3C Public Hearing 2010 0503 - Laserfiche WebLink

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TJIQ~+t Transporbtticn Consulmnts Traffic Impact Fee Analysis TJKM obtained the San Leandro Traffic Model from the City of San Leandro with an approval from the Alameda County Congestion Management Agency (ACCMA). The City's model is derived directly from the ACCMA countywide model; this is the current model being used for the preparation of a DEIR for the ICI/Kaiser Permanente development in the southwest quadrant of the interchange. It generates peak hour trips for existing year and 2030 forecasting years. TJKM reviewed the network to make sure there are no errors or omissions. Likewise, TJKM reviewed the land use data, especially with an eye towards the land use categories of the DFSI program at the city. Since there are many land use categories, we chose to use specific land use categories in the DFSI program where each one is identified with an tTE land use code. Total Trips Using the Interchange A process called "select link analysis" was used within the ACCMA countywide model. The roads in the model are called "links" that extend between two "nodes" (intersections). All links comprising Marina Boulevard between Merced Street and Teagarden Street plus all links comprising the on and off ramps (but not the I-880 mainline) were defined as selected for the model runs for 2005 and 2030. This analysis essentially tabulated all trips assigned to the selected links and also categorized these trips as having an origin or destination somewhere within San Leandro and those that do not. A simple process of subtraction was used to define trips created by development within San Leandro and increases due to through traffic. The overall growth was also derived through simple subtraction. Figure 2 on the next page graphically shows model output for the select link analysis. The width of the line along a street is proportional to the total number of trips, with the wider the line, the more the trips. Trips along the I-880 mainline are shown, but as can be seen, all mainline trips use the ramps, and no through traffic along I-880 is shown in the graphic. The estimated total of all trips using the interchange during the a.m. and p.m. peak hours is 14,814 on a typical weekday in 2030. In 2005 this total is 7,924, so the increase over 25 years is 87 percent, or about a 2.5 percent increase per year, on average. Trips using the interchange with an origin and/or destination within the city are 97 percent of all trips in 2005 and 88 percent of all trips in 2030. The reason for the increased through traffic at the interchange is due to anticipated congestion in I-880. More trips between Oakland west of I-880 are likely to use Doolittle Drive to bypass the I-880 Davis Street interchange and get on at Marina to avoid I-880 congestion north of Marina Boulevard, and there are also other trip patterns where regional traffic stays on surface streets to avoid I-880 congestion in the peak hours. The main consideration, however, is that traffic at the currently-congested interchange is expected to increase by 87 percent. Clearly, capacity improvements are needed. Table II shows 2005 and 2030 trip origins/destinations using the interchange in the combined a.m. and p.m. peak hours. Table 11: Total Trips Using the Interchange by Locations Year Allocation Trips % Total Growth % Total Growth 2005 City Only 7,687 97% , , Total 7,924 2030 City Only 12,989 88% 5,302 41 Total 14,814 6,890 47% Page 8 Final Re¢ort - Tragic Im¢act Fee Analysis for 1-880/Marino Interchange Improvement November 12, 2009