AgdaPkt 2017-09-11 Closed and Joint SA PFA

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TA. - Page 111 LSA ASSOCIATES, INC. ROCKETSHIP REDWOOD CITY ELEMENTARY SCHOOL PROJECT SEPTEMBER 2016 INITIAL STUDY/MITIGATED NEGATIVE DECLARATION Table 6: Intersection Level of Service Criteria Signalized Unsignalized Intersection Intersection Level of Average Average Service Control Delay Control Delay OS Description seconds/vehicle seconds/vehicle Little or no traffic delay:Signal progression is extremely favorable. A Most vehicles arrive during the green phase and do not stop at all. <10.0 _<10.0 Short cycle lengths may also contribute to the very low vehicle delay. Short traffic delays:Operations characterized by good signal B progression and/or short cycle lengths.More vehicles stop than with 10.1-20.0 10.1—15.0 LOS A,causing higher levels of average vehicle delay. Average traffic delays:Higher delays may result from fair signal progression and/or longer cycle lengths.hidividual cycle failures may C begin to appear at this level.The number of vehicles stopping is 20.1-35.0 15.1-25.0 significant,though may still pass through the intersection without stopping- Long to in .Long traffic delays:The influence of congestion becomes more noticeable.Longer delays may result from some combination of D unfavorable signal progression,long cycle lengths,or high volume-to- 35.1—55.0 25.1-35.0 capacity(V/C)ratios.Many vehicles stop and individual cycle failures are noticeable. Very long traffic delays:This is considered to be the limit of acceptable delay.These high delay values generally indicate poor E 55.1-80.0 35.1-50.0 signal progression,long cycle lengths,and high volume-to-capacity /C ratios.hidividual cycle failures occur frequently. Extreme traffic delays:This level of delay is considered unacceptable by most drivers.This condition often occurs with oversaturation,that F is,when arrival flow rates exceed the capacity of the intersection.Poor >80.0 >50.0 progression and long cycle lengths may also be major contributing causes of such delay levels. Source: Transportation Research Board,2000 Highway Capacity Manual(Washington,D.C.). All intersection LOS were calculated using the methodology approved by the C/CAG,which utilizes the 2000 Highway Capacity Manual(HCM)methodology for both signalized and unsignalized intersections. For signalized intersections,LOS is evaluated on the basis of average control delay time (measured in seconds per vehicle) for all vehicles at the intersection. For unsignalized stop-controlled intersections,LOS is evaluated based on the average delay experienced by vehicles that must stop or yield to on-coming traffic.For unsignalized all-way stop controlled intersections,LOS is determined by the average delay for all movements through the intersection. Level of Service Standards. Criteria used to determine impacts on intersections are based on the City of Redwood City and County of San Mateo level of service standards,as discussed below. City of Redwood City. According to the City of Redwood City, a significant impact would occur if project development would cause: 1. Operations at a signalized intersection to deteriorate from an acceptable level(LOS D or better)to an unacceptable level(LOS E or F); or 2. Average delay at a signalized intersection operating at an unacceptable level(LOS E or F) to increase by five seconds or more. P:1RWC1401B Rocketship Sch-I\PRODUCrSUS-MND1Public\Ra ketship Public Review 09-29-16.docx(09/29/16)PUBLIC REVIEW DRAFT 87 ATTY/RESO.0084/CC RESO ADOPTING CEQA-ROCKETSHIP CHARTER SCHOOL APPEAL REV:09-05-17 VR Page 95 of 124