Untangling the infamous Crosstown Commons now underwayby Dan Olson, Minnesota Public Radio
One of Minnesota's largest and most expensive road and bridge projects is underway. Tree-cutting and other site work began for the rebuilding of the Crosstown Commons traffic interchange in south Minneapolis on Tuesday. The interchange will be open during construction, but with lots of diversions. Transportation officials say three and half years from now, when it's done, traffic will flow much more smoothly through the infamous bottleneck.
Minneapolis, Minn. — A Canadian by birth, Mike MacArthur is now a Minnesotan by at least one measure.
"The first traffic jam I got into was the Crosstown Commons when I moved up to Minnesota," he says.
Civil engineer Mike MacArthur's job the next few years could be described as Crosstown wrangler. He works for the Ames, Lunda and Schafer consortium, the construction companies that won the $288 million bid for the project.
MacArthur is in charge of making sure hundreds of laborers, subcontractors, truck drivers and all the rest are at the right place at the right time.
There are lots of big numbers that will be poured into the Crosstown rebuild. Not the least is 444,000 square yards of concrete for new pavement.
Steve Barrett, the Minnesota Department of Transportation resident engineer overseeing the project, explains what all that concrete will mean for drivers by late 2010.
"Even though the project is four miles long north and south, and about two miles east and west, when you figure a 12-foot lane, we add about 63 miles of concrete pavement," Barrett says.
Right now the Crosstown Commons mixes traffic from four directions -- east, west, north and south -- from two major roads -- Interstate 35W and Minnesota State Highway 62. About 200,000 vehicles a day vie for their spots on the six lanes of roadway. They have to merge and change lanes, always a taxing job for Minnesota drivers.
The rebuilt interchange will be 12 lanes at the widest, helping solve the congestion problems, and that means "a lot less weaving" according to Barrett.
Less weaving, Barrett says, because the new interchange won't require as many drivers to switch lanes.
"Traffic that just wants to stay on 62 and get across 35W won't have to merge in with the same traffic," he says.
Here's another Crosstown superlative. There'll be 25 new bridges, replacing the existing 21. And contractors are using a bridge-building technique new to Minnesota.
Ames, Lunda and Schafer engineer Mike MacArthur says most bridges are built in place. But segments of the Crosstown bridges will be built south of the Twin Cities and trucked in.
"Bridges ... are going to be cast out towards Coates by Lunda Construction, and they're going to be brought on site and erected on site," MacArthur says.
The rebuilt Crosstown interchange will include room for transit, and lanes for high-occupancy vehicles. MacArthur calls the three-and-a-half-year construction timeframe, and the $288 million pricetag for the project, doable.
Former MnDOT officials say the ultimate pricetag could easily exceed $288 million with change orders, because of increasing costs for cement or steel.
The officials say the traditional cost ratio for a project is 60 percent for materials and 40 percent for labor. They says profit for the builders ranges from 8 percent to 10 percent of the total cost.
At one of the construction headquarters offices, Mike MacArthur sits down in a folding chair to talk. MacArthur says he studied the detailed plans of the Crosstown project for two and half months. He meets with engineering colleagues several times a week.
The rest of the time, MacArthur says, he's on the site, smoothing out the wrinkles that occur with nearly 300 workers and dozens of subcontractors.
"You don't have materials show up on site, or you don't have a subcontractor show on site when he was supposed to, that happens all the time," MacArthur says.
The biggest construction challenge is keeping the Crosstown interchange open to traffic during construction. The only exceptions will be occasional weekend nighttime lane closings. But it won't be traffic as usual.
There'll be diversions and detours. One of the first will be for drivers using the Diamond Lake bridge that spans Interstate 35W in south Minneapolis. The bridge closes on May 29. It will be demolished and eventually replaced.
- All Things Considered, 05/15/2007, 5:20 p.m.