When DC rebuilt the 11th Street Bridge with more lanes and more highway ramps, officials insisted it would make traffic better, while many worried it would only worsen the situation by encouraging drivers to cut through DC between Maryland and Virginia. Now, residents east of the Anacostia say that the change has been a disaster for their communities.

Photo by Gary Butler on Twitter.

The 11th Street Bridge connects the Southeast Freeway, which divides Capitol Hill and the Navy Yard area and is now signed I-695, with the Anacostia neighborhood and 295. North of there, the highway along the east bank of the Anacostia is called DC-295; west, it’s I-295.

Before a massive project to rebuild the bridge over the past few years, there was no direct car connection from DC-295 to the bridge. Some drivers got off 295 at Pennsylvania Avenue and crossed the river there before getting back on the highway.

It made a certain sense to add a connection. Surely it’s logical to have ramps connecting all of the highways, right? Some drivers in neighborhoods around DC-295 found their commutes quite awkward, and the drivers getting off the highway and back on clogged up some neighborhood roads.

However, some people warned that the cure could be worse than the disease. By building a connection, it would be simpler for people already driving this route, but could also attract more drivers to make the trip, adding to traffic and pollution for people living near the highways.

I predicted in 2008 that map software would soon move away from exclusively suggesting the Beltway to circumvent DC, directing unsuspecting itinerant travelers through DC and on the 11th Street bridge. Sure enough, that started happening.

Image from Google Maps.

The Capitol Hill Restoration Society, a preservation group, commissioned their own independent traffic study of the bridge project. It predicted that traffic would increase on DC-295, the bridge, the Southeast/Southwest Freeway (695 and 395), Pennsylvania Avenue in the neighborhoods on both sides of the river, and in other places, while decreasing on the Beltway and on 295 near Bolling Air Force Base.

Drawing by the author.

At the time, DDOT officials defended the project, saying that even if it increases traffic in DC, it should move some from local streets to the highway. The project’s “Purpose and Need,” in fact, said a goal was to “reduce the volume of freeway traffic that spills onto the neighborhood streets due to current traffic patterns.”

By that yardstick, the project seems to have failed. Residents east of the river say traffic has gotten worse in their neighborhoods. Gary Butler, Justin Lini, and Marie Fritz told Martin Di Caro that more people are driving on 295, creating traffic jams, leading people to try getting off and taking local streets to get around the traffic.

DDOT might double down despite evidence of the danger

DDOT engineer Muhammed Khalid seems to feel that the solution is to keep doing even more of what his agency has already been doing. He confirmed to WAMU that traffic got worse on 295, but said all DDOT has to do is “adjust” the “deficiencies” to “minimize or mitigate” traffic problems. In other words, he wants to do even more road work to move more cars on 295.

That will almost surely only draw even more traffic to 295, making traffic worse somewhere else, and pushing people off the highway again into neighborhoods.

Khalid’s comments sound like what you hear from a lot of transportation engineers who learned one way to do things in engineering school and haven’t noticed the ways our understanding of traffic have advanced since. Traditional traffic engineering sees wider roads or more interchange ramps as the solution to any traffic problem. Unfortunately, in reality those steps only induce more traffic and make the problem worse.

If DDOT just keeps doing the same thing, the people east of the Anacostia will pay the price in worse air quality and even more traffic.