AgdaPkt 2017-09-11 Closed and Joint SA PFA

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TA. - Page 192 Traffic Analysis Review of Proposed Rocketship Charter School,Redwood City, CA Introduction This letter report summarizes the findings of PRISM Engineering regarding the traffic impact study prepared by Hexagon, as well as our observations in the field of real world traffic and parking, etc., and concerns as it relates to school uses in this industrially zoned area. Existing Conditions and Surroundings The intersection of Woodside Road (SR 84) at Bay Road calculates to LOS C conditions using the Highway Capacity Manual (HCM) 2010 methodology. PRISM Engineering counted the traffic turning movements at this location, and ran the industry standard HCM analysis using Synchro software. This similar calculation result was shown in Table 3 of the Hexagon traffic impact study for the project. This calculation would be correct if it were not for the fact that this intersection is only 600 feet away from another intersection, Woodside at Broadway which is also at LOS F conditions (calculated as LOS E in a vacuum). LOS F conditions also exist at the US 101 freeway ramp intersections. This LOS F condition at the freeway ramps translates back all the way to the Bay Road intersection, and beyond, as observed in the field. There is actually an observable LOS F condition at the Woodside and Bay Road intersection during the am peak hour because of blockage of traffic backing up from the US 101 interchange. This results in the northbound traffic on Woodside having a stop and go condition. Traffic does not freely flow through this intersection. I observed in the field while counting the traffic at Woodside and Bay that the northbound approach was at LOS F conditions because of this, and that the northbound approach was 42%of the total traffic at this intersection. Because the intersection is so close to Broadway and also to the US 101 freeway ramp intersections, these can only be accurately calculated using a traffic operations microsimulation methodology,which was beyond the scope of our study(this would require much more data collection for all intersections, and the building of a microsimulation model). In the CALTRANS GUIDE FOR THE PREPARATION OF TRAFFIC IMPACT STUDIES, it specifically stipulates that the only kind of traffic analysis that is correct for closely spaced intersections on its surface street facilities is detailed microsimulation analysis, which was NOT done in the GUIDE FORT"IIF:PREPARATION Hexagon traffic analysis. Caltrans states: OF TRAFFIC TNIPACT STI-DIS "When a State highway has saturated flows, the use of a micro-simulation model is encouraged for the analysis" I can definitively state that, based on my actual observations of traffic operations of this intersection in the field during the am peak hour, that LOS F conditions are significantly present. 42% of the traffic (the northbound approach) are delayed significantly, and waiting more than one signal cycle to get through. This is an LOS F condition, and especially -OW , "PRISM'-' Page 2 � � •,,i ENGINEERING s