2015-09-01 P & Z Packet - Laserfiche WebLink

Home Browse Search

tY, Jane Rose October 16,2007 Jack Corkle Page 3 • In reviewing the CSAH 14 Study that was completed by SRF, the intersection of CSAH 14/20th Avenue was found to operate at an unacceptable LOS E during the p.m.peak hour under all-way stop control. The Centerville EAW traffic analysis documented that this intersection is operating at LOS C during this time period. In comparing the intersection turning movements, the volumes increased during both the a.m. and p.m. peak periods between 2004 and 2007, which would indicate similar or worse operations. Due to the discrepancy, analysis was,,completed for this intersection with the current traffic volumes and all-way stop control using the Highway Capacity Software and Synchro/SimTraffic software package. Based on this analysis, we found this intersection to operate at an overall unacceptable LOS E during the p.m. pear hour. This intersection should be checked to ensure that adequate capacity is provided for existing and future [ conditions. r - • The 2012 operations analysis assumed upgrades to the CSAH 14 corridor that are scheduled to be completed in 2009, including signalization of CSAH 14/20th Avenue and f widening CSAH 14 to improve the 90-degree curve just west of the intersection with F CSAH 21 (Centerville Road). No additional improvements are recommended. Based on the CSAH 14 roadway design plans that will be constructed next year, the southbound approach of 20th Avenue at CSAH 14 should consist of dual left-tum lanes, one through lane, and a shared through/right-tum lane. It appears that this study analyzed this approach with dual left-turns lanes, one through lane, and a right-tum lane. Although this will not significantly impact operations, the correct future geometries should be noted in the study. In addition, the geometries shown on this approach are not consistent throughout the report for 2030 conditions. Based on the operations analysis shown in the h appendix of the report,dual southbound left-tum lanes were included. r • For 2030 conditions, the roadway upgrades identified for 2012 conditions are assumed as a baseline. However, the improvements were recommended to be modified to improve safety. The modified improvement includes the installation of a northbound left-tum lane instead of a right-tum lane at the intersection of CSAH 14/Centerville Road. In addition, installation of a southbound left-tum lane is recommended at this intersection, with future signalization,to align the left-tum lanes on the north and south approaches. Installation of a southbound right-turn lane at CSAH 14/Progress Road is also recommended. Based on our analysis, the suggested modifications to the roadway geometries will not change the overall intersections 9perations, and it may provide some additional safety for the intersections and flexibility in providing future left-tum phasing. In regards to the southbound right-tum lane at Progress Road/CSAH 14, this improvement does not significantly improve operations or safety, based on our review. If the right-of-way is available to construct a right-tum lane on this approach, it would provide some delay reduction to that individual movement.