Zebra mussels halt work on St. Croix bridgeSTILLWATER, Minn. (AP) — Work on a new four-lane highway bridge over the St. Croix River connecting Minnesota and Wisconsin has been halted after dead zebra mussels were found on six construction barges headed for the waterway.
STILLWATER, Minn. (AP) — Work on a new four-lane highway bridge over the St. Croix River connecting Minnesota and Wisconsin has been halted after dead zebra mussels were found on six construction barges headed for the waterway.
Inspectors found the invasive species on the barges, trucked in from Milwaukee and the Fox River in Oshkosh, Wis., this week at the construction staging area for the new bridge, according to the Minnesota Department of Natural Resources.
The DNR was investigating the incident, according to spokesman Chris Niskanen, who added none of the barges entered the St. Croix River.
The National Park Service officials warned in March that the bridge replacement project, with a price tag of $580 million to $675 million, could potentially create a new avenue for the invasive mollusks to re-establish themselves in the river, where its population has plummeted to near zero in some areas.
The Minnesota Department of Transportation and the contractor, Ed Kraemer & Sons Inc., of Plain, Wis., agreed to a decontamination protocol for all construction barges entering the river. The company properly treated the barge hulls with 190-degree water, Niskanen said, but it failed to scrape the dead mussels from the hulls.
"It looks like they did not fully complete the decontamination process," he said.
Inspectors with Kraemer and MnDOT found the mussels on the barges at the staging area on Wednesday and called the DNR, which had trained inspectors to watch for the zebra mussels.
"The things that were put in place to catch this kind of issue worked," Kevin Gutknecht, spokesman for MnDOT, told the St. Paul Pioneer Press (http://bit.ly/157cGtT). "It's a stark reminder that we all have to be vigilant."
Even if the contaminated barges had reached the water, Niskanen said, the river would not have been at risk.
"They weren't viable," he said of the mussels.
Bob Beckel, regional manager for Kraemer, said the company is taking corrective action.
"The inspection at the other end was not 100 percent up to par, and Kraemer accepts that," Beckel said. "We are making sure that won't happen again."
It's the second delay for the bridge project in the past two months.
McCrossan Construction sued to stop the project last month after it was the apparent low bidder on approach work, but the job was given to a joint venture of Ames Construction and Lunda Construction. MnDOT said McCrossan's bid did not include enough work for minority- and woman-owned companies.
Gutknecht said the delays do not threaten the schedule of the overall project, which replaces the Stillwater Lift Bridge. Completion is targeted for fall 2016.