Common use of Traffic Queue Length Clause in Contracts

Traffic Queue Length. We manually counted the traffic queue lengths from field recorded video tapes. Because of time constraints, this analysis was conducted on two representative intersections on the SR 99 corridor. Table 9-8 shows the statistics for traffic queue lengths on the cross-streets of the two intersections. 164th Street Eastbound 4.412 2.377 12 4 174th Street Westbound – through 1.353 1.433 5 1 174th Street Westbound – Left turn 0.647 0.597 2 1 174th Street Eastbound– through 0.800 1.476 8 0 174th Street Eastbound– Left turn 3.983 2.344 12 4 TSP On 164th Street Westbound 4.471 3.229 13 3 164th Street Eastbound 3.829 2.172 10 4 174th Street Westbound– through 1.909 1.258 6 2 174th Street Westbound– Left turn 0.338 0.553 2 0 174th Street Eastbound– through 1.722 1.944 9 1 174th Street Eastbound– Left turn 3.654 2.591 10 4 As we can see in Table 9-8, when TSP was turned on, queue length decreased in some cases and increased in other cases. This is reflected by the unpredictable changes in queue length statistics, including standard variation, maximum queue length, and median queue length, in Table 9-8. Again, a paired t-test was applied to compare the average queue lengths at the test intersections before and after TSP implementation. The t ratio was -1.663, the absolute value of which was smaller than the critical t ratio of 1.962 at p=0.05. Therefore, the change in average queue lengths on cross-streets after the SS- RTSP implementation was not significant.