Item B: West 11th Transportation Corridor Study

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Mobility Standards Agency mobility standards often require intersections to meet level of service (LOS) or volume-to-capacity (V/C) intersection operation thresholds. All twenty-two study intersections are located within the Eugene- Springfield Metropolitan Area. Eight are on Oregon Department of Transportation (ODOT) facilities classified as Statewide Highways (OR 99 and OR 126), and the other fourteen are under City jurisdiction. According to the 1999 Oregon Highway Plan (OHP), ODOT mobility standards are given as V/C ratios 12 and are based on the highway category. For the City of Eugene, all intersections outside the Central Area Transportation System (CATS) area must meet a Level of service D standard. Brief definitions of the two types of mobility standards are provided below, followed by Table 3-3, which shows the applicable mobility standards of the study intersections. The intersection level of s of service A, B, and C indicate conditions where traffic moves without significant delays over periods of peak hour travel demand. Level of service D and E are progressively worse operating conditions. Level of service F represents conditions where average vehicle delay has become excessive and demand has exceeded capacity. This condition is typically evident in long queues and delays. The volume-to-capacity (V/C) ratio represents the level of saturation of the intersection or turning movement and is given as a decimal. It is determined by dividing the peak hour traffic volume by the maximum hourly capacity of an intersection or turn movement. When the V/C ratio approaches 1.0, operations become unstable and small disruptions can cause the traffic flow to break down, as seen by the formation of excessive queues. Table 3-3: Applicable Study Intersection Mobility Standards Major Roadway Jurisdiction (Category) Mobility Standard thth W 6 and W 7 Avenues ODOT (Statewide HWY) th W 11 Ave (west of Beltline Rd) ODOT (Statewide HWY Freight Route) th W 11 Ave (east of Beltline Rd) City of Eugene LOS D or better th W 13 Ave City of Eugene LOS D or better Existing Intersection Performance The existing operation performance of the study intersections was performed using Synchro software. 13 employs methodology from the 2000 Highway Capacity Manual. The traffic volumes and transportation system configurations described previously were used to determine intersection levels of service and volume-to-capacity ratios. Intersection signal timing was obtained from the City of Eugene and also used in the analysis. The resulting operations analysis is presented in Table 3-4. 12 1999 Oregon Highway Plan, Oregon Department of Transportation, 1999; Table 6 in Policy 1F displays the maximum allowable V/C ratios for areas outside of the Portland Metropolitan Area. 13 2000 Highway Capacity Manual, Transportation Research Board, Washington, D.C., 2000. th West 11 Avenue Corridor Study September 4, 2009 City of Eugene P07265-003-000 14