Loading...
HomeMy WebLinkAboutAccess Point Analysis-136th & Keystone Ave STEVEN J. FEHRIBACH, P.E. PRESIDENT R. MATTHEW BROWN, P.E. VICE PRESIDENT KAREN K. COLLINS, P.E. VICE PRESIDENT JOSEPH T. RENGEL, P.E. VICE PRESIDENT 8365 KEYSTONE CROSSING, SUITE 201 – INDIANAPOLIS, INDIANA 46240 TELEPHONE (317) 202-0864 – WWW.AF-ENG.COM TRANSPORTATION ENGINEERING STUDIES ● TRAFFIC IMPACT ANALYSES STREET DESIGN ● HIGHWAY DESIGN ● TRAFFIC ENGINEERING PARKING LOT DESIGN ● TRANSPORTATION PLANNING STUDIES CONSTRUCTION OBSERVATION ● SITE ENGINEERING REGISTRATION INDIANA ILLINOIS KENTUCKY MICHIGAN OHIO MISSOURI TEXAS MEMORANDUM DATE: MARCH 18, 2020 TO: MIKE GOULD EPCON COMMUNITIES FROM: STEVEN J. FEHRIBACH, P.E. PRESIDENT RE: BRENNAN PROPERTY ACCESS POINT ANALYSIS The purpose of this analysis was to determine if a left turn treatment located east of Keystone Avenue on 136th Street would adequately serve the proposed single-family subdivision. Trip Generation Analysis In order to determine how many vehicles would enter and exit the site, a trip generation analysis was conducted. The proposed site has 169 homes. This development would be occupied by empty-nester homes and be limited to home buyers age 55 and over. The trip generation manual published by the Institute of Traffic Engineers (ITE) was used to calculate the number of trips generated by the development. The following table is a summary of the trips that will be generated by the development for the AM peak hour and PM peak hour. Traffic Generation Summary Land Use AM Peak Hour PM Peak Hour Entry Exit Entry Exit Senior Adult Housing – 169 Homes 20 41 44 28 Single Family-169 Homes 31 94 106 62 Percent Decrease 64% 44% 41% 45% Assignment and Distribution The projected trips for the site must be assigned and distributed to the existing street system so that the access volumes can be determined. The assignment and distribution is based on existing traffic volumes, the projected land uses, and the location of the access point. It was calculated that the majority of the traffic (75%) will come from the west and make a left turn into the site. This volume will be used to determine if/what type of improvements on 136th Street would be necessary to mitigate any capacity issues at the access point. Capacity Analysis In order to determine what improvements are necessary and how the access will function once those improvements are implemented, a capacity analysis of the proposed access point and 136th Street was conducted. An analysis was completed with the addition of an eastbound left turn lane into the site, and an analysis was completed without an eastbound left turn lane. The purpose of comparing the two alternatives was to determine if the queue of vehicles would extend into the interchange at Keystone Avenue and 136th Street. Conclusions The conclusions that follow are based on the trip generation analysis and capacity analysis that were conducted for the site. • Based on the fact that the development will be limited to buyers age 55 and over it can be seen through the trip generation analysis that the number of vehicles that will be generated during the AM peak hours and PM peak hours will be minimal. • Based on the trips generated calculations for single-family residents, it can be seen that a standard single-family dwelling unit would generate significantly more trips during the AM and PM peak hours. • Based on the capacity analysis, it was determined that with an added left turn lane at the access point for the eastbound to northbound generated trips, the eastbound approach will operate at a high level of service. The level of service will be for the AM peak hours and for the PM peak hours. • Based off the queue length analysis, it was also determined that the projected queue for the east bound to northbound left turn movement would be 35’ for the AM peak hours and 43’ for the PM peak hours. Based on this analysis, it can be seen that with the left turn lane alternative, the projected queue will not back up into to the interchange. • Based on a field review of the northbound off ramp, it was determined that the majority of the vehicles in the PM peak hours are wanting to proceed east on 136th Street. Those vehicles are delayed by vehicles wishing to go westbound through the interchange. Recommendations Based on the analysis and the conclusions that have been reached, the following recommendations are provided. The access point should be designed and developed as follows: • The southbound approach should be developed as a two-lane approach with one outbound lanes and one inbound lane. The inbound lane should be developed with a minimum of 14 feet width. • 136th Street should be designed and constructed with an eastbound to northbound left turn lane. This lane should be constructed from the proposed access point back to the roundabout of 136th Street and Keystone Avenue. • Based on the fact the northbound off ramp is working at or over capacity, an additional northbound land should be added to allow vehicles to maneuver to the southbound lane on 136th Street.