Instead of completing a massive federal study that would recommend a permanent solution to the Asian carp problem by 2015, the U.S. Army Corps of Engineers will release an array of preliminary options to Congress by next year, officials announced today.

The timeline of the Great Lakes Mississippi River Interbasin Study had come under fire from some members of Congress and Great Lakes states, who criticized regulators for dragging their feet on an urgent issue.

Now, instead of unveiling a detailed proposal in about three years, the Corps will draft several alternatives by the end of 2013 and seek reaction from Congress and the public, said Jo-Ellen Darcy, Assistant Secretary of the Army for Civil Works.

"We're going to be able to get feedback on (it) before we make a final decision or recommendation so that we know that we have support," Darcy said Tuesday during a conference call with reporters.

Darcy said that the Corps does not yet know how many alternatives it will present. Although they believe the new timetable will speed up the process, there is no guarantee that Congress will take action on it any sooner than under the original plan.

"What it does is it starts the discussion earlier," Darcy said. "The ultimate decision will be made by the Congress and hopefully informed by a few of their stakeholders."

Asian carp, a voracious species of fish introduced into the U.S. from China in the 1970s, have overwhelmed native fish populations in the Mississippi and Illinois rivers on its 30-year trek toward Lake Michigan. However, the carp are just the latest in a long line of invasive species that have threatened or upset the environmental balance of the Great Lakes.

Congress initially directed the Corps in the Water Resources Act of 2007 to evaluate options and technologies available to stop invasive species like Asian carp from transferring between the Great Lakes and the Mississippi River basins.

The Obama Administration has invested more than $150 million to fight Asian carp. Ongoing efforts include electric barriers in the Chicago Area Waterways System near Lockport.

But some environmental groups have long argued that such measures are costly and may ultimately be flawed and ineffective.

Last week the electric barrier system experienced a 13-minute power outage, though officials hastened to point out that there is currently no evidence of Asian carp nearby.

cdizikes@tribune.com