TRAVERSE CITY, Michigan — Members of Congress proposed legislation Thursday calling for additional obstacles to prevent Asian carp from reaching Lake Michigan through an Illinois waterway and a renewed push toward a permanent strategy for shielding the Great Lakes from the destructive fish.
The bill's immediate focus is the Brandon Road Lock and Dam on the Des Plaines River in Joliet, Illinois, a choke point between the Mississippi River and Great Lakes watersheds about 40 miles southwest of Chicago. The measure authorizes the U.S. Army Corps of Engineers to devise a list of technologies and devices that quickly could be installed there to block the carp's path.
Bighead and silver carp, both native to Asia, have migrated from the Mississippi up the Illinois River to the Des Plaines. The main population front of adult carp is about 15 miles downstream from the Brandon Road structures. But Rep. Candice Miller, a Michigan Republican and one of the bill's sponsors, said Illinois officials disclosed this week that nearly 30 of the invasive carp had been spotted near the lock and dam.
Scientists say if Asian carp become established in the Great Lakes, the aggressive invaders could destabilize food webs and out-compete popular native species such as trout and whitefish that support a $7 billion sport fishing industry.
"We want to do the things we can do the fastest and in the most cost-effective way that will do the most to help the situation," said Sen. Debbie Stabenow, a Michigan Democrat and another sponsor.
The Army Corps last year released eight options for halting the Asian carp's advance through a Chicago-area network of rivers and canals. The most expensive included physical separation of the two watersheds with dams or other structures, which would take about 25 years to complete and cost up to $18 million.
The report identified the Brandon Road Lock and Dam as the only spot where aquatic invaders could be stopped from entering the Chicago waterway system. Three of the options included placing electric fish barriers or a new type of lock there. Other tools might include carbon dioxide bubble screens or underwater noise cannons to drive the carp away.
The Corps is planning a study of what measures might work best at Brandon Road, spokesman Ron Fournier said. Before it can begin, officials must determine its scope, time frame and cost.
"We'd have to consider how any proposals would impact the economy and the environment, and whether they'd even be feasible," Fournier said.
The bill also would order the Corps to settle on a long-term strategy for preventing species migrations between the Mississippi and Great Lakes systems. Since releasing its report in early 2014, the Corps has waited for Congress to choose from among the options. But the legislation would give the Corps that responsibility.
The legislation drew praise from the Great Lakes Commission, an agency representing the region's eight states and two Canadian provinces, and a separate organization that promotes its fishing industry. A coalition of environmental groups also endorsed it.
Many of those groups contend physical separation is the only sure way to protect the lakes, as Miller proposed in a bill last year. But she said it was opposed so fiercely that no hearing was scheduled.
"I just don't think it's going to fly," Miller said, although Stabenow said she hadn't given up on the idea.
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