13 ATTACHMENT 11 - Laserfiche WebLink

Josh Pack PP November 10, 2009 Page5of8 II it & PFPR< IRAMSVOXl AI10 ' ( DXSULIASIS Project traffic from the retail components of the project (Table 1) were assigned to the roadway network based on the above percentages and added to the Near -Term Without Project traffic forecasts presented in the June 2009 report. The applicable pass -by trips were also added to the Bernal Avenue /Koll Center Drive and Bernal AvenueNalley Avenue intersection. The resulting traffic forecasts are shown on Figure 2 and will be used as the basis for the updated analysis. ANALYSIS METHODS AND RESULTS This analysis was conducted using the software analysis tool Synchro 6.0 and SimTraffic, which calculates delay based on methods outlined in the 2000 Highway Capacity Manual (HCM). The HCM method calculates control delay at an intersection based on inputs such as traffic volumes, lane geometry, signal phasing and timing, pedestrian crossing times, and peak hour factors. The HCM method was used to identify significant project impacts, while SimTraffic, a micro - simulation software, was used to account for the effects of vehicle queue spillback, lane utilization as vehicles position themselves to enter the freeway, and the operation of trap lanes, such as the ones on Bernal Avenue. These analysis methods are identical to those used in the June 2009 study. Traffic signal timing through the corridor was optimized and the intersection off -sets were selected to balance vehicle queues through the corridor and provide good vehicle progression on Bernal Avenue. Intersection Geometries The lane configurations assumed at each study intersections is shown on Figure 2 and described below: • Bernal Avenue /I -680 Southbound Ramps — Signalization of the intersection • Bernal Avenue /I -680 Northbound Ramps — No improvements • Bernal Avenue /Koll Center Drive — construction of an eastbound right -turn only lane, a westbound left -turn only lane, as well as a northbound left-turn and right -turn lane exiting the site; no changes to the north leg of the intersection. • Bernal AvenueNalley Avenue intersection — conversion of the eastbound right -turn only lane to a through -right shared lane. Level of Service Results Results of the level of service assessment are presented in Table 3, and compared to the results presented in the June 2009 report. The level of service results show that with the volumes and lane configurations shown on Figure 2, the study intersections are projected to operate at an acceptable service level (i.e. LOS D or better). No additional improvements would be required on opening day of the Proposed Project to mitigate the off -site project impacts along the project frontage. Vehicle Queuing Vehicle queues were evaluated for the movements on Bernal Avenue with the Proposed Project, as presented in Table 4. The average vehicle queue as well as the 95th percentile vehicle queue is presented. The average vehicle queue is generally representative of conditions during the peak hour, although the 95th percentile vehicle queue could be reached several times during the peak hour, potentially impacting adjacent intersections for several signal cycles.