A rain garden constructed by Black Hawk Lake Watershed Project leaders at Lake View City Hall helps decrease the level of phosphorus getting into the lake. Urban residents are encouraged to purchase rain barrels and to construct their own rain gardens in the effort to help with the Black Hawk Watershed project.
A rain garden constructed by Black Hawk Lake Watershed Project leaders at Lake View City Hall helps decrease the level of phosphorus getting into the lake. Urban residents are encouraged to purchase rain barrels and to construct their own rain gardens in the effort to help with the Black Hawk Watershed project.
Wednesday, July 11, 2012

About 400 tons of soil and 866 pounds of phosphorus have been kept from Black Hawk Lake in a six-month effort to block farmland runoff from the lake.

State and local officials held their fourth information meeting on the watershed-improvement project Saturday in Lake View but billed it as a bigger kickoff event. About 100 residents attended.

The Black Hawk Lake watershed is a 13,156-acre area that drains via Carnarvon Creek to the lake and is located in both Sac and Carroll Counties. Three-fourths of that area is farmland.

The lake is fairly shallow with an average depth of only 7 feet, which can heat quickly and spur algae growth fed by the phosphorus. Further, soil clouds the water.

Lake View City Manager Scott Peterson said about $444,000 worth of state and federal funds have been spent to put soil-conservation practices — such as no-till farming — in place on about 2,550 acres of the watershed.

“This (is) a large-scale-improvement project to help enhance the quality of the lake,” Peterson said.

At stake is one of the biggest economic engines of the area — the lake averaged about 146,000 annual visitors between 2002 and 2005, according to Iowa State University estimates. Those visitors spent about $19 million each of those years, which supported 379 jobs in the area.

The lake might be dredged in several years, Peterson said, but the first task is to cut the amount of soil and phosphorus that flows to the lake.

“Dredging may happen at some time, but there is a lot of work that needs to be done prior to that,” Peterson said, and added that dredging would deepen the lake.

T.J. Lynn, who heads the water-quality project, believed the Saturday event went pretty well, which is encouraging to state officials and keeps the funding for the project coming.

“With Black Hawk there seems to be a lot of pride with the lake and the area,” Lynn said. “The people want to work with us to try and help the lake out. There’s a lot of ownership in it.”

City folk can help, too, by purchasing a rain barrel to hold rainwater to use for gardens and flowers or to have a rain garden — little constructed areas designed to capture rain to help with the watershed project.

Farmers have also been really supportive of the idea, Lynn said.

“We have had some really good people jump on board, and we have conservation on the ground,” he said.

The money that is funding the project has helped with constructing the rain gardens at City Hall and private homes. The majority of the funds has been put towards the agricultural land in the watershed including conservation practices such as strip-till, no-till, cover crops such as oats, rye grass or winter wheat, and stream-bank-erosion issues.

“Hopefully the farmers are getting the most bang for their buck while helping out Black Hawk Lake,” Lynn said. “Seventy-five percent of the water shed is in agriculture row-crop production, so throughout the project that is where most of the funds will go toward.”

Iowa Secretary of Agriculture Bill Northey, Natural Resources Conservation Service assistant Jon Hubbert and Department of Natural Resources director Chuck Gipp attended Saturday’s meeting.