Woodrow Wilson Bridge Beats Obstacles As it Becomes Beltway Savior
|New Look. V-shaped concrete piers mimic upstream Memorial Bridges arches.|
After the huge cost run-up on Bostons "Big Dig," any $1-billion-plus transportation megaproject faces sterner scrutiny than before from the U.S. Dept. of Transportation, not to mention other federal and state auditors. What puts the Wilson bridge even more squarely at center stage is that it is Washington, D.C.s megaproject, with Congress and U.S. DOT right on its doorstep. "Were in the spotlight, so the expectations are really ramped up," says Robert D. Douglass, project director for Marylands highway agency. Click here to view drawing>>
While pleased with the progress so far, project officials know that there is lots left to do and a tight timetable. For Russell Fuhrman, executive project manager for general engineering consultant team Potomac Crossing Consultants, the overriding issue is "schedule, schedule, schedule." Fuhrman also is a senior manager with Parsons Brinckerhoff, New York City, which with San Francisco-based URS and Baltimore-based Rummel Klepper & Kahl LLP make up PCC.
The massive construction job was triggered by the need to replace the existing 44-year-old Wilson Bridge, a six-lane bascule structure. It was designed to handle 75,000 vehicles a day, but is groaning under its current 200,000-vehicle daily load. Because the bridges drawspan only has a 50-foot channel clearance, motorists also have endured about 250 openings a year so ships can pass through. A 2004 evaluation rated the old bridges condition as "fair," but, as in previous reviews, found weld metal and base metal cracks, rusting and loose or broken deck panel tie-down rods.
|Tight Quarters. Until existing bridge (right) is demolished, it restricts amount of space available for working on new northern bridge (center).|
Knowing that patchwork could not go on indefinitely and that more capacity was needed, a new crossing emerged after a long public debate. The plan now being built includes two parallel 6,075-ft-long bascule bridges, each featuring reinforced concrete piers and structural steel girders. The southern bridge will be 110 ft wide and its upstream sibling 124 ft wide. Each will have room for six lanes plus shoulders. At the peak, each deck rises about 100 ft from the top of the pier foundations. With a 135-ft clearance, annual drawspan openings should drop to 65.
The key date staring at the project team is spring 2006, when the new southern bridge is slated to open. Traffic then will be shifted to that new structure and the old bridge will be demolished. Work has proceeded on both new bridges, but once the old bridge is demolished, contractors can push single-mindedly on the second new bridge, aiming for a 2008 opening.
Keeping the project on track has not been easy. Maryland officials initially bid the superstructure as a single contract, but they were dismayed at the December 2001 bid opening when the lone bid came in at $860 million, or more than 70% above their estimate, officials were shocked. Searching for options, they recruited an outside panel, led by former Utah DOT Executive Director Thomas Warne, whose key recommendation was to split the job into three contractsone for the bascule section; a second for the mostly overland segment from the Virginia shore to the bascule; and a third piece, mostly over water, from Maryland to the drawspan.
The three-contract gamble has paid off. Maryland had more biddersthree, seven and four proposals, respectively, for the three contracts. More importantly, the three low bids came in at a combined $496 million, almost matching the states original superstructure estimate. SHAs Douglass says the rebidding "cost us a year," but saved $362 million.
Another factor behind the increased competition was that Maryland, under pressure from FHWA, dropped a union-only project labor agreement requirement. Douglass says there are contractor-negotiated union agreements on the bascule and Maryland approaches, but not the Virginia approach. Nonunion G.A. & F.C. Wagman Inc., York, Pa., won three Maryland interchange contracts, while one won by John Driggs Co., Capitol Heights, Md., was a union contract. PLAs "became a true non-issue from our standpoint," Douglass says.
In the foundation phase, another serious problem cropped up. Shock waves from driving piles were killing hundreds of fish. "Nobody had anticipated this," says Michael S. Baker, of URS, PCCs environmental construction manager. Without a fix, piledriving could have been halted for several costly months.
The remedy was air bubbles. Compressed air was fed through a perforated hose circling a pile. An outer steel tube surrounded the loop of hose. The "curtain" of air bubbles absorbed the shock waves and reduced fish fatalities to only a few. The fix was not expensive, Baker says. "This was done with stuff they had in the yard."
Steel prices were a third major threat. As steel costs soared, Maryland sought ideas from its steel fabricators, contractors and others. The outcome was a pact reached last summer for the Maryland approach and bascule under which contractors agreed to absorb increases up to 7% above steels price at the time of the bid. The state will cover increases above 7%, up to a cap of $4 million on the bascule and $9 million on the Maryland approach. Contractors also agreed to triple the penalties for missing deadlines, to $75,000 a day. A similar deal is in the works for the Virginia approach.
"Its a fair solution that the state came up with," says J. Daniel Bell, American Bridge Co. bascule project manager. Bob Dacre, vice president for project management with bascule steel fabricator PDM Bridge LLC, Eau Claire, Wis., agrees. "I think that everybody did the right thing and we reached an agreement that we consider fair and equitable," he says. Maryland officials are "very tough bargainers, but their word is good and their commitment to dealing in a fair and forthright manner is there," he adds.
Contractors on each bridge segment say their jobs are going well, but they point to challenges, some of which stem from the bridges distinctive design. Designers aimed for "something that is aesthetically pleasing, that matches the architecture of the bridges in the area," says Greg Shafer, project manager for designer Parsons, Pasadena, Calif. They had in mind crossings like the arched Memorial Bridge...