Road Diets

Note: This article appeared originally in the Missoula Downtown Association Newsletter in 2005.  Mr. King has since retired, after helping Missoula become a more walkable community. While his letter addresses Broadway, the concept of 4-lane to 3-lane conversions (or ‘road diet’) is applicable for sections of Higgins, Russell, Stephens and 4-lane streets everywhere. Let us know if you want help making your streets safer and more enjoyable for all!

Road Diet for Broadway Considered
by Steve King, Missoula City Engineer

Communities throughout the country are looking at converting their old four-lane downtown highways into new three-lane urban roadways. There are a number of very important reasons to consider a Broadway “Road Diet” as it is often called including enhanced business access, safety, and increased downtown vitality.

At first glance, it would seem obvious that removing travel lanes from Broadway would create congestion with a loss of capacity for moving cars through Missoula. But what we see downtown is the inside lane of the four-lane street being used as a left turn lane thereby limiting it’s use as a through lane. The curb lane handles most of the through traffic because the street has no left turn lane. Therefore, a three-lane street with a left turn lane handles about the same volume of traffic as a four-lane street. A three-lane design could enhance the ability to make left turns at both street intersections and business driveways.

A three-lane street is generally safer than a four-lane road, resulting in a reduction in the rate of accidents. This is due in part due to reduced speeds, reduced variation in lane speeds, and less speeding. Conflict points for drivers are reduced and the “sight distance” for intersection turning movements is increased. A Broadway road diet would allow space for new bicycle lanes through downtown. A three-lane street reduces the crossing distance where pedestrians are exposed to moving traffic, and can create a refuge island where a pedestrian can wait for a gap in traffic to complete their crossing.

One of the side affects of a downtown road diet is enhanced business vitality. Better pedestrian and bicycle accessibility, along with a safer street for drivers can add up to a more vibrant downtown Missoula.

For the reasons mentioned above the City Public Works Department is working with the Montana Department of Transportation to consider converting Broadway to a three-lane from Madison Street to the California/Toole Street intersection. The Missoula Downtown Association, along with the Parking Commission and Missoula Redevelopment Agency are key constituents for this project. If you are interested in commenting please contact the Missoula City Engineer, Steve King, at 523-4620.