By JOHN FLESHER, AP Environmental Writer
DETROIT (AP) - Leaders of a privately funded study said Friday they're developing three alternative proposals for placing barriers between the Great Lakes and the Mississippi River watersheds in the Chicago area to prevent Asian carp and other species from slipping between them.
The study is being conducted by the Great Lakes Commission and the Great Lakes and St. Lawrence Cities Initiative, which intend to release their plan in January. They say it will provide guidance to the U.S. Army Corps of Engineers, which is doing a separate analysis of how to prevent invasive species migrations at Chicago and dozens of other locations where the two drainage basins intersect.
The Corps study is due in 2015. Critics say that's too slow, with voracious bighead and silver carp lurking near an electric barrier 37 miles from Lake Michigan. Water samples taken past the barrier have turned up DNA of Asian carp, although there's disagreement over whether the unwanted fish have gotten through. Michigan, Wisconsin, Minnesota, Pennsylvania and Ohio have filed a federal lawsuit demanding a quicker timetable.
David Ullrich, director of the Great Lakes and St. Lawrence Cities group, said their study should help the Army Corps move faster and build public support for government spending that will be required to construct the barriers.
"The hope is that people will rally around a solution to the problem," he said.
Ullrich and Tim Eder, executive director of the Great Lakes Commission, gave a preview of their plan Friday during a conference of Great Lakes scientists, activists and government officials.
They said it would offer three options for physically separating the two basins at Chicago, which were artificially linked a century ago.
One would place five barriers in rivers close to where they flow into Lake Michigan, including at a downtown navigational lock that some say should be closed to provide a barrier to the carp. Opponents say shutting down the lock would devastate cargo shipping and tour boating in Chicago.
A second option would use three barriers. The other would place one dam or similar structure near the electric barrier, which would close off all five river and canal linkups between the two watersheds in the area.
The plan will be designed with a goal of completing the separation within five years after receiving government approval and funding, Eder said.
"We need to accelerate the discussion," he said. "The Asian carp are not waiting."
Construction would take place gradually, with initial emphasis on stopping Asian carp from advancing toward Lake Michigan. Later phases would focus on stopping Great Lakes species from reaching the Mississippi basin.