Just as a landmark report has documented a dramatically healthier upper Mississippi River, congressional inaction on Asian carp is threatening to undermine this progress, jeopardizing not only the Mississippi but the well-being of the beloved lakes and rivers in its vast Minnesota watershed.

Invasive Asian carp, a family of four pugnacious-looking fish, have consistently migrated up the Mississippi faster than policymakers have moved to stop them. Halting their progress in Minnesota is especially important, according to the new report from the National Park Service and Friends of the Mississippi River advocacy group. While the report concluded that the river is recovering from decades of neglect -- the result of the federal Clean Water Act and concerted public policy -- the piscine invasion remains a critical concern.

The carp species' voracious appetite leaves little for native fish to eat. The silver carp's mind-boggling leaping ability poses danger to boaters. This one-two carp combo could wreak havoc on Minnesota's $11.3-billion-a-year tourism industry.

While Asian carp have been pulled out of the St. Croix River near Prescott, Wis., and out of the Mississippi near Winona, there may still be time to prevent the species from establishing large populations. The strongest possible action is needed to protect Minnesota waters, especially the lakes and rivers that feed into the Mississippi north of the Twin Cities.

Minnesota legislators and Gov. Mark Dayton deserve credit for moving aggressively at the state level to combat the carp. But congressional action is needed to take the strongest step possible to deter the invasion: closing the Upper St. Anthony lock near the Stone Arch Bridge in Minneapolis.

The falls there have long been a natural, physical barrier to aquatic life moving upstream. But the lock's use likely allows carp to hitchhike in the water that moves recreational boaters and limited barge traffic from one segment of the river to another. Closing the lock would inconvenience some businesses, but this needs to be weighed against the 239,000 state jobs dependent on tourism.

There was reason earlier this year to be optimistic that Congress would move with uncharacteristic speed to take this critical step. In March, several conservation-minded members of the state's Washington delegation publicly announced legislation that would study the lock's temporary closure and mandate its closing if adult Asian carp were found downstream above Hastings or juvenile carp above Alma, Wis.

Minnesota Democratic Rep. Keith Ellison is the bill's chief author in the U.S. House, with Republican Rep. Erik Paulsen and Democratic Rep. Tim Walz serving as cosponsors. Democratic Sen. Amy Klobuchar is carrying the bill in the U.S. Senate, with Sen. Al Franken cosponsoring it.

It's unclear why the other members of the Minnesota House delegation haven't signed on. It's hard to think of a bill that's more "pro-jobs" in this election year or one that would do more to protect the state's cherished water resources.

Unfortunately, the proposed Upper Mississippi Conservation and River Protection Act of 2012 has not made needed progress. Months after its introduction, it remains bogged down in committee. "I am not willing to accept an outrageous lack of action from Congress,'' said Minneapolis Mayor R.T. Rybak last week.

Nor should any other Minnesotan accept this congressional foot-dragging. Closing the lock isn't a panacea, but it's the most effective weapon available against this aquatic invader. Minnesota can't afford to wait to use it.


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