Road Diet Informational Guide

This online engineering PDH course provides information on the design and post-implementation evaluation of Road Diets, and presents the decision-making process that helps practitioners determine whether Road Diets are a good fit for a certain corridor.

 

Four-lane undivided highways have a history of relatively high crash rates as traffic volumes increase and as the inside lane is shared by higher speed through traffic and left-turning vehicles. One option for addressing this safety concern is a “Road Diet.” A Road Diet involves converting an existing four-lane undivided roadway segment to a three-lane segment consisting of two through lanes and a center two-way left-turn lane (TWLTL). The reduction of lanes allows the roadway cross section to be reallocated for other uses such as bike lanes, pedestrian refuge islands, transit stops, or parking.

 

A Road Diet improves safety by including a protected left-turn lane for mid-block left-turning motorists, reducing crossing distance for pedestrians, and reducing travel speeds that decrease crash severity. Additionally, the Road Diet provides an opportunity to allocate excess roadway width to other purposes, including bicycle lanes, on-street parking, or transit stops.

 

This 4 PDH online course is applicable to transportation engineers who are interested in improving safety and reducing highway fatalities through the use of proven safety countermeasures including Road Diets.