DAVID GREENE, HOST:
Imagine being on a quiet fishing trip and suddenly coming face-to-face with creatures who are huge and can leap out of the water. And, by the way, they reproduce in big numbers. They are Asian carp. They have already invaded parts of the Mississippi River and its tributaries. Now there are fears Asian carp could take over the Great Lakes. Researchers believe they know how to slow this invasion but it could be costly and it could take decades.
Here's NPR's David Schaper.
(SOUNDBITE OF A MOTOR BOAT)
DAVID SCHAPER, BYLINE: For years, environmentalists, conservation groups and others in the Great Lake region have been sounding the alarm, warning of a pending invasion of an aquatic kind.
UNIDENTIFIED MAN #1: Ooh-ha.
UNIDENTIFIED MAN #2: We've got two.
UNIDENTIFIED MAN #1: Crap. Crap.
UNIDENTIFIED MAN #2: Got three.
UNIDENTIFIED MAN #1: Oh, crap, they hurt.
SCHAPER: This is YouTube video of two men boating up the Wabash River in Indiana, laughing as they dodge dozens of huge, flying, Silver Asian carp - an invasive species of fish that leaps out of the water when disturbed by motors. With its cousin, the Bighead Asian carp, these invasive fish have completely taken over parts of the Wabash, as well as portions of the Ohio, the Illinois, and other rivers in the Mississippi River watershed.
They're not just big, but Asian carp are prolific reproducers and voracious eaters, without natural predators. So they can quickly crowd out native species of fish. Many scientists fear if the invasive species becomes established in the Great Lakes, it could devastate commercial and sport fisheries worth billions. So many Great Lakes advocates have been calling for the U.S. Army Corps of Engineers to seal off the rivers and man-made canals in the Chicago area that Asian carp could travel through to get into Lake Michigan. The Corps has spent the last few years studying just how to do that.
DAVE WETHINGTON: Thank you, Eddie. And good afternoon everyone...
SCHAPER: Dave Wethington is Corps' project manager for the study. In a conference call with reporters, he detailed eight options to block the advance of Asian carp. Two of them would involve constructing barriers in Chicago area waterways, in order to physically separate the Great Lakes and Mississippi River watersheds.
WETHINGTON: Physical separation does have the ability to really buy down the risk of all types of aquatic nuisance species transfer through that aquatic pathway.
SCHAPER: There's a catch or two. Depending on where the barriers go, physical separation would cost at least 15-and-a-half billion dollars. And because the barriers would require the construction of new flood controls in the Chicago area, including storm water tunnels and reservoirs, as well as water treatment plants, Wethington says the project could take at least 25 years.
WETHINGTON: Is that going to be in time? You know, your guess is probably as good as anybody else's.
SCHAPER: With the Asian carp at the Great Lakes' doorstep that answer is not sitting well with Michigan Republican Congressman Dave Camp.
REPRESENTATIVE DAVE CAMP: We're looking for a developed proposal that would bring about immediate action to eliminate this threat. And obviously 25 years doesn't fit that matrix.
SCHAPER: Camp and Michigan Democratic Senator Debbie Stabenow pushed through legislation accelerating the Army Corps study by two years, and hoped it would only focus on separating the watersheds.
But the Corps is presenting other options, too. For example, a new kind of lock-and-dam system that would flush and treat water in the locks to eliminate invasive species. But most of the plans would still cost billions and take at least 10 years to implement. The Army Corps of Engineers is holding a series of public hearings on the proposals beginning Thursday in Chicago.
David Schaper, NPR News, Chicago.
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