KIMLEY-HORN & ASSOCIATES 4 -2009

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SANTA ANA TRANSPORTATION SYSTEM IMPROVEMENT AREA (TSIA) STUDY SCOPE OF SERVICES Task A: Forecast Traffic The purpose of this task is to quantify future development, and develop the traffic forecasts that will be used for the nexus analysis, and document information about future roadway improvements (committed improvements as well as other potential improvements in the study area). The City of Santa Ana will provide a list of proposed future development within the study area and available traffic studies. If these developments represent less than full build -out of the City's General Plan, it is assumed that the City will also provide information about other potential future development (land use types, quantities, and locations) for the 2035 scenario. Estimates of development timing will be obtained from the reports or from City staff. To be able to use the land use information as the basis for OCTAM trip forecasting (rather than relying on OCTAM's socioeconomic forecasts), we will apply OCTA's Subarea Modeling Guidelines to convert the land use data to socioeconomic data and then generate trips (productions and attractions) by purpose. Analysis of existing traffic conditions will be needed as a base for developing the future traffic forecasts, and to demonstrate that the improvements in the fee program are not addressing existing congestion problems. Since traffic volumes are somewhat lower than normal during the current recessionary period, any new traffic counts will be reviewed and adjusted if necessary to be consistent with pre -recession counts. We are proposing several adaptations of OCTAM so the modeling will address the particular needs of this study: • We will incorporate the land use -based trip generation into OCTAM, while maintaining OCTAM trip levels outside the local area to provide reasonable growth in background (through) traffic for Build -out year analysis. • We will adjust trip generation to account for reduced trip -making associated with mixed use and transit - oriented developments. • We will post -process (adjust) the raw model outputs so the future forecasts will be based on, and consistent with, the existing traffic counts. As part of the modeling in this task, we will produce future traffic forecasts and Level of Service results for the study area roads and intersections, to lay the groundwork for identification of needed improvements in Task B. The updated list of committed improvements will be used in Task B to help identify potential improvements to alleviate existing congestion. The updated cost allocation table will provide information on sources and amounts of committed funding, so that those amounts will be excluded from the fee calculations in Task C. To maximize efficiency of the study process (so we won't need to go back later and redo work elements in response to feedback from the City), and avoid the need for more meetings than have been outlined in the RFP, we are proposing an interim data review process to obtain City feedback when each step is complete, rather than waiting until the end of the entire task. We will submit completed data elements (land use tables, committed improvements lists, existing traffic counts and LOS, future volumes and LOS, and cost allocation table) to the City when each is completed, and request review and comment before we apply those data in subsequent steps. Not only will this make the process more smooth and efficient, but it also will contribute to our step-by-step consensus -building process. The following section lists the activities that we have identified as part of each task component