Many of us love Madison for its beautiful lakes, but a new study shows they might face a bleak future.

The UW-Madison study shows it could take a thousand years for Lake Mendota to recover from the effects of phosphorus run-off.

Phosphorus from fertilizer used on farms and lawns washes into our lakes, causing algae to grow, depleting oxygen in the water, and killing fish.

The UW study shows phosphorus build-up in Lake Mendota watershed could cause serious environmental problems for hundreds of years, if action is not taken.

The Sierra Club says there are some things you can do now to help protect our lakes. "The best thing you can do is keep your lawn and soil on the land and out of the lake. Plant a rain garden, use phosphorus-free fertilizer, and fund county efforts that will help restore the watershed to help farmers conserve the land too," says Brett Hulsey from the Sierra Club

Hulsey says restoring wetlands around the lake would also help because they act like filters. Taking steps to control manure run-off would also make a big difference.

Hulsey adds the state just cut its portion of the funding for a Lake Mendota watershed plan.