Approaching the new bridge from the south. Here there are two travel lanes, bike lanes and parking lanes.

When new bridges are built in Chicago, the Illinois Department of Transportation (IDOT) generally requires that they be built to accommodate projected traffic demands. The assumption is that in the future there will be more people driving than ever before, although most of us hope this won’t be the case.

So when the Chicago Department of Transportation (CDOT) rebuilt the North Damen Avenue bridge over the Chicago River in 2002, IDOT insisted that the old two-lane bridge be replaced with a four-lane, although Damen is generally only a two-lane street. But as a rule, if you give Chicago drivers the opportunity to speed, they will.

So it shouldn’t have been a surprise that as soon as the new bridge opened, motorists took advantage of the new half mile of wide open space between stoplights at Fullerton and Diversey to put the pedal to the metal. The speeding cars, plus the fact that bike lanes weren’t included in the project, turned a formerly bikeable bridge on a recommended bike route into a hostile environment for cyclists.

Fortunately CDOT soon recognized the problem and in 2004 it retrofitted the bridge with a road diet. In this four-to-two conversion, the extra travel lanes were taken out and replaced with bike lanes and painted medians. This calmed traffic and provided dedicated space for cycles, making the bridge bikeable once again. This was one of Chicago’s first road diets, and it was a very progressive move at the time.

The bike-friendly Damen bridge, after the road diet. Photo by Serge Lubomudrov.

Nowadays road diets are common here. For example, Kinze Street underwent a four-to-two conversion last year to accommodate the city’s first protected bike lane, and CDOT’s plan to install 150 miles of protected and buffered bike lanes by 2015 will likely involve dozens more road diets.

However, the new “tied arch” bridge on the 1100 block of North Halsted Avenue, near Divison Street, seems to be another example of the Illinois transportation department having its way, a “road binge” if you will, to the detriment of Chicago cyclists. CDOT recently completed this $13.7 million project, funded by the Federal Highway Administration, along with rehabbing the bascule bridge on Halsted just north of Chicago Avenue, 800 North, paid for with local Tax Increment Financing money.

As you continue towards the new bridge from the south, the bike lane becomes dashed, permitting cars to cross into the right-turn lane which has replaced the parking lane.

There’s a lot to like about the tied-arch bridge. Unlike Tribune architecture critic Blair Kamin, I think this bow-shaped span, painted a cheerful cobalt blue, is a beautiful addition to our skyline. The old metal-grate decking has been replaced by a solid concrete surface that’s much safer to bike on. The rehab to the bascule bridge near Chicago Avenue also included adding bike-friendly concrete infill on the sides.

Both bridges include bike lanes plus wider sidewalks with guardrails to protect pedestrians from cars. These accommodations seem to reflect CDOT’s recent trend towards creating facilities that serve all road users, not just drivers, which has blossomed under forward-thinking Commissioner Gabe Klein.

Klein speaks at the press confrence to mark the reopening of the bridges. 27th Ward Alderman Walter Burnett is to his left; Deputy Commissioner Dan Burke is wearing the safety vest.

On the other hand, it seems IDOT mandated that the new tied-arch bridge be expanded from two to four lanes. So, despite the bike improvements, I feel the net result is a bridge that’s less comfortable to bike on than it was before. I’ve ridden over the new bridge on several different occasions and it’s clear to me that drivers are using the extra lanes as an opportunity to speed.

Also, to accommodate right- and left-turn lanes at the Halsted/Division intersection, the northbound bike lane over the tied-arch bridge is sandwiched between travel lanes. As we’ve written before, cycling between two lanes of moving cars, trucks and buses is not a relaxing feeling. Bottom line: as a two-lane, this would have been a very bikeable bridge, but as a four-lane it’s a structure that seems likely to intimidate inexperienced cyclists. It seems like a missed opportunity.

This seems like a scary situation for newbie cyclists.

If CDOT eventually finds that speeding is an issue on the tied-arch bridge, maybe it will eventually retrofit the bridge with a Damen Avenue-style four-to-two conversion. The roadway width would allow the agency to include two travel lanes, a left-turn lane and protected bike lanes, which would be a huge improvement over the current situation.

But last week after a press conference to mark the reopening of the bridges, I spoke with CDOT Deputy Commissioner Dan Burke, who oversaw the project, and he didn’t seem to think the new design encourages speeding. Burke wasn’t aware of the Damen Avenue Bridge road diet, so after telling him that story I asked for more info about the tied-arch bridge:

Can you tell me why this bridge was converted from a two-lane to a four lane when the rest of Halsted is generally a two-lane?

Well, the new bridge accommodates all users. We have eight-foot-wide sidewalks, we have bike lanes and we also have capacity for motorized vehicles to move through the corridor as well. We took a balanced approach to all the users of this corridor and I think we’ve been able to provide a solution for everyone.

What was the reasoning behind putting four travel lanes on the bridge when the rest of Halsted is two lanes?

If you look at the traffic study, at the volumes of traffic that come through here, the right-turn movements, the left turn movements, at the time it was found it was warranted. And we were able to keep vehicles moving through here and also incorporate a bike lane, so it was a win-win for everyone.

Approaching the Division Street intersection from the south.

Would there have been problems if there had only been two travel lanes. Do you think that traffic would have backed up?

The intersection at Division is a very high-volume intersection. So what we were able to do was provide the capacity to move vehicles efficiently through there. Moving vehicles efficiently does not equate to speeding. People going faster than the speed limit is a separate and distinct issue. We’re just providing for a flow through the area.

Steven adds:

The design that exists now is not the only design that CDOT could have come up with. There are several design elements they could have used that allows for 2 travel lanes (1 in each direction) + 2 bike lanes without excluding future widening, should that be deemed necessary. To achieve the desired flow (whatever flow this design is intended to accomplish), it might not have been necessary to have the lane configuration on the bridge match the lane configuration closes to the intersection.

Was it really necessary to have a 500 feet long right turn lane on the right side of a centered bike lane? We’ve discussed here and here that centered bike lanes are not comfortable for people who bike. Chicargobike’s post today about how the Streets for Cycling Plan draft network does not meet the “8 to 80″ designation is recommended reading.

Read the discussion about this bridge on The Chainlink.