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SIGNALIZED INTERSECTIONS The following criteria are used to evaluate the potential significance of LOS impacts at signalized intersections: _ Intersections on freeways/state facilities LOS D Intersections on gateway roadways LOS D _ Intersections on county roadways LOS C Intersections on Mountain House CSD streets LOS C City of Tracy planning area within V4 mile of I-205 LOS D Grant Line Road in Alameda County LOS D In this section,the LOS analysis is conducted based on peak-hour intersection LOS as defined in the 2000 Highway Capacity Manual(Transportation Research Board 2000). A description of the LOS analysis - methodology is provided in Table 4.114. Table 4.11-4 - Level-of-Service Criteria for Signalized Intersections Level of Control Delay/ Service Type of Flow Delay Maneuverability Vehicle _ (s/veh) A Stable Very slight delay.Progression is very Turning movements are easily < 10.0 Flow favorable,with most vehicles arriving during made,and nearly all drivers the green phase and not stopping. find freedom of operation. B Stable Good progression and/or short cycle lengths. Vehicle platoons are formed. > 10-20 Flow More vehicles stop than for LOS A,causing Many drivers begin to feel _ higher levels of average delay. somewhat restricted within groups of vehicles. C Stable Flow Higher delays resulting from fair progression Back-ups may develop behind >20-35 _ and/or longer cycle lengths.Individual cycle turning vehicles.Most drivers failures may begin to appear at this level.The feel somewhat restricted. number of vehicles stopping is significant, although many still pass through the - intersection without stopping. D Approaching The influence of congestion becomes more Maneuverability is severely >35-55 Unstable noticeable.Longer delays may result in some limited during short periods due - Flow combination of unfavorable progression,long to temporary back ups. cycle lengths,or high volume-to-capacity ratios.Many vehicles stop,and the proportion of vehicles not stopping declines.Individual cycle failures are noticeable. E Unstable Generally considered to be the limit of There are typically long queues >55-80 Flow acceptable delay.Indicative of poor of vehicles waiting upstream of progression,long cycle lengths,and high the intersection. volume-to-capacity ratios. Individual cycle failures are frequent occurrences. F Forced Flow Generally considered to be unacceptable to most Jammed conditions.Back ups >80 drivers.Often occurs with oversaturation.May from other locations restrict or also occur at high volume-to-capacity ratios. prevent movement.Volumes _ There are many individual cycle failures.Poor may vary widely,depending progression and long cycle lengths may also be principally on the downstream major contributing factors. back-up conditions. Source: Transportation Research Board 2000 and Highway Research Board 1965 EDAW College Park at Mountain House Specific Plan III Draft EIR - Transportation 4.11-16 San Joaquin County