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. 11111 fp FEHR&PEERS ASSOCIAI l✓S,INC. Transportation Consultants Ms. Dolores Ortiz January 14, 2000 Page 3 of 6 The trip distribution for the proposed project is based on existing traffic patterns. The trip distribution and the project trip assignment are presented in Figure 5. TRAFFIC ANALYSIS Fehr & Peers Associates analyzed intersection operations at the four study intersections during both morning and evening peak hours under two different scenarios: Existing Conditions and Existing Plus Project Conditions. In order to measure and describe the operation of a local roadway network, traffic engineers and planners commonly use a grading system called Level of Service (LOS). The LOS grading system qualitatively characterizes traffic conditions associated with varying levels of traffic flow. These levels range from LOS A, which indicates free-flow traffic conditions with little or no delay experienced by motorists, to LOS F, which describes congested conditions where traffic flows exceed design capacity, resulting in long queues and delays. Table 2 presents level of service definitions for both signalized and unsignalized intersections. For this study, the 1994 Highway Capacity Manual methodology for signalized and unsignalized intersections was used. Figure 6 illustrates the intersection turning volumes for the Existing Plus Project Conditions. The service level summaries for both Existing Conditions and Existing Plus Project Conditions are presented in Table 3. Under Existing Conditions, the two signalized intersections operate at acceptable LOS C or better during morning and evening peak hours. Normally, total intersection delay and levels of services would be presented for the unsignalized intersection, but at the subject unsignalized ramp intersections, all movements except the left turns are uncontrolled and experience no delays. The left-turn movements at the unsignalized intersections of Marina Boulevard with 1-880 on-ramps operate at acceptable LOS D during the AM peak hour, and not-acceptable LOS F during the PM peak hour. The addition of traffic from the proposed project results in marginal increases in delays at the study intersections, however all intersections continue to operate at the same service levels as without the project. Since the project does not produce any eastbound left-turns at the Marina Boulevard/I-880 Northbound On-Ramp intersection, there are no significant impacts at this intersection. The project contributes 21 vehicles to the already failing westbound left- turn at the Marina Boulevard / I-880 Southbound On-Ramp during the evening peak hour. This is less than five percent of the existing left-turn volume, and is not considered a significant impact. 4I3