Published on March 11, 2008
New Pleasanton Home Depot/Regency CenterProposed Project: New Pleasanton Home Depot/Regency Center Proposed Project Could the City’s traffic assumptions be understating the real traffic impact? Prepared by Nancy Allen Summary: Summary The # 1 concern of Pleasanton residents is traffic congestion. The most impacted are roadways near the Stanley/Bernal/Valley corridor (especially Santa Rita/Valley) effecting tens of thousands of drivers a day. Adding a large-scale retail development in this area will make traffic worse. Current traffic reports show that even with all of the mitigations identified, critical intersections are on the cusp of being unacceptable if this development is approved. For example, Santa Rita/Valley will be at 53.5 LOS with all mitigations (even with a 3rd sblt). It only takes about one more car/minute during peak hours to drop the service to an unacceptable level. If any assumptions used in the City’s traffic report are slightly off, congestion could be much greater than forecasted and cause unacceptable LOS even with mitigations. Because traffic is so close to the cusp, it is essential to validate key assumptions in the current traffic report to insure they are as conservative as possible. To substantiate documentation for discount factors, the City agreed on 11/15 to run a worst case analysis because the latest traffic report may have errors which could understate the real traffic congestion impact. If traffic impacts are higher than forecasted, building SDE may be the best mitigation. Or, could there be another alternative??? Calculating traffic impact is similar to calculating income tax.The more you deduct from your gross income,the lower your net taxable income.: Calculating traffic impact is similar to calculating income tax. The more you deduct from your gross income, the lower your net taxable income. A Traffic Analysis is very similar: A Traffic Analysis is very similar *Home Depot Analysis, Dowling and Associates, 7/2006, page 13. Confirmed 242 by M. Tassano on 11/1/07. Traffic deductions used in the Regency analysis aremuch greater than other Benchmarked Cities and the CA DOT.: Traffic deductions used in the Regency analysis are much greater than other Benchmarked Cities and the CA DOT. Sources: See next pages and appendix for further detail on other cities and California Dept. of transportation; We gathered publicly-available information to verify if the methodology (assumptions) used by other cities was directionally consistent with the information in the City of Pleasanton’s report. Nothing is exactly 100% apples for apples, which is why we collected at least 6 points (plus more in the appendix). We validated it with the CA Dept. Of Transportation (DOT) standards. The approach others used to determine two key deduction assumptions differed significantly with the approach Pleasanton took. The net impact is that others forecasted a net traffic impact much greater than the Pleasanton forecast (i.e.: 541 to 773 trips vs. Pleasanton’s projection of 242). Assumes same land use and square footage as the starting point. Why such differences between Assumptions used? : Why such differences between Assumptions used? Internal capture – Other cities did not apply this category saying there is no reliable industry standard to use. Even the ITE cautions that its information relied directly on data collected at only 6 multi-use sites in Florida. The sites are all large “mini-villages” with combinations of at least 2 land uses across hotel or residence/commercial/retail. They did not research standalone “retail-only” sites, such as the proposed Regency site. The ITE further cautions to only use its data for comparable situations and to validate with local data, wherever possible, as their data set is narrow and limited. Passby – Other cities use much more conservative assumptions, and they do not rely primarily on ITE data. Others said ITE passby data on its own should not be relied on, especially when sample sizes are small. (The ITE sample used by Pleasanton is only 3 studies in Florida 15 years ago.) Others set a maximum passby of about 0-30% (if there is back-up documentation) or did a site specific study to be conservative. In a site specific study, Milpitas found a 15% passby rate at 3 Home Depot sites off busy 6 lane arterial roads. Most conservative bias – In the absence of credible data, others recommended to be conservative to protect city and residents of bearing the burden of mistakes in traffic projection. The ITE Handbook cautions to apply their data Appropriately and Conservatively: The ITE Handbook cautions to apply their data Appropriately and Conservatively The ITE data on internal capture does not apply to Pleasanton’ situation and should not be used at all. The ITE handbook says their data is based on a small sample (6) of studies in Florida and only at large true multi-use developments. (The study only addressed a combination of retail/commercial/ residential uses.) Data did not include “retail-only centers (see appendix). The ITE data the City of Pleasanton used for the Home Depot passby assumption was based on just 3 data points (in Florida and 15 years old). The ITE Handbook cites (and boldfaces): "If the Handbook has an insufficient number of data points, the analyst should collect local data and establish a local rate" and “if the number of data points is three, four or five, the analyst is encouraged to establish a local rate." The ITE further states, “Due to the limited amount of passby data availability and the inherent variability in surveyed site characteristics, it still has proven difficult to obtain high correlation rates.” In the absence of any (credible) data, the ITE says, “It is better to overestimate off site vehicle trips”. Appendix: Appendix Requests for City staff Internal capture references Passby references Back-up: current and future LOS at Santa Rita/Valley Requested Questions/Validation for City Staff: Requested Questions/Validation for City Staff Create a worst case scenario without deductions to determine impact on poor performing intersections. (City staff agreed to do this.) Independently validate all deduction rates originally used (vs. other benchmark data and ITE sample data) to insure we have the most credible and conservative estimate from the City. We ask that sample sizes and ITE cautions be clearly communicated if the City chooses to use any ITE data on passby and internal capture. Please provide detailed documentation, and any comparable studies, to support key assumptions. Mike T. said he would gather other Pleasanton traffic studies to have rough ballparks, including the Johnson location. I recommended he also obtain the Milpitas traffic study on Home Depot which is near 6 lane arterial roads. It may provide more relevant information on passby than the 15 year-old Florida study. Be Conservative to Protect the Public: Be Conservative to Protect the Public “Major concern has been raised when the traffic study identifies a trip generation rate that is less than what ultimately is experienced once the development is built and occupied. Because entitlement has been granted, the impacts of the traffic from underestimating the trip generation is experienced by the community. Subsequent modifications or improvements, if possible, become the burden of the public. It is recognized that the trip generation process is ultimately dependent on a number of market and social factors; however, it is imperative that the traffic impact study be sufficiently conservative to account for full impact of the proposed development” Source: http://www.townofchapelhill.org/index.asp?NID=424 Internal Capture Assumptions: Internal Capture Assumptions http://ladpw.org/Traffic/Traffic%20Impact%20Analysis%20Guidelines.pdf LA County Public Works, Traffic Impact Analysis Guidelines, 1/07 Internal trip reduction can only be applied for mixed-use types of developments. Internal or pass-by trip reduction assumptions will require analytical support based on verifiable actual similar developments to demonstrate how the figures were derived and will require approval by the County. http://www.dot.ca.gov/hq/tpp/offices/ocp/igr_ceqa_files/tisguide.pdf“ Captured Trips – Captured trip reductions greater than 5% requires consultation and acceptance by Caltrans. http://www.ncdot.org/doh/preconstruct/traffic/congestion/CM/docs/TIA.pdf Internal capture calculations should be used cautiously. Reductions for internal capture should be applied to multi-use, or mixed-use, sites only. A multi-use site must contain two or more land use types, i.e., retail, office, and/or residential. Refer to Chapter 7 of the HANDBOOK for further descriptions and explanations regarding internal capture trips. •percentage. Internal capture should not be taken from retail only sites, for AM peak hours, or from lodging land uses. http://pubserv.ci.columbus.oh.us/transportation/Adobe%20Files%20after%20Sep%2005/Traffic%20Standards%20Code.pdf Very little data has been collected locally or elsewhere to quantify the extent of internal trip-making within a mixed use development. Common current practice is to consider internal trip reductions only where mixed use developments consisting of at least two major complementary uses exist. This includes such complementary use combinations as office/retail, office/hotel, office/residential, retail/residential, and office/restaurant. Other combinations may be considered as well. Reductions for internal trip-making will be accepted only if based on actual surveys of similar developments or research as approved by the Division of Traffic Engineering and Parking. Definition of MUD A Multi-Use Development (MUD) may be described as a concentration of compatible land uses which are physically integrated by means of internal pedestrian or roadway network system. The multi-use development was initially a concept of private developers who were aware of its market potential. They were also influenced by public planning agencies which became aware of the need to encourage Planned Unit Development (PUD). A PUD is usually defined as a variety of land use types with a predominance of residential development. A PUD by definition is different from a multi-use development (MUD) which consists of more retail and office uses Because MUD/PUD land use components tend to complement each other, it reduces the need for persons to make vehicular trips beyond the development. The composition of a MUD/PUD determines the amount of iinteraction among its land use components. ITE Internal Capture for Multi Use Development Sources : ITE Internal Capture for Multi Use Development Sources Below is the ITE source data that Pleasanton used to develop internal capture deductions. The data is not comparable - comparing a 16 acre “retail only” parcel is not comparable with comparing large multi-use developments the ITE studied. That is why ITE provides all sources and cautions users to only apply if truly comparable, and strongly recommends local data. Example - Mizner Park A 29 acres mixed-use urban development consisting of 237,000 sf of retail 272 residential apartments, and 105, 000 sf of office space. As one of the nation's first true mixed-use new urbanism projects, Mizner Park in downtown Boca Raton is a "village within the city". The project is a unique public-private venture encompassing a city block with commercial, cultural and residential elements. Plaza Real, a city park, runs through the center of the project. Mizner Park became a catalyst for revitalization of the city's downtown and remains the heart of world-renowned Boca Raton. Commercial components consist of 45 shops, nine restaurants, a cinema, professional office space above retail, a free-standing office tower and 272 residences including apartments and townhomes. Passby Assumptions: Passby Assumptions Passby Assumptions (continued): Passby Assumptions (continued) http://www.dot.ca.gov/hq/tpp/offices/ocp/igr_ceqa_files/tisguide.pdf, pg 7 Caltrans says passby "Reductions greater than 15% requires consultation and acceptance by Caltrans." Justification for exceeding a 15% reduction should be discussed in the TIS. http://www.tlma.co.riverside.ca.us/trans/documents/pamphlets/traffic_impact_anaylsis.pdf 8/2005 Page 13 of 23. Defines Riverside standards for traffic impact studies. A maximum of 25% passby assumption allowed with documentation. http://www.ci.el-cajon.ca.us/content/city_council/07-27-99minutes.htm Traffic Study for El Cajon HD Rick Crafts, RCE Traffic Engineering, 9255 Dillon Drive, La Mesa, advises he worked closely with the City, CALTRANS, the County and SANDAG in preparing the traffic study. The data was not manipulated to make the project work. As far as the 100,000 ADT that the Arnele site is generating, that is true and further demonstrates the overwhelmed state of that store. Counts were used to determine the peaks and peak percentages. A rate of 60 trips per 1000 was used, which corresponds to regional and nation wide studies of existing Home Depot sites. They did not use Passby reductions on the numbers to reduce the figures and it is a conservative study. http://www.lic.wisc.edu/shapingdane/facilitation/all_resources/impacts/analysis_traffic.htm, The percentage of pass-by trips varies by land use. The Institute of Transportation Engineers recommends the adjustments for pass-by trips included in Table 3.4. For example, “standard trip generation rates indicate that a 300,000 square foot shopping center would generate approximately 1,320 PM peak hour trips at its driveways. Given the above pass-by percentage of 25 percent, the amount of additional traffic on the adjacent roadway sys-tem would be approximately 990 trips (1,320 X 1 - .25). Passby Assumptions (continued): Passby Assumptions (continued) http://www.ci.fremont.ca.us/NR/rdonlyres/e5acxhg4c3ojklz354gwvs7e2b2e4v52lslutu4mjl2kbjuzqf4ocp4udoqxoyzr35m5ri7ywr7xvb5rt6pio3wjjig/GlobeDEIRall051025.pdf EIR, 10/2005 for large retail shopping center in Fremont, Lampier Gregory and Hexagon (page 72) A 25 percent passby rate was applied to the shopping center and restaurant peak hour trips. These estimates are conservative based on ITE rates, which show pass-by rates of between 26 percent and 34 percent for retail uses. The word “primary” is used to describe new trips that would be added to the roadway network, while “pass-by” is used to differentiate trips that are assumed to already be on the roadway network. http://www.sandag.org/uploads/publicationid/publicationid_1140_5044.pdf Suggested PASS-BY [undiverted or diverted <1 mile] percentages for trip rate reductions only during P.M. peak period (based on combination of local data/review and Other sources**): COMMERCIAL/RETAIL Regional Shopping Center 20% Community " " 30% (15-40 acres, 125,000-400,000 sq. ft.,w/usually 1 major store, detached restaurant(s), grocery and drugstore) Neighborhood " " 40% Specialty Retail/Strip Commercial (other) 10% Supermarket 40% Convenience Market 50% Discount Club/Store 30% FINANCIAL Bank 25% AUTOMOBILE Gasoline Station 50% RESTAURANT Sit-down high turnover 20% Fast Food 40% Albany Oregon, Engineering standards, June 2006 14. ESTIMATION OF PASS-BY TRIPS Pass-by trips are those made as intermediate stops on the way from an origin to a primary trip destination. They do not affect the driveway or site access volumes but do affect the amount of traffic added to the adjacent street system. Pass-by trips can be estimated for certain types of commercial developments using the most current version of the ITEs’ Trip Generation Manual. However, since this methodology is still being developed, the City shall approve pass-by trip estimates for each development on a case-by-case basis, and reserves the option of not allowing pass-by trip reductions if sufficient supporting data is absent. Current/Future LOS at Santa Rita/Valley: Current/Future LOS at Santa Rita/Valley E level of service for peak p.m. if LOS deteriorates by 1.5 seconds (to 55.0) “Adding trips to the SBLT and the WBRT increased the LOS to E with the addition of 80 trips beyond the Existing + Approved + Stanley. This is not entirely fair, in that the EBTH movement is not a critical movement, and Home Depot does add trips to this movement without impacting delay. Given that the Home Depot Project does distribute vehicles in the through movements, and adding 20 trips to the EBTH did not impact the LOS, I would give an acceptable range of added trips to be 80 to 100 to deteriorate to LOS E.” This is just over 1 car per minute. (11/1/8 M. Tassano) Q and A: The original Home Depot Traffic Report was completed in July of 2006. The triple southbound left was identified as a necessary mitigation to bring the intersection to LOS D and was included in all traffic model runs. The supplemental report also includes Santa Rita @ Valley with a triple southbound left turn. The table below shows the levels of service with the various Home Depot scenarios.