Traffic travels in both directions. So it makes sense we’d have a malicious moniker for two-way left turn lanes (TWLTLs). Are they actually dangerous, though? Let’s look at the safety of these middle lanes. After all, they are on roads pretty much everywhere in the United States.

Sources cited:
Mukherjee, D. Choosing Between a Median and a TWLTL. ITE Journal, 1993, pp. 25–30.

Ballard, J. Computer Simulation Study of the Operational Effects of Two-Way Left-Turn Lanes on Urban Four-Lane Roadways. Transportation Research Record, 1988, pp.1-10.

A Policy on Geometric Design of Highways and Streets, AASHTO, Washington, pp. 9–182-9–183.

Additional reading:
Tabin, S. Truck Involved in Crash That Killed a BYU Student Belonged to Deputy, Sheriff’s Office Says. The Salt Lake Tribune, Mar 18, 2021.

Road Guy Rob

Rob is a 12-year veteran public radio reporter and talk show producer. Other staffers at the station called him the "road guy" because he kept running off to cover all the transportation stories. Rob has degrees in Geography (BS, 2010) and Civil Engineering (MS, 2018).

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