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Attachment 60 - Memor from Fehr & Peers to Summerhill HomesFEHRt PEERS Improving Communities Since 1985 MEMORANDUM Date: March 3,2015 To: Wendi Baker, Summerhill Homes From: Katy Cole and Sarah Peters Subject: North 40 TIA Freeway impact Elimination from MXD trip generation SJ09 -1130 This memorandum addresses the following question: Considering MXD+ trip generation methodology, how many square feet of office use needs to be reduced to eliminate the freeway impact on Southbound 85 between Bascom and Union for Project Alternative A? SUMMARY OF RESULTS Based on the MXD+ model described in our memorandum dated December 3, 2014 (attached), we identified two land use scenarios for Project Alternative A that appear to eliminate the freeway impacts that were identified in the North 40 Specific Plan Transportation Impact Analysis (TIA) and North 40 Specific Plan Environmental Impact Review. • Option 1: Remove medical office and reduce general office to 40 ksf; all other land uses unchanged • Option 2: Remove general office and reduce medical office to 35 ksf; all other land uses unchanged As discussed in the memorandum from December, using MXD+ to estimate trips for Project Alternative B results in a reduction that would likely eliminate the freeway segment impact identified for that alternative; therefore, Alternative B is not discussed below. 160 W. Santa Clara Street I Suite 6751 San lose, CA 95113 1 (408) 278 -1700 1 Fax (408) 278 -1717 www,fehrandpeers.com ATTACHMENT 60 h Baker March 3, 2015 Page 2 of 4 2 ANALYSIS Step 1. Determine the Trip Reduction to Eliminate the Impact The North 40 Specific Plan Transportation Impact Analysis (TIA) identified significant impacts on two mixed -flow segments of State Route (SR) 85 under Project Alternative A. To eliminate these impacts, the project would have to add no more than 1 percent of capacity to these segments (46 or fewer trips on mixed -flow segments, or 54 trips total when HOV lanes are included). The segments are: • Southbound SR 85 from Winchester Boulevard to SR 17: As reported in the TIA, during the PM peak hour Project Alternative A adds 52 trips to the segment. To eliminate the impact, trips on this segment would have to be reduced by 12% (6 trips). • Southbound SR 85 from Bascom Avenue to Union Avenue: As reported in the TIA, during the PM peak hour Project Alternative A adds 71 trips to the segment. To eliminate the impact, trips on this segment would have to be reduced by 35% (25 trips). See Table 1 for a summary of this calculation. TABLE 1: NORTH 40 PROJECT ALTERNATIVE A FREEWAY IMPACT REDUCTION TARGET Trips Identified in TIA Target* (Max trips that can be added without a significant impact) % reduction in trips PM Peak Hour Trips on SR 85 (Mixed -flow) Winchester to SR 17 (SB) Bascom to Union (SB) 52 71 46 46 12% (6 trips) 35% (25 trips) * Note: Impacts on these segments resulted in the addition of over 1% of capacity. Capacity of these segments is 4600 vehicles /hour /lane, so the project would have to add no more than 46 trips during the PM peak hour to avoid an impact. Source: Fehr & Peers 2015. h Baker March 3, 2015 Page 3 of 4 • Step 2. Identify Land Use Options to Eliminate Impacts In December 2014, Fehr & Peers prepared a memorandum to provide information requested by the Town Council related to mixed use trip generation methodologies. The memorandum (dated December 3, 2014) describes the Fehr & Peers MXD+ model, which is a tool that combines the research /data from two mixed use methodologies: National Cooperative Highway Research Program (NCHRP) Report 684 and EPA MXD, which are among the best - researched mixed -use methodologies currently in use. The MXD+ model provides trip generation estimates for the North 40 Specific Plan Project Alternative A that are 23 percent lower than Institute of Transportation Engineer (ITE) rates, which were used to estimate project impacts in the TIA (see Table 2). Since a 12% trip reduction would eliminate the impact on the Winchester -SR 17 segment, using the MXD+ model to estimate trips would likely eliminate the impact identified on the Winchester -SR 17 segment. Using the MXD+ model to estimate trips yields a smaller, but still significant, impact on the Bascom -Union segment. To identify which land use options would eliminate the impact, we first identified a target: Reduce overall trip generation by 35 percent from the trip generation estimate in the TIA. The target was identified in terms of overall trip generation, rather than office trip generation, because the MXD+ model estimates trips to and from all land uses and accounts for the interaction between land uses, rather than to and from each land use on its own. As described below under Caveats, this method is likely to overestimate the extent to which land uses must be reduced in order to eliminate this impact. We used an iterative process to identify the reductions in medical and general office space that would be needed to eliminate the freeway impact. The size of the medical and general office land uses in the MXD+ model were reduced in 5,000 square foot increments until overall trip generation in the PM peak hour was reduced by 35 %. We identified two reduced office land use options through this process: • Land Use Option 1: Remove medical office and reduce general office to 40 ksf; all other land uses unchanged • Land Use Option 2: Remove general office and reduce medical office to 35 ksf; all other land uses unchanged Wendi Baker March 3, 2015 Page 4 of 4 1 1 Trip generation for these land uses are summarized in Table 2. Y, TABLE 2: NORTH 40 PROJECT ALTERNATIVE A TRIP GENERATION ALTERNATIVES Trip Generation Alternative (PM Peak Hour) Total Office Total % from TIA Space (ksf) ITE rates (TIA) 1,526 - 125 ksf MXD+ (December 2014) 1,170 23% 125 ksf MXD+ with Land Use Option 1 (Remove medical office and reduce 999 35% 40 ksf general office to 40 ksf) MXD+ with Land Use Option 2 (Remove general office and reduce 994 35% 35 ksf medical office to 35 ksf) Source: Fehr & Peers 2015, CAVEATS The approach identified here, which reduces overall trip generation, is likely to overestimate the amount of office space reduction needed to eliminate the freeway impact. This is because trips to and from office uses are typically longer than trips to and from retail uses, and therefore more likely to travel via freeways. As a result, office uses contribute more to freeway impacts than retail uses, and by targeting office uses, a smaller overall reduction in trips would yield a greater effect on freeway impacts. FEHR,, � PEERS MEMORANDUM Date: December 3, 2014 To: Trang TuNguyen, Town of Los Gatos From: Katy Cole and Sarah Peters, Fehr & Peers Subject: North 40 Specific Plan: Trip Generation Rate Comparison SJ09 -1130 INTRODUCTION The purpose of this memorandum is to review alternatives to ITE trip generation rates, such as rates developed for the EPA MXD and National Cooperative Highway Research Program (NCHRP) Report 684. These methodologies address trip generation for mixed -use developments. Mixed - use development trip generation methodologies are appropriate for the North 40 Specific Plan Area, where a variety of land uses, including housing, retail, hotel and offices, is proposed. Trip generation refers to the number of inbound and outbound vehicle trips generated by a project over a given period of time. Trip generation is estimated for proposed development projects in order to understand how much traffic will be added to the surrounding transportation network. This memorandum describes the difference between typical trip generation methodologies for single use sites and for mixed use sites, and evaluates the effect on trip generation forecasts for the North 40 project if trip generation were estimated using rates developed for mixed -use development projects. We also note whether, in our professional opinion, significant impacts would be reduced if trip generation were estimated using a mixed - use methodology. SUMMARY OF FINDINGS We prepared trip generation estimates for the two North 40 Specific Plan project alternatives using MXD +, a tool that combines two mixed -use trip generation methodologies (NCHRP 684 and EPA MXD) and provides greater overall accuracy than either method alone. These estimates were then compared to trip generation estimates used in the North 40 Specific Plan TIA, which were developed using rates published by the Institute of Transportation Engineers (ITE), with modest reductions to account for pass -by trips to retail uses on the site and to account for the site's mixed -use character. Trip generation for North 40 prepared using the MXD+ methodology was slightly lower than ITE rates during the AM peak hour and substantially lower in the PM peak hour. Reductions for each project alternative are as follows: 160 W Santa Clara Street I Suite 6751 San lose, CA 95113 1 (408) 278 -1700 1 Fax (408) 278 -1717 www.fehrandpeers.com Trang December ber 3 3, , 201 2014 JJ1\•+' Page 2 of 7 • Project Alternative A: AM peak hour reduction of 7% (49 trips) and PM peak hour reduction of 23% (356 trips) • Project Alternative B: AM peak hour reduction of 3% (49 trips) and PM peak hour reduction of 24% (352 trips) Based on this analysis, in our professional opinion using a mixed -use methodology to estimate trip generation could reduce the level of significant impacts identified in the North 40 Specific Plan TIA. TRIP GENERATION METHODOLOGIES Trip generation refers to the number of inbound and outbound vehicle trips generated by a project over a given period of time. Trip Generation for a project can be developed using a variety of mythologies. The Institute of Transportation Engineers (ITE) publishes national trip generation rates and methodology in the Trip Generation Manual and Trip Generation Handbook. ITE trip generation data and analysis methods primarily apply to single -use, free - standing sites, limiting their applicability to compact, mixed -use developments. In Santa Clara County, trip generation estimates for new development are typically based on rates published by ITE and then reductions are taken to account for mixed -use per the VTA Transportation Impact Study Guidelines. Trip generation for the North 40 Specific Plan TIA was estimated using ITE rates, with reductions taken to account for the project's mix of housing and retail and to account for retail customers who would stop at the project on their way to another destination. Mixed -use sites typically have several features that reduce auto trips compared to single -use development, including: • Complementary land uses, which allow residents and workers to access goods and services within the development. • Diverse land uses, which enable visitors to run several errands with a single auto trip. • Walkable urban design and well- connected streets, which make walking and bicycling more comfortable and convenient. Several methodologies have been developed to account for the unique trip generation characteristics of mixed -use sites. The two methodologies identified by the Los Gatos Town Council, NCHRP 684 and EPA MXD, are among the best - researched mixed -use methodologies currently in use. In its revised TIA Guidelines (October 2014), the Santa Clara Valley Transportation Authority (VTA) identified both of these trip generation methodologies as appropriate for mixed - use development in Santa Clara County. The National Cooperative Highway Research Program ( NCHRP) Report 684, Enhancing Internal Trip Capture Estimation for Mixed -Use Developments, analyzed three mixed -use developments in Georgia and Texas to understand travel interactions between six types of land uses: office, retail, restaurant, residential, cinema, and hotel. To test the accuracy of this analysis, researchers Trang J Decembber er 3 3,, 2014 Page 3 of 7 compared their results to trip generation studies conducted at seven mixed -use sites in Florida. The resulting methodology yields reductions for ITE trip generation rates based on the interactions between land uses. The EPA MXD Model was developed from a sample of 239 mixed -use developments in six metropolitan areas from across the United States. The methodology reflects how different aspects of a site, including the density and type of development, affect vehicle trip generation by providing nearby destinations and shifting trips to walking or transit. The resulting trip reduction approach has been tested at 27 sites, primarily in California. MXD+ is a trip generation methodology developed by Fehr & Peers as part of their internal research and development efforts in collaboration with the EPA to combine the strengths of the EPA MXD and NCHRP methodologies and data. The methodology was developed by combining the results from both methods and comparing the results against trip generation recorded at 27 mixed -use sites. The resulting trip generation estimates were found to be more accurate than either the EPA MXD or NCHRP 684 methodologies alone. In May 2013, the American Planning Association published a memorandum outlining the MXD+ methodology through its Planning Advisory Service. MXD+ has been used in several transportation impact analysis studies in Santa Clara County, including the Apple Campus 11 EIR, the Lawrence Station Area Plan for the City of Sunnyvale, as well as a number of transportation impact analysis projects in other Bay Area counties. Table A summarizes the research basis of these three methodologies. TABLE A - MIXED -USE TRIP GENERATION METHODOLOGIES Average Error Rate' Methodology Data Source Validation Professional Practice AM PM Daily 27 sites ASCE peer review Household surveys SANDAG EPA MXD (CA, UT, TX, GA, F4 (C 12% 8% 2% at 239 sites Environmental studies NC) (CA,WA) Traffic counts, sites NCHRP 684 interviews at 3 (FL) NCHRP review panel 30% 18% N/A sites (GA and TX) Combined sources Combined sources (27 sites used for APA Planners Advisory MXD+ from EPA MXD 12% 4% 2% EPA MXD and Service Memo and NCHRP 684 NCHRP 684) Note: 1. Average error rate when compared to vehicle trip counts at 27 validation sites. Source: Walters, 1., B. Bochner, R. Ewing. Getting Trip Generation Right: Eliminating the Bias Against Mixed Use Development Planners Advisory Service, American Planning Association. May 2013. Trang j Decembber er 3 3,, 2014 Page 4of7 TRIP GENERATION ANALYSIS To understand how the application of a mixed - use - oriented trip generation methodology could affect trip generation for the project, we developed trip generation estimates using the MXD+ tool and compared them to the trip estimates used in the North 40 Specific Plan TIA, which were developed using ITE rates. TIA Trip Generation Trip generation for the North 40 Specific Plan TIA was estimated by using rates published by the Institute of Transportation Engineers (ITE) in its Trip Generation report and Trip Generation Handbook. Separate trip reductions were taken to account for pass -by trips to retail uses on the site and to account for the site's mixed -use character. These reductions were based on guidance published by the Santa Clara Valley Transportation Authority (VTA), as follows: • Pass -by reductions: VTA publishes guidance for diverted and pass -by trip reductions in its Transportation Impact Analysis Guidelines (2009). Pass -by and diverted link trips are intermediate stops made as a driver is going to their final destination. For example, a driver may stop at a bank on their way home from work. This trip is not new to the roadway network: therefore, it should not be included in the transportation impact analysis. ITE studies report that pass -by and diverted linked trip reduction rates average 34 percent for retail uses (Trip Generation, 2004). VTA guidelines list slightly lower trip reduction rates. To present a conservative analysis and comply with VTA guidelines, we reduced retail trips by 25 percent. Project driveway analysis was adjusted to reflect changes • Mixed -use reductions: The VTA Transportation Impact Analysis Guidelines (2009) provide guidance for reducing ITE trip generation estimates at mixed -use developments. To account for the mix of land uses proposed in the North 40 Specific Plan, a trip reduction was applied to reflect a 15 percent reduction of residential trips plus an equal number of matching trips generated by retail uses. This resulted in a total mixed -use reduction of 784 daily trips, 60 AM peak trips and 76 PM peak trips, or 30 percent of all residential trips for both project alternatives. Table B presents trip generation developed for the two project alternatives in the North 40 Specific Plan TIA. Project Alternative A • Retail: 269,000 square feet • Hotel: 150 rooms • Office: 125,000 square feet (62,500 square feet of medical /dental office and 62,500 square feet of general office space) • Residential: 364 units (73 cottage cluster units, 73 apartments and 218 condominium /townhouse units) Trang December ber 3, 3, 201 2014 Page 5 of 7 Project Alternative B • Retail: 400,000 square feet • Hotel: 150 rooms • Residential: 364 units (73 cottage cluster units, 73 apartments and 218 condominium /townhouse units) MXD+ Trip Generation To understand whether using a mixed -use trip generation methodology could change trip generation estimates, we prepared trip generation estimates the two project alternatives in the North 40 Specific Plan TIA using the MXD+ methodology. As outlined above, the MXD+ methodology combines the NCHRP 684 and US EPA methodologies and provides greater overall accuracy than either method alone. To be consistent with the analysis presented in the TIA, a pass -by reduction of 25% was applied to retail trip generation. Table B presents trip generation for two project alternatives developed using the MXD+ tool. TABLE B - COMPARISON OF ALTERNATIVE TRIP GENERATION ESTIMATES FOR THE NORTH 40 SPECIFIC PLAN AREA Daily AM Peak PM Peak Method In Out Total In Out Total In Out Total Project Alternative A TIA' 7,880 7,877 15,757 422 263 685 690 836 1,526 MXD +2 7,080 7,077 14,157 392 244 636 529 641 1,170 Difference -800 -800 -1,600 -30 -19 -49 -161 -195 -356 % Change -10.2% -7.2% -23.3% Project Alternative 8 TIA' 7,750 7,750 15,500 229 240 470 761 727 1,488 MXD +2 6,879 6,879 13,758 221 231 453 581 555 1,136 Difference -871 -871 -1,742 -8 -9 -17 -180 -172 -352 % Change -11.2% -3.6% - 23.7.01 Note: 1. Per VTA TIA Guidelines (2009), trip generation for retail uses was reduced by 25% to account for pass -by trips. Trip generation for residential uses was reduced by 15% to account for "trip capture' by project retail. An equal amount of retail trips were removed. 2. Trip generation for retail uses was reduced by 25% to account for pass -by trips. Sources: North 40 Specific Plan TIA, March 2014; MXD+ 2.0 trip generation analysis tool, October 2014. Trang Decembber er 3 3,, 2014 Page 6 of 7 Results As shown in Table B, trip generation for North 40 prepared using the MXD+ methodology was slightly lower than the 11A trip generation during the AM peak hour and substantially lower in the PM peak hour. Reductions for each project alternative are as follows: • Project Alternative A: AM peak hour reduction of 7% (49 trips) and PM peak hour reduction of 23% (356 trips) • Project Alternative B: AM peak hour reduction of 3% (49 trips) and PM peak hour reduction of 24% (352 trips) Based on this analysis, in our professional opinion using a mixed -use methodology to estimate trip generation could reduce the level of significant impacts identified in the North 40 Specific Plan TIA. The TIA identified significant and unavoidable freeway impacts for both project alternatives. These impacts could be eliminated if 46 or fewer project trips were assigned to mixed -flow lanes and 8 or fewer project trips assigned to HOV lanes. In the TIA, freeway impacts were identified as follows: Project Alternative A: • Southbound SR 85 from Winchester Boulevard to SR 17: The PM peak hour impact results from 52 project trips being added to mixed -flow freeway lanes. If a project has 46 trips or fewer in the mixed -flow lanes the impact is considered less -than- significant. Therefore, if North 40 added 6 fewer trips to the freeway (or 12% fewer), the impact may be eliminated. Based on our professional, since using a mixed -use methodology could result in an overall PM peak hour trip reduction of 23.3% this significant freeway impact may be eliminated. • Southbound SR 85 from Bascom Avenue to Union Avenue: The PM peak hour impact results from 71 project trips being added to mixed -flow freeway lanes. If a project has 46 trips or fewer in the mixed -flow lanes the impact is considered less -than- significant. Therefore, if North 40 added 25 fewer trips to the freeway (or 35% fewer), the impact may be eliminated. Based on our professional, since using a mixed -use methodology may result in an overall PM peak hour trip reduction of 23.3% this significant freeway impact would likely remain. Trang / December ber 3, 3, 201 2014 Page 7 of 7 Project Alternative B: • Southbound SR 85 from Bascom Avenue to Union Avenue: The PM peak hour impact results from 48 project trips being added to mixed -flow freeway lanes. If a project has 46 trips or fewer in the mixed -flow lanes the impact is considered less -than- significant. Therefore, if North 40 added 2 fewer trips to the freeway (or 4% fewer), the impact may be eliminated. Based on our professional, since using a mixed -use methodology could result in an overall PM peak hour trip reduction of 23.7% this significant freeway impact may be eliminated. This Page Intentionally Left Blank