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City of Santa Ana -Park View at Town and Country Manor <br />Draft EIR <br />and Traffic <br />Table 4.6.1 (cont.): Level of Service Descriptions for Signalized Intersections - ICU <br />Methodology <br />Level of <br />Service <br />ICU Value <br />0.61-0.70 <br />Description <br />Very good operation. This represents stable flow. Many drivers begin to feel <br />B <br />< 10.0 <br />B <br />somewhat restricted within platoons of vehicles. An approach to an <br />Short traffic delays <br />C <br />intersection may occasionally be fully utilized and traffic queues start. <br />C <br />0.71-0.80 <br />Good operation. Occasionally drivers may have to wait more than 60 seconds, <br />Long traffic delays <br />and back -ups may develop behind taming vehicles. Most drivers feel <br />somewhat restricted. <br />D <br />0.81-0.90 <br />Fair operation. Cars are sometimes required to wait more than 60 second <br />during short peaks. There are no long - standing traffic queues. This level is <br />typically associated with design practice for peak periods. <br />E <br />0.91-1.00 <br />Poor operation. Some long - standing vehicular queues develop on critical <br />approaches to intersections. Delays may be up to several minutes. <br />F <br />Over 1.00 <br />Forced flow. Represents jammed conditions. Back -up from locations <br />downstream or on the cross street may restrict or prevent movement of <br />vehicles out of the intersection approach lanes. <br />Source: Traffic Impact Study and Parking Analysis for the Park View at Town & Country Manor, Kimley -Horn <br />Associates, Inc., June 2009. <br />Signalized Intersections - Highway Capacity Manuel (HCM) Methodology <br />In accordance with Caltrans Traffic Impact Study Guidelines, all intersection controlled by Caltrans, <br />such as signalized intersections at freeway ramps, were analyzed using the Highway Capacity Manual <br />(HCM) 2000 methodology. The HCM methodology estimates the average delay (in average second <br />per vehicle) for each of the movements through the intersection, depending on a number of factors, <br />including number of lanes, volume of traffic, and signal timing. Just as with the ICU methodology, <br />the HCM delay forecast translates to a Level of Service designation, ranging from LOS A to LOS F. <br />The descriptions of operating conditions for each Level of Service are similar to the LOS descriptions <br />for the ICU methodology. A summary description for each Level of Service for the HCM signalized <br />intersection methodology, and the corresponding delay, expressed in seconds per vehicle, is provided <br />below in Table 4.6 -2. <br />Table 4.6.2: Level of Service Descriptions for Signalized Intersections - HCM Methodology <br />Level of <br />Service <br />Delay <br />I (second /vehicle ) <br />Description <br />Little or no delay <br />A <br />< 10.0 <br />B <br />> 10.0 - 20.0 <br />Short traffic delays <br />C <br />> 20.0 - 35.0 <br />Average traffic delays <br />D <br />> 35.0 - 50.0 <br />Long traffic delays <br />Michael Brandman Associates 4.6 -3 <br />H\Cl t(PN- JMb327b32]003MHRb32]0030 Sec0 Tmspo md¢ <br />