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;i These inflated Vernalis Interchange EIR forecasts were used to evaluate cumulative traffic conditions for this EIR. E . i Level of Service (LOS) Definitions Levels of service have been defined to measure the flow of traffic on various types of roadways. Levels of service range from LOS A to LOS F, with LOS A representing unimpeded flow and LOS F representing extreme traffic congestion. i i) At unsignalized intersections, LOS criteria are defined in terms of total delay, or elapsed time from when a vehicle stops at the end of a queue until the vehicle departs from the I stop line. - This.time includes the time required for the vehicle to travel from the last-in- li queue position to the .first-in-queue position. The average total delay for any particular minor movement is dependent upon the capacity of the approach, the number of vehicles I� at the approach, and the availability of gaps in the major street traffic stream. LOS F exists ;w .' when there are insufficient gaps of suitable size to allow a side street demand to cross safely into or through the traffic on the major street. The LOS definitions for unsignalized intersections are shown in Table 4.4-1. � f Table 4.4-1: Traffic Level Of Service Definitions At Unsignalized Intersections it Level of Service Average Delay A Up to 5 sec. s 4 B >5 to 10 sec. C >10 to 20 sec. D >20 to 30 sec. E >30 to 45 sec. >45 ==J ). .� Source: Transportation Research Board, 1994. i it Levels of service on roadway segments are defined in terms of the volume to capacity ratio for a given segment. The capacity of a roadway segment is the service flow rate, which is the ideal capacity adjusted to take into consideration specific geometric features such as grades and other geometric constraints, and the characteristics of traffic such as the E percent of trucks and temporal variations in traffic density. i f Levels of service on ramp junctions and weaving sections are defined in terms of the speed at which traffic can navigate through these special freeway sections. The speeds of traffic already on the freeway and traffic using the freeway ramps are both considered in �f developing levels of service for these sections. ' Trip Generation i Traffic operations were analyzed for the AM peak hour (6:00-8:00 Ann) using the 1994 Highway Capacity Manual operations method. Because of the operating characteristics Draft Environmental Impact Report 4-41 ER-96-3 l I�