FORT WAYNE, Ind. — Environmental officials are celebrating the completion of a nearly 2-mile-long, 80-foot-wide earthen berm designed to keep Asian carp from reaching the Great Lakes.

The $4.4 million project at the Eagle Marsh Nature Preserve in Fort Wayne is designed to block floodwaters and prevent carp from crossing from the Wabash River watershed into the Maumee River watershed, which empties into Lake Erie at Toledo, Ohio. The nature preserve drains into both watersheds.

“This is a great example of how a smaller investment up front can save a whole lot of money and heartache after the fact, after damage could have been created,” Cameron Davis, who coordinates Great Lakes policy for the U.S. Environmental Protection Agency said.

Eagle Marsh is considered the second-most important spot, after the Chicago Area Waterway System, for stopping the voracious invasive species from reaching the Great Lakes. Scientists say Asian carp could disrupt food chains and out-compete native fish.

The berm, which is 1.7 miles long and averages 7½ feet high, has been planned since 2014 and construction work began last fall.

“We don’t want to ever get to that point, where the fish are right there at the gate.