The Town of Brookhaven had to halt a project to drain and dredge Lower Yaphank Lake because of environmental concerns, especially for Long Island's native trout population.

Marine biologist Kevin McCallister, of Defend H20, says the project left the brook trout population in a bad way. He says it's a rare species whose population is supported in very few rivers, including Carmans River.

Brookhaven's $2.5 million project to drain and dredge the dammed-up section of the river was designed to rid the waterway of invasive plants. But the town says on the other side of the spillway, more than 300 cubic yards of sediment that was dumped into Carmans River will interfere with trout spawning season downstream. Environmentalists say the muck will suffocate trout eggs.

The town agrees, saying in a statement: "We have temporarily paused action to ensure that the Carmans River is not adversely affected by any mud from the lake bottom."

But McAllister says not only are the trout in trouble, the entire drain and dredge project is misguided.

"This is a river," he says. "Lets put it back to being a river."

The project was initially expected to be completed by spring 2019.