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III. ENVIRONMENTAL SETTING IMPACTS AND MITIGATION MEASURES C. TRAFFIC CIRCULATION AND SAFETY TABLE III.0-2 LEVEL OF SERVICE CRITERIA FOR SIGNALIZED INTERSECTIONS Level of Volume/Capacity Service Typical Operating Characteristics (v/c)Ratio A Level of Service A describes a condition where the approach to an 0.00-0.60 intersection appear quite open and turning movements are made easily. Little or no delay is experienced. No vehicles wait longer than one red traffic signal indication. The traffic operation can generally be described as excellent. B Level of Service B describes a condition where the approach to an 0.61-0.70 intersection is occasionally fully utilized and some delays may be encountered. Many drivers begin to feel somewhat restricted within groups of vehicles. The traffic operation can generally be described as very good. C Level of Service C describes a condition where the approach to an 0.71-0.80 intersection is often fully utilized and back-ups may occur behind turning vehicles. Most drivers feel somewhat restricted,but not objectionably so. The driver occasionally may have to wait more than one red traffic signal indication. The traffic operation can generally be described as good. D Level of Service D describes a condition of increasing restriction causing 0.81-0.90 substantial delays and queues of vehicles on approaches to the intersection during short times within the peak period. However,there are enough signal cycles with lower demand such that queues are periodically cleared, thus preventing excessive back-ups. The traffic operation can generally be described as fair. E Level of Service E describes a condition at which capacity of the intersection 0.91-1.00 is reached;i.e., it represents the most vehicles that any particular intersection can accommodate. At capacity there may be long queues of vehicles waiting upstream of the intersection and vehicles may be delayed up to several signal cycles. The traffic operation can generally be described as poor. F Level of Service F represents a jammed condition. Back-ups from locations 1.01+ downstream or on the cross street may restrict or prevent movement of vehicles out of the approach under consideration. Hence,volumes of vehicles passing through the intersection vary from signal cycle to signal cycle. Because of the jammed condition,this volume would be less than capacity. SOURCE: Environmental Science Associates,from Transportation Research Circular No. 212,Transportation Research Board, 1980. Stockton Scavenger Transfer Station Expansion III.0 3 ESA/990190