An Idea for Our Times: Road Diets Make Streets Safer, Save Money, Expand Road Capacity, and Promote Biking and WalkingAn Idea for Our Times: Road Diets Make Streets Safer, Save Money, Expand Road Capacity, and Promote Biking and Walking

By Jay Walljasper, guest blogger


A Peace Coffee bike delivery trailer crosses the Franklin Avenue in Minneapolis where a recent road diet created room for a new on-street bike lane.

In these lean economic times, "we need to get more use from all the streets we already have," Minneapolis Mayor R.T. Rybak told a group of leaders from Pittsburgh, Penn., and Columbus, Ohio, visiting the city to learn about successful transportation policies.

One of the best ways Minneapolis and other area cities do that is road diets-an innovative way to increase transportation capacity at little cost. "Road diets are a wonderful example of doing more with less," explains Steve Clark, Bicycling and Walking Manager for Bike Walk Twin Cities.

"What's more, road diets make streets much safer-for bikes, pedestrians, and drivers. And rarely do they reduce the capacity of streets for motor vehicles," adds Clark. He points to the Federal Highway Administration's estimate that road diets reduce crashes by up to 29 percent. That's why the agency now designates road diets as "Proven Safety Countermeasures," which they encourage traffic engineers to use.

So what exactly is this remarkable thing called a road diet? It's a simple matter of reducing the number of traffic lanes on streets with excess road capacity, and adding bike lanes, sidewalks, bus lanes, or traffic buffers to make the streets safer, more comfortable, and more efficient for other modes of transportation.

Typically, a four-lane street is reduced to three lanes with a middle lane for left turns to ensure that traffic continues to move smoothly. Three to two-lane conversions on one-way streets are also common. San Diego undertook a groundbreaking 5-2 conversion, and found that biking and walking in the area increased 1,000 percent while neighborhood noise levels dropped 77 percent, according to Dan Burden of the Walkable and Livable Communities Institute, who coined the phrase "road diet" in 1995. Significantly, speeding on the street dropped, yet motorists' travel times dropped too because stoplights were replaced with roundabouts.

Compare this roadway before and after a standard road diet. The restriping (R) creates designated space for both bicyclists and motorists while maintaining a smooth traffic flow. Photo Credit: Dan Burden

The idea of road diets is taking off around the country. Seattle and San Francisco are vying to be the nation's leader with 35 and 34 projects respectively, but Burden notes that Hartford, Conn., with less than a quarter of the population, has 17 projects completed.

Road diets are also popping up all over Minneapolis. Bike Walk Twin Cities, a program of Transit for Livable Communities, partnered with the city on a number of projects as part of a $28 million federal grant to increase bicycling and walking as transportation. Among the Minneapolis streets where road diets have recently been added in certain stretches:

*Emerson and Fremont Avenues on the North Side;

*Riverside Avenue on the West Bank;

*The Franklin Avenue bridge and 27th Avenue Southeast connecting to the University of Minnesota campus;

*Blaisdell and 1st Avenue on the South Side;

* Park and Portland on the South Side;

* Plymouth Avenue on the North Side;

* Johnson Avenue in Northeast Minneapolis.


The road diet on 10th Avenue SE in Minneapolis is an example of a standard 4-3 lane conversion.

Shaun Murphy, Minneapolis's Bicycle-Pedestrian Coordinator, expected some "bikelash" from motorists, but has heard significant complaints only about the Park and Portland project. "But we've gotten a lot compliments about it, too," he notes.

Bike Walk Twin Cities' Steve Clark notes that the road diets have been created on streets where engineers find an excess of vehicle capacity. "This is simply an efficient use of resources. Some people say we'll need that space for cars in the future, but the annual VMT [vehicle miles traveled] is going down on almost all roads in the city except freeways, while bike, walking, and transit use are going up." He notes that VMT in Minneapolis had been flat for many years, and started to decline in 2005, even before the recession hit and gas prices rose. National VMT also peaked in 2004.

Murphy says the city is pleased with results of the road diets. "Whenever we do a mill-and-overlay on a street or a sealcoat, we now look at the bike master plan and if the traffic levels are low enough-we'll look at doing a road diet."

Bike Walk Twin Cities has also worked with other communities to create other new road diets:

*Douglas Drive, from Golden Valley Road in Golden Valley to 50th Street in Crystal.

*Valley View Road in Edina between Wooddale Avenue and Highway 6.

*Portland Avenue in Richfield from 66th St. to 75th St.

*Marshall Avenue in Saint Paul, east bound, from the Lake Street Bridge to Cretin Avenue.

Steve Elkins, chair of the Metropolitan Council Transportation Committee, notes that "When a road diet is done in conjunction with a road repair project, the expense is very low-just the cost of outreach and education. You are already restriping the lines on the road."

He saw the great potential of road diets while serving on the city council in Bloomington, which did 4-3 lane conversions with bike lanes on 86th Street and 90th Street/Poplar Ridge Road, which take you nearly 6 miles from the Mall of America to Hyland Lake Park Reserve with just a four-block interruption on residential Xerxes Avenue.

"I've found a lot of research showing that at traffic volumes up to 17,500 cars a day, a three lane configuration with left-turn lanes can handle the traffic and it's much safer," Elkins says. "It makes it much more difficult for people to drive way above the speed limit weaving in and out of lanes." He adds that it also eliminates the most common crash type on four-lane streets: a left-turning motorist or bicyclist who is hit crossing in front of two lanes of on-coming traffic.

(Other studies show road diets work well at even higher traffic volumes. The Federal Highway Administration showcases a case study from San Francisco with 22,500 cars a day and a project in Orlando with 28,000 average daily trips and another in Seattle with 30,000 have been lauded by some engineers and planners.)

Elkins notes that some drivers are initially resistant to road diets, but notes that when a project is completed, "most people say they like it-it's safer and calmer and makes it easier to get around by driving."

Jay Walljasper writes and speaks frequently about how to create better communities. His website: www.JayWalljasper.com.