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<br />Saltworks Proposal- Transportation Group Summary Report (22 January 2010) <br /> <br />7A - ATTACHMENT NO.4 <br />Page 15 <br /> <br />CHAPTER 3 - TRAVEL DEMAND ESTIMATES <br /> <br />An important part of the transportation team's review is to determine whether the proposed internal transportation <br />system and the proposed connections to the external transportation system are adequate in terms of <br />accommodating all travel modes and having sufficient capacity to carry anticipated demands for each mode. <br />Since no formal transportation analysis has been prepared for the project, a planning level analysis focusing on <br />the vehicle demand and the roadway capacity of the external connections, and the demand for the proposed <br />transit system compared to the proposed transit system's design was conducted for this assessment. <br /> <br />Due to the scale of the project, estimates of the vehicular and transit demand of the Saltworks proposal need to <br />consider the land use types and sizes, and their relative locations to each other and to other local and regional <br />destinations. The travel demand forecasting models currently available to develop estimates and potential <br />limitations of these models are described in Section 3.1 below. Preliminary estimates provided by Hexagon are <br />discussed subsequently in Section 3.2. Planning level estimates of peak hour trips prepared by Fehr & Peers for <br />our evaluation of the internal roadway system and connections to the external roadway system, appear in this <br />chapter in Section 3.3. An assessment of the roadway system based on these estimates is discussed in the <br />subsequent chapters. The preliminary transit ridership projections were used by Shiels Obletz Johnsen in their <br />assessment of the circulator transit system discussed in Chapter 5. <br /> <br />3.1 AVAILABLE TRAVEL DEMAND FORECAST MODELS <br /> <br />There are two existing travel demand forecast models that include the City of Redwood City and the Saltworks <br />project area. These models are the San Mateo City/County Association of Governments (C/CAG) and the City of <br />Redwood City's travel demand forecast models. The C/CAG model is a county-level regional model, which is <br />based on the Metropolitan Transportation Commission's nine-county regional model. The current C/CAG model <br />was created in 1990 and was last updated in 2005. The C/CAG model is currently used for planning regional <br />roadway improvements and is principally designed to assess regional transportation projects and regional travel <br />behavior. The C/CAG model includes a mode choice model for estimating transit ridership; however, it is <br />important to note that the transit component of the model has not been calibrated or validated for current <br />conditions. <br /> <br />The City of Redwood City travel demand model was developed from the C/CAG model as a part of the City's new <br />Draft General Plan. The City's model is designed to project vehicular traffic volumes for the local arterials and <br />collector roadways caused by local land use changes. The City of Redwood City model is a sub-area model of the <br />C/CAG model. Therefore, the City's model has less detail in the areas outside of the City, but includes much <br />greater detail in terms of the local roadway network and the distribution of land uses within the City. The City's <br />model does not have a mode choice model nor does it include a transit network for estimating transit ridership. <br /> <br />Because neither of these models were intended for use to evaluate the Saltworks project, they do not contain all <br />the features needed to evaluate this type and scale of development. The City's model lacks sufficient regional <br />detail to evaluate the Saltworks connections to jobs in nearby and surrounding communities and the C/CAG <br />model does not have sufficient detail within the City to fully assess the changes in travel patterns on the local <br />roadways. In addition, neither model has a calibrated mode choice model and transit component, which would be <br />needed to evaluate the potential ridership of the circulator or streetcar system and employee-based bus service <br />proposed for the project. For a project of this scale, it would be imperative that any transportation analysis use a <br />validated model for the City of Redwood City and the Peninsula region. This model would typically be developed <br />from one of the two available models by including the needed network detail and mode choice element. <br /> <br />3.2 PRELIMINARY FORECASTS FOR THE SAL TWORKS PROJECT <br /> <br />DMB used both of the available models to perform preliminary demand estimates for the Saltworks to understand <br />the general changes in travel patterns and order-of-magnitude traffic volumes using the major links connecting the <br />project to the local and regional transportation systems. Fehr & Peers reviewed these preliminary results, which <br />were helpful in identifying potential travel pattern changes that could occur with the introduction of such a large <br /> <br />8 <br />