WASHINGTON – More than 50 years after the Upper St. Anthony Falls Lock and Dam established Minneapolis as the head of commercial navigation on the Mississippi River, momentum is building in Congress to close the lock to protect Minnesota's northern waters from invasive Asian carp.

Environmentalists and sportsmen are cheering a House panel's decision Thursday to incorporate the lock closure into legislation funding ports and water projects across the nation — the first bill of its kind in six years. Despite a budget standoff that could shut down the government in two weeks, the water resources bill is widely expected to pass with rare, bipartisan consensus.

River industry groups are fighting the lock closure, which they say will hurt the region's economy and do little to stop the northern advance of Asian carp.

A pair of gravel and scrap metal yards on the Minneapolis waterfront still use the lock, but local officials are eager to redevelop the city's industrial port, and a riverboat company has already been relocated downriver.

"It's a rather dramatic step that we have to take," said U.S. Rep. Rick Nolan, a lawmaker from northern Minnesota who has worked with Minneapolis Democrat Keith Ellison to move the lock closure through Congress. "We're not sure if this will work, but we sure feel like we have to try to do something."

The issue is rekindling the traditional rivalry between Minneapolis and St. Paul, sister cities that have fought over locks and dams for the past century. One of the first lock and dams on the Mississippi, the Meeker Island Lock and Dam near Minneapolis' Lake Street Bridge, was shut down by Congress in 1909 in favor of the hydroelectric Ford Dam a few miles downstream toward St. Paul.

Closing locks and dams is still controversial — and rare.

"I wouldn't be surprised if the Meeker Lock and Dam was the last one to be decommissioned," said Irene Jones, program coordinator for Friends of the Mississippi River, an environmental group that supports closing the St. Anthony Falls lock.

"We see it as a fairly simple and inexpensive solution, compared to what we're going to have to do downstream to stop the carp," Jones said. "It's sort of a no-brainer."

The Minnesota delegation is divided on the closure, but not along the usual party lines. The Senate already has passed a water bill backed by Democrats Amy Klobuchar and Al Franken that would decommission the lock. A majority of the Minnesotans in the House also back the idea. Three Minnesotans have kept their names off the bill: Republicans John Kline and Michele Bachmann, and Democrat Betty McCollum.

'A stop sign'

McCollum, whose district includes St. Paul, is leading a bipartisan push backed by the entire delegation that would seek a comprehensive U.S. Fish and Wildlife Service strategy to combat invasive species throughout the Mississippi and Ohio River basins. Like Kline and Bachmann, McCollum has stayed technically neutral on shutting down the St. Anthony Falls lock, saying it would do nothing to protect the St. Croix and Minnesota rivers.

McCollum aide Bill Harper said that while she is not actively opposed, she has said that closing the St. Anthony Falls lock "is like a stop sign that tells the carp to go back to St. Paul."

Proponents of closure say the effect on a handful of Minneapolis companies pales in comparison to what could happen to Minnesota's $11 billion-a-year tourism industry if Asian carp, an invasive species that crowds out native fish, begin breeding in the state's lakes and rivers.

Alarms were raised anew this summer, when the carcass of a silver carp was found at the base of a dam in Winona — the farthest north the species has been detected.

With national business and environmental groups looking on, opponents worry about the precedent set by shutting down a working waterway over unwelcome fish. Legal battles already have been fought over efforts to close Chicago-area shipping locks to keep carp out of the Great Lakes.

In an effort to blunt industry opposition, the pending federal legislation would trigger the Minneapolis lock closure on the basis of its limited use, not the threat of carp.

"They're looking at it more as an economic issue," said Marc Smith of the National Wildlife Federation, part of a coalition trying to stop the spread of carp. "There's no precedent for closing a lock for an invasive species."

'Chain on the dog'

That does little to diminish the concerns of Al Christopherson, a southern Minnesota farmer who leads the Upper Mississippi Waterway Association, which represents barge companies and other industrial users.

"You know the old saying: Once you get the chain on the dog, then after that the only difference is the length of the chain," he said.

Christopherson says closing the lock would cut wages and economic output by more than $40 million. A Metropolitan Council report last year said closing the lock would wipe out 72 jobs.

The Minnesota Department of Natural Resources supports the closing, but some federal officials say the danger to northern Minnesota is being exaggerated.

Judy DesHarnais, of the St. Paul district of the U.S. Army Corps of Engineers, which oversees the locks system, notes that, in addition to other dams upstream of the Twin Cities, the Boundary Waters Canoe Area Wilderness and other popular northern Minnesota waters are not connected to the Upper Mississippi River watershed.

Either way, with Thursday's unanimous vote in the House Transportation and Infrastructure Committee, the days of the St. Anthony Falls lock appear numbered. However, both sides agree even that measure will not end the threat from carp, zebra mussels and other invasive species.

"My God," Nolan said after the vote, "there are at least 100 other invasive species that are all moving our way."

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