Building a 2,100 foot bridge while it carries 80,000 vehicles a day

Drivers tend to complain about highway construction but it can be quite complex, particularly when a long span and lots of cars are involved:

Bridges are particularly challenging because they require intricate, and potentially dangerous, work to be done while cars whiz past below, officials said.

Think about those girders, for instance. Work crews use two cranes to lift each girder into the air and then lower it onto the frame of the bridge. The cranes don’t release the girder until it has been bolted into place, officials said.

After the girders are in place, protective plywood shielding is installed between them. The shielding supports workers as they pour the concrete “floor” of the bridge.

The whole process requires only short, intermittent lane closures, Lafleur said.

“We do most of the work overnight to keep traffic interruption at a minimum,” she said. “But of course, night work presents its own challenges, with lighting and visibility especially.”

The average driver won’t even think about any of this when making their way over the bridge. But, if the predictions in the article are correct, they will enjoy the 35% reduction in travel time through the area.

Summarizing the sides for and against the Illiana Expressway

The Daily Herald does a nice job laying out the opposing positions regarding the Illiana Expressway. There seems to be a little bit of everything needed for a really contentious development debate:

1. Lots of money is at stake for building the highway.

2. Thousands of jobs for construction and in projected economic development. Perhaps more importantly, who gets to take credit for the jobs? Next, would these jobs take away from potential jobs elsewhere?

3. Questions about whether the highway is really needed to ease truck traffic.

4. Whether the highway will serve an area ripe for suburban development (southern Will County) or whether this is primarily about shipping freight.

5. Politicians from elsewhere in the Chicago region differ on whether the road is good for the region. Additionally, some argue the highway projects they support are more important and deserve the money.

6. Is there enough money behind this public-private partnership so that state taxpayers aren’t left on the hook?

All of this reminds me that building highways was probably a lot simpler fifty years ago. For those who want more highways today, it is too bad they didn’t have the foresight to construct them back in earlier eras of the interstate system.

Elgin-O’Hare highway project to take 12 years to complete

I saw the news that the Elgin-O’Hare highway extension just received the final approval from the federal government. But, one piece of information in the story stunned me:

The action, which was expected, allows the Illinois Tollway to proceed with the $3.6 billion project, which will take an estimated 12 years to complete.

Twelve years? Chicagoans are used to a lot of construction but this seems like a really long time. Here is a brief schedule according to the Elgin O’Hare West Bypass FAQ page:

Construction of the Elgin O’Hare West Bypass project could be initiated by the Illinois Tollway as soon as 2013, and would extend through 2025. While the staging plan will be refined as the Tollway advances project design, the general sequencing described in the Tollway’s Move Illinois Program includes: widening of the existing Elgin-O’Hare expressway and upgrading the I-90/Elmhurst interchange to full access, followed by the extension of the Elgin O’Hare Expressway. When the Elgin O’Hare construction is complete construction would begin on the south leg of the west bypass, with the final piece being the north leg of the west bypass. The phasing of the improvements is intended to provide the most benefit to the public as early as possible while complementing other Tollway improvements on adjacent facilities such as I-90 and I-294.

In fact, this might be the best argument I have heard for constructing highways earlier rather than latter. In addition to costs which continue to grow over time, it can often be quicker to build when there is less development.

Fuel efficiency = bankrupt highways?

Brian hit the issue almost a year ago, but Jordan Weissmann at the Atlantic recently re-focused attention on the problem of funding U.S. highways with fuel taxes:

Since back in the Eisenhower era, the federal government has maintained a Highway Trust Fund, paid for mostly by taxes on fuel, that helps cover the repair and construction of our country’s roads, bridges, and mass transit. The idea was that drivers themselves should bear some of the cost the roads they used. Unfortunately, Congress hasn’t raised the gas tax since 1993. Since then, inflation has eaten away at least a third of its value…[and] two new challenges [have] emerged. First, Americans started caring about the fuel efficiency again, as skyrocketing oil prices ended the era of gas-guzzling SUVs. Then the recession struck, and penny-pinching drivers logged fewer miles to save on gas.

The upshot, of course, is that

less money is flowing into the Highway Trust Fund, which is now facing potential insolvency in 2013, according to the Congressional Budget Office.

I guess it’s good that fuel efficiency gains are having an impact?  (Ah, unintended consequences.)  Looks like we’re headed into a world where cars will have to start paying by the mile–or the highways are going to get a lot worse.

A new bridge just beyond Hoover Dam

The road from Phoenix to Las Vegas crosses right over the top of Hoover Dam, one of the engineering marvels of the United States. Now travelers have a bypass route: a new bridge, the second tallest in the United States, was recently completed allowing travelers to avoid the slow, two-lane road over the dam.

Read more about the project at its official page.

Will the new bridge include guides who will tell you “take all the Dam photos you want!”?

The diverging diamond interchange

American interchanges can take many forms – see this field guide to highway interchanges from The Infrastructurist – including one called “the diverging diamond.” The goal is to provide better traffic flow from a road onto a highway through switching the lanes of traffic through the interchange area. That is, traffic entering on the right side of the road are then driving on the left through the interchange and vice versa.

Illinois Department of Transportation officials are considering this design, primarily being touted by Missouri officials, for an interchange in Naperville. See the design here and the background to the interchange here.