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ATTACHMENT D In 2002 a staff team evaluated red light photo-enforcement. The staff report from that process is attached. The cost of the enforcement camera system, associated administrative and court costs of citation processing and uncertainty about public acceptance contributed to the recommendation to delay implementation of a red light running camera program. The biennial review process has been completed and highlights of the cost and public acceptance reported for Portland, Medford and Beaverton are given above. The May 11, 2005 update on Photo red light cameras is also attached. Staff continues to recommend delay in red light camera implementation until after the AIRS upgrade anticipated in FY08. ALL RED PHASING All red phasing is often used in wider intersections to allow additional clearance time. The added red time also gives red light violators extra time to cross the intersection safely. The most recent studies show an all red phase of 1.5 to 2 seconds does reduce the number of crashes associated with red light violations. A limited number of Eugene intersections already have one or two seconds of all red. We have not implemented all red as a standard practice. The difficulty with all red phasing is the associated increase in congestion and reduction of capacity at congested intersections. For most of our simple downtown two phase (north-south and east-west) intersections adding 1.5 seconds of all red will reduce the green time by just over 4%. For the fixed time signal network downtown, all red phasing would show little benefit and increase congestion. At more complicated intersections with left turns or separated phasing the capacity reduction will be greater. During rush hour we have capacity and congestion problems in several corridors. All red phasing will make these problems worse. At signals that have vehicle detection, outside of peak hours, the increase in congestion will not present a capacity issue. Traffic Operations staff are currently analyzing several intersections and will continue to add all red phasing when intersection geometry, crash history, length of intersection crossing and impact on traffic progression make all red appropriate. YELLOW CLEARANCE INTERVAL The City of Eugene uses a minimum 4.0 yellow change interval for all signals with approach speeds 40 MPH and under. This builds in a buffer of yellow time and represents an existing extension of yellow time beyond established minimums. The Manual of Traffic Signal Design calculates a value of 3.2 seconds for a 30 MPH signal approach. We have rounded up the yellow interval for all the downtown signals and other signals on 30 MPH roads by at least 25% or 0.8 seconds. In comparison, the City of Beaverton uses 3.5 seconds at photo-enforced streets with 30 MPH approach speeds. At speeds of 35 MPH and 40 MPH Beaverton uses 4.0 second yellow interval. Extending the yellow interval too much leads to poor compliance as the driver who reached a complete stop on yellow may be tempted to continue through the next yellow indication. Excessive yellow will also reduce available green time similar to an all red phase. Page 2 of 3