19 - TxDOT Safety Capital Improvement Project Raised Median - Lamar Avenue

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Lamar Avenue (US 82) Raised Median Narrative The proposed safety enhancement at this location consists of constructing a raised median from 33rd Street to 42nd Street and resurface. Some road widening would also need to be performed at the intersections of 33rd Street, Wal-Mart Entrance, and 42nd Street to better accommodate U- turn maneuvers at these intersections. The estimated cost for this work is $2,046,230.46. The Safety Improvement Index (cost benefit ratio) of this project is 4.55. This corridor has an ADT of 21,817 vehicles per day and an access density (23 south & 17 north) of 55 accesses per mile. Per TxDOT's "Roadway Design Manual", where ADT exceeds 20,000 vehicles per day or where development is occurring, and volumes are increasing and are anticipated to reach this level, and the demand for mid -block turns is high, a raised median design should be considered. For these conditions, a raised median may improve safety by separating traffic flows and controlling left -turn and crossing maneuvers. Some potential benefits of this enhancement include: restricting left -turn and crossing maneuvers to specific locations or certain movements, improve traffic safety, increasing through capacity and reducing delays, and providing pedestrian refuge areas. From 2017 through 2019, 8 accidents have occurred resulting in 1 serious injury and 7 non -incapacitating injuries due to left turn maneuvers. The previously noted accidents are directly related to vehicles utilizing the center two-way left turn lane. Other accidents involving vehicles turning left from an access across the roadway, rear end collisions resulting from vehicles trying to merge into the left turn lane, and many other related accidents are not included in the previously noted accident data. Because of this, it is reasonable to assume that many additional accidents could have likely been prevented had the raised median been installed. High Driveway Density: 55 accesses per mile 40+ accesses per mile equates to 10mph reduction in free flow speed Accident Ratio: — 29 accident associated w/ left turns / 76 total accidents = 38%