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Wayne Rasmussen July 25, 2013 Page 3 of 11 Two significant new research studies provide the opportunity to improve the state of practice. One study sponsored by the US EPA and another by the Transportation Research Board2 have developed means to improve trip generation estimation for mixed-use development (MXD). The two studies examined over 260 mixed-use development sites throughout the U.S. and, using different approaches, developed new quantification methods. Fehr& Peers has reviewed the two methods, including the basis, capabilities, and appropriate uses of each, to produce a new method (MXD+) that combines the strengths of the two individual methods. MXD+ recognizes that traffic generation by mixed-use and other forms of sustainable development relate closely to the density, diversity, design, destination accessibility,transit proximity, and scale of development. MXD+ improves the accuracy of impact estimation and gives planners a tool to rationally balance land use mix and to incorporate urban design, context compatibility, and transit orientation to create lower-impact development. The MXD+ methodology starts with ITE trip generation estimates but then adjusts those estimates to account for the mixed-use and environment characteristics. Use of the MXD+ methodology requires more input data than a traditional trip generation application. Data detailing the geographic layout of the site, land use in the surrounding area, and socioeconomic data of both the site and the surrounding area were collected to inform the MXD+ methodology. Model inputs, in addition to land use information, include the number of jobs within a 30 minute transit ride of the EPSP area, the expected level of auto-ownership, and average household size. Sources used to collect this data include the Contra Costa Transportation Authority(CCTA)travel demand model, the Metropolitan Transportation Commission (MTC)travel demand model, Census and American Community Survey (ACS), the Bay Area Travel Survey (BATS), and the Specific Plan Options. Table 2 shows the trip generation potential of each option through several different transportation metrics. External vehicle trips represent trips that would interact with roadway facilities outside the Project area and could potentially result in off-site traffic impacts. Internal capture represents trips that have both an origin and destination within EPSP, including residents ' Traffic Generated by Mixed-Use Developments—A Six-Region Study Using Consistent Built Environmental Measures(Ewing et al,ASCE UP0146, Sept 2011) 2 National Cooperative Highway Research Program (NCHRP) Report 684 Enhancing Internal Trip Capture Estimation for Mixed-Use Developments(Bochner et al, March 2011)