Diamond Lake's ship has come in, thanks to an unusual neighborhood endeavor to clean up the small south Minneapolis lake's dirty water.

With a $224,224 grant from the Minnesota Clean Water fund, residents will receive financial help to make changes in their yards that will help the lake. Money for such projects has been made available for the first time this year through the Minnesota Legacy Amendment, which was approved by voters in 2008.

Mary Martini, a Diamond Lake homeowner since 1979, said Friends of Diamond Lake started three years ago to find a way to clean up the lake, which has the lowest possible water-quality grade. The grant is a break-through, she said.

"People need a little bit of a nudge," she said.

The money has not yet been divided precisely, but about $100,000 will be used for 50-50 matches for 50 residents to build rain gardens, trickle-through porous driveways or underground rainwater storage and watering systems.

About $100,000 will go toward similar but larger projects at nearby Diamond Lake Lutheran Church and Pearl Park. Some will also be spent on design, administration and inspection of the work, said Julie Westerlund, communications manager for Minnehaha Creek Watershed District.

The Watershed District, which is administering the grant, will approve each project and inspect its completion before reimbursing residents for their work, Westerlund said.

Runoff has degraded Diamond Lake over the years and has lowered its Watershed District water quality grade to "F." Dirty water is "coming from streets and driveways and sidewalks and whatever that water is carrying ends up in the lake," said Tim Brown, environmental operations manager for the Minneapolis Park Board.

At Martini's house, two roof downspouts send water "right down our driveway and into the storm sewer and right into Diamond Lake," she said.

She and her husband, Stuart Goldstein, a professor of biology at the University of Minnesota, plan to tear up their front yard and redirect the downspouts to a rain garden. "All that water will percolate down through the ground. It's as though our whole property were a natural system that allows the water to percolate down through," she said.

The Friends of Diamond Lake organized the neighborhood for the project. The group began by forming a lake association with help from the Watershed District. Next residents sought training on how to write a lake management plan.

After the Minneapolis Park Board approved the plan, Hedberg Landscape and Masonry Supplies announced that it wanted to work with a neighborhood on a green community makeover. Hedberg and the Diamond Lake group worked with the watershed district to submit the grant application.

The district made Hedberg the project manager. The company sells products that can be used in the work, but residents are not required to buy from Hedberg.

Diamond Lake Lutheran Church, which sends sheets of water to the lake from its roof and parking lot, plans to put in a big rain garden as well as an underground storage tank for rainwater that can be used for watering, Martini said.

Pearl Park, at the north end of Diamond Lake, will have some of its parking lot replaced with porous pavement to allow the rain to trickle through. Underground rainwater storage will be built there, too.

The work is expected to be finished by July.

Laurie Blake • 612-673-1711