WASHINGTON —Congress is expected to approve the reauthorization of federal support for the Lake Pontchartrain Basin as soon as Wednesday after the U.S. Senate approved the legislation late Monday.

The Lake Pontchartrain Basin Restoration Act was successfully amended into the Federal Water Pollution Control Act by U.S. Sen. David Vitter, R-La., who first authored the Lake Pontchartrain legislation and had it passed into law as a freshman congressman in 2001.

“Since passing the Lake Pontchartrain Basin Restoration Act in 2001, we’ve accomplished a lot — including improvements in water clarity and the return of pelicans, oysters and blue crabs to the lake,” Vitter said in the announcement. “But the work isn’t done, and my legislation allows us to continue to restore one of our nation’s estuary treasures and help the local communities address water infrastructure problems.”

The five-year reauthorization maintains the partnership between local stakeholders and the U.S. Environmental Protection Agency. The legislation, which was co-sponsored by Sen. Mary Landrieu, D-La., could send $20 million to Pontchartrain basin projects through 2017 and it allows the EPA to cover up to 75 percent of projects costs.

“When I was a kid, Lake Pontchartrain had unfortunately come into a really sad state,” Vitter said Tuesday on the Senate floor. “It was visibly dirty. No one would think to swim there.”

But the Lake Pontchartrain Basin Foundation rose up as a “grassroots citizens’ effort” and turned things around, Vitter said, and the federal support for that ground-up effort is instrumental.

Vitter, who becomes the ranking Republican member of the U.S. Senate Environment and Public Works Committee in January, had the amendment added in by the U.S. Sen. Barbara Boxer-led committee in June.

The full Senate approved it by unanimous consent on Monday without requiring a roll-call vote.

The legislation is designed to protect Lake Pontchartrain and surrounding areas through restoration and cleanup efforts. The act gives the lake federal protection status closer to the Great Lakes and the Florida Everglades.

Carlton Dufrechou, of the Pontchartrain Restoration Program Executive Committee, said the restoration program has been critical to improving the basin’s “environmental health.”

“It’s been the catalyst for over 100 projects that have reduced pollution from sewerage plants, dairy operations and helped preserve Louisiana’s fragile coast,” Dufrechou said, “and the results are quantifiable. Lake Pontchartrain is again fishable and swimmable.”

“That’s the ultimate measure — when citizens can actually go and swim in the lake,” Vitter said, after noting Dufrechou’s remarks.

Although not technically a true lake, the 630-square-mile Lake Pontchartrain is one of the largest estuaries in the nation and it is surrounded by more than 1.5 million residents, making it the most-populated area in the state. The basin region is made up of 16 parishes in the New Orleans, north shore, River Parishes and Baton Rouge areas.