One Lodge development moving skier drop-off to Dean Street significantly reduce the level of traffic on South Aspen Street south of Dean Street. In this section, a peak hour volume estimate based on Lift 1A skier loadings is developed for South Aspen Street prior to the reconstruction. This estimate will be compared to projected South Aspen Street peak hour traffic after the opening of the Lift One Lodge and Gorsuch Haus developments. The Gorsuch Haus Transit Strategy Memorandum (LSC June 27, 2016) provides Lift One day skier visits from the 2015-2016 ski season. This data shows that on an average day 153 skiers accessed the Mountain using Lift One and on a peak day 530 skiers accessed the Mountain using Lift One. Building on the assumption that most of the South Aspen Street traffic will be directly related to skier visits, Table 4 describes assumptions and calculations to convert these skier visits into peak hour vehicle-trips. As shown, it is estimated that peak hour traffic on South Aspen Street prior to its reconstruction was about 45 vehicle-trips on an average day and about 160vehicle trips on a peak skier day. Table 4. South Aspen Street Peak Hour Traffic Volume Estimate (Prior to Reconstruction) Description Parameter Average Day Peak Day Skiers Accessing the Mountain at Lift 1A Total First Scans Per the 2016 LSC Study 153 530 Number of skiers using the 50 on-street parking spaces1 2.75 skiers per car for garage 69 138 Number of skiers staying in nearby lodges that walk2 2.75 skiers per room 55 110 Number of skiers arriving by vehicle 29 283 Number of skiers arriving by transit See note below3 2 57 Number of skiers per car using the drop off area 1.75 skiers per car for garage Number of vehicles dropping off skiers 15 129 Number of skiers arriving at the peak hour 40% per previous work FHU has done for ski areas Peak hour number of vehicles using the drop off area 6 52 Peak hour number of vehicles leaving the drop off area 6 52 Peak hour number of vehicles using the 50 on-street parking spaces1 25 50 Shadow Mountain Lodge Trip Generation 7 7 Total Peak Hour Trips on South Aspen Street 44 160 December 3, 2018 Gorsuch Haus Development Page 4 1 it is assumed that on an average day half of the on-street parking spaces would fill during the peak hour. On a peak day all on-street parking spaces would fill during the peak hour 2Assumed 40 nearby lodges for skiers to stay in. 50% would be occupied on an average day and 100% would be occupied on a peak day 3RFTA data shows an 8% mode share for personal trips. Used this 8% for an average day but used 20% for a peak day With the development of Lift One Lodge and Gorsuch Haus it is anticipated that overall peak hour traffic on South Aspen Street will decrease significantly as both the drop-off/pick-up and parking operations related to the Lift One base will move from South Aspen Street to Dean Street. As shown in Table 5, peak hour traffic on South Aspen Street will increase on an average day but will decrease on a peak skier day. . Table 5. South Aspen Street Peak Hour Traffic Comparison Aspen Street Peak Hour Volumes South of Dean Street Prior to Recent Reconstruction After Development of Gorsuch Haus and Lift One Lodge1 Change in Peak Hour Trips Average Skier Day 44 73 29 vehicle increase Peak Skier Day 160 73 87 vehicle decrease 1Volume based on the following: • Gorsuch Haus trip generation estimate of 50 vehicles for the PM peak hour presented in Table 1. • Trip generation for the Shadow Mountain Lodge which equates to 7 peak hour vehicle-trips • Lift One Lodge Valet Service – The trip generation for lodging units is 32 vehicles per peak hour. Assumed 50% are related to the valet service. This equates to 16 trips. In addition to the change in passenger car activity on South Aspen Street, there will also be a change in operations that occur today at Lift 1A with the new Lift One portal which will result in a drop in commercial vehicle activity along South Aspen Street. For example, snow cat deliveries and trash removal for on-mountain restaurants will no longer occur at the Lift 1A site.