. This session will explain the internal traffic capture of mixed-use projects and the benefits that can be achieved through shared parking. Georges Jacquemart, PE, AICP Principal, BFJ Planning www.bfjplanning.com (212) 353 7477
Why do we see more mixed-use projects? Desire to create more walkable communities Desire to move away from large single-use zones The trend of mixed-use projects is reflected in zoning changes such as form-based zoning and variations thereof Apartments and retail at 14 Hudson in Glens Falls, NY Mixed-use projects reduce the developers risks Re-use of older buildings Mixed commercial/residential at The Algonquin in Saratoga Springs 2
Princeton Forrestal Village 3
Advantages of Mixed-Use Projects Reduced traffic generation due to internal capture of traffic, some of the vehicular trips become walking trips For very large sites some of the internally captured trips could be vehicular trips, but the external traffic generation would be reduced Total parking demand of a mixed-use project is generally less than the cumulative parking demands of all uses. The different peaking characteristics allow us to reduce the parking supply through the shared-parking methodology. The above benefits can be realized if we have a mix of uses in a building or on a parcel and in some cases on separate adjoining parcels as long as persons can walk from one parcel to the other or they can drive via internal connections 4
Reduced Traffic Impacts of Mixed-Use Projects Calculating the traffic generation of a mixed-use project: 1: Traffic Generation without internal capture Size ITE Rates Vehicle Trips Building Use 1000 Sq. Ft. or Dwelling AM Peak Hour PM Peak Hour AM Peak Hour PM Peak Hour Units In Out In Out In Out In Out Supermarket 60 2.19 1.4 5.36 5.15 131 84 322 309 Apartments 1000 0.1 0.41 0.4 0.22 100 410 400 220 Office 180 1.36 0.19 0.25 1.24 245 34 45 223 Gross Total Traffic 476 528 767 752 5
Reduced Traffic Impacts of Mixed-Use Projects 2: Estimating Internal Capture Size ITE Rates Vehicle Trips Building Use 1000 Sq. AM Peak PM Peak AM Peak Hour PM Peak Hour Ft. or Dwelling Unit In Out In Out In Out In Out Supermarket 60 2.19 1.4 5.36 5.15 131 84 322 309 Apartments 1000 0.1 0.41 0.4 0.22 100 410 400 220 Office 180 1.36 0.19 0.25 1.24 245 34 45 223 Gross Total Traffic 476 528 767 752 Minus Internal Trips Internal Capture Supermarket to Apartments 15 13 13 46 46 Apartments to Supermarket 15 20 20 33 33 Office to Apartments 5 2 2 11 11 Apartments to Office 5 12 12 2 2 Supermarket to Office 15 13 13 7 7 Office to Supermarket 15 5 5 33 33 Total Internal Trips Net Total Trafic 15 OF MIN (84,100) 5 OF MIN (410,245) 64 64 133 133 412 464 634 619 Internal Capture 15.5 13.8 21.0 21.5 Average Internal Capture 15.6 Verification of Total Internal Trips AM Peak Hour PM Peak Hour Internal of Internal of Trips Total Trips Total out of supermarket 25 30 53 17 into supermarket 25 19 66 21 out of apartments 32 8 35 16 into apartments 14 14 58 14 out of office 7 20 45 20 into office 25 10 9 20 6
Reduced Traffic Impacts of Mixed-Use Projects Internal Capture of a Project with 1000 Apartments and 20,000 SF Office Size ITE Rates Vehicle Trips Building Use 1000 Sq. AM Peak PM Peak AM Peak Hour PM Peak Hour Ft. or Dwelling Unit In Out In Out In Out In Out Apartments 1000 0.1 0.41 0.4 0.22 100 410 400 220 Office 20 1.36 0.19 0.25 1.24 27 4 5 25 Gross Total Traffic 127 414 405 245 Minus Internal Trips Internal Capture Office to Apartments 5 0.2 0.2 1.2 1.2 Apartments to Office 5 1.4 1.4 0.3 0.3 Total Internal Trips Net Total Trafic 1.6 1.6 1.5 1.5 126 412 404 243 Internal Capture 1.2 0.4 0.4 0.6 Average Internal Capture 0.5 7
PM Peak-Hour Traffic Generation Single-Use, Suburban Condition 8
PM Peak-Hour Traffic Generation Mixed-Use Condition 9
Reduced Traffic Impacts of Mixed-Use Projects Conclusions Traffic reductions of mixed-use projects are real, but can vary significantly depending on mix and individual sizes of uses We should not use a fixed as a credit for mixed-use traffic generation This effect is similar to the shopping center effect or traffic impacts in denser downtown areas Market Center at Railroad Place, Saratoga Springs Other Related Methodologies ITE Methodology Described in the ITE Trip Generation Handbook 3 rd Edition (Sept 2017) NCHRP Report 684: Enhancing Internal Trip Capture Estimation for Mixed-Use Developments Mixed use development in Denver, CO 10
Reduced Traffic Impacts of Mixed-Use Projects What is Shared Parking? Shared parking takes advantage of the fact the parking demands of our various land uses do not overlap in time or do not peak at the same time It is a strategy that allows us to optimize the use of our parking resources and reduce the overall supply of parking needed The shared parking supply needs to be within comfortable walking distance to the uses being served Assigned parking spaces No shared spaces can be assigned or reserved 11
Calculating the Shared-Parking Benefits of a Mixed-Use Project Parking Calculation for Office/Movie Theater without Sharing Building Use Size Peak Parking (individual peaks) 1000 SF or seats Ratio Spaces Office 100 3 300 Cinema 1200 0.36 432 Total 732 Shared Parking Calculation for Office/Movie Theater Mix Building Use Size Peak Parking (indivdl peaks) Weekday AM (10-11 am) Weekday Lunch (12-2 pm) Weekday PM (3-4 pm) Weekday Evening (7-8pm) Saturd Midday (12-2 pm) 1000 SF or seats Ratio Spaces Present Present Present Present Present Office 100 3 300 100 300 85 255 90 270 10 30 20 60 Cinema 1200 0.36 432 0 0 45 194 55 238 100 432 65 281 Total 732 300 449 508 462 341 Peak Parking Demand: 508 Shared Parking Savings: 224 31 12
Calculating the Shared-Parking Benefits of a Mixed-Use Project Westchester Pavilion Shared Parking Calculation Peak Parking Weekday AM Weekday Lunch Weekday PM Weekday Weekday Night Saturday Midday Individl Peaks (10-11 am) (12-2 pm) (3-4 pm) Evening (7-8 pm) (12 am-6am) (12-2 PM) Uses Size Units ITE Code Ratio Spaces Present Present Present Present Present Present Apartments 700 Dus 222 1.20 840 45 378 40 336 40 336 66 554 100 840 60 504 Retail 52.5 1000 GLA 820 3.00 158 60 95 80 126 80 126 80 126 0 0 100 158 Fitness Club 38.0 1000 GA 492 4.00 152 51 78 45 68 45 68 100 152 0 0 90 137 Hi turn over restaur 5.5 1000 GA 932 6.25 34 65 22 80 28 40 14 100 34 0 0 100 34 Quality Restaurant 15.0 1000 GA 931 9.50 143 20 29 56 80 30 43 100 143 0 0 100 143 Total 111 1000 SF 1326 601 638 587 1009 840 975 Shared Parking Savings: 24 spaces saved 317 (+/- $15 Million) 13
Calculating the Shared-Parking Benefits of a Mixed-Use Project Shared Parking Calculation for 200k SF Office/10K SF Retail Mix Building Use Size Peak Parking (individ. peaks) Weekday AM (10-11 am) Weekday Lunch (12-2 pm) Weekday PM (3-4 pm) Weekday Evening (7-8pm) Saturd Midday (12-2 pm) 1000 SF Ratio Spaces Present Present Present Present Present Office 200 3 600 100 600 85 510 90 540 10 60 20 120 Retail 10 5 50 70 35 85 43 75 38 70 35 100 50 Total 650 635 553 578 95 170 Peak Parking Demand: 635 Shared Parking Savings: 15 2 14
Conclusions Benefits from shared parking can vary substantially depending on the number of uses and their magnitude Zoning codes should require a shared-parking analysis for each project, not offer a flat credit The shared-parking analysis needs to estimate the parking demand for each component use and for each critical time period Critical time periods typically include weekday mornings, weekday lunch time, weekday afternoons, weekday evenings, weekday nights, Saturday middays The parking ratio given by zoning should be used as the base peak ratio The presence ratios can be based on parking generation data by ITE or on specific occupancy surveys of similar uses, possibly only for the critical periods 15
Frequent Questions and Concerns What if I have an emergency and come home to my apartment during the day? What if some of the uses change? What happens on Black Friday when some people don t work? Should the shared spaces be signed for particular uses and particular time periods? Could we assign 1 space per apartment and use the balance of spaces as shared spaces? What are the shared parking benefits in a TOD project? Lower parking ratios for residential uses, higher percentage of cars staying in garage, do the residential cars leave early enough to make room for the transit commuters? 16
Shared Parking Scenario 17
The Issues with Assigned Parking Spaces in Multi-Family Residential Projects Shared parking will not work with assigned parking spaces If we don t have assigned spaces we can reduce the parking ratios required by zoning for large projects If we don t have assigned spaces we don t need to provide spaces for visitors in large projects. Parking can be shared between residents and visitors. Does the market require assigned parking spaces or is that a myth? 18
QUESTIONS?. Georges Jacquemart, PE, AICP Principal, BFJ Planning www.bfjplanning.com (212) 353 7477 January 31, 2018