Four rivers in Minnesota have been chosen as pilot projects to determine whether farmers can, and will, voluntarily change what they do on the land to clean up the nation’s water.

State and federal officials on Monday announced the sites of four projects that will be the first in a program that is looking for farmers willing to adopt precise on-the-ground plans for protecting the water from agricultural pollutants.

“Our farmers will not only be improving our state’s water quality, but they’ll also get some certainty over conservation regulations while they’re in this program,” said Minnesota Sen. Al Franken, who attended a news conference about the project with Gov. Mark Dayton, U.S. Agriculture Secretary Tom Vilsack and others. “It’s farming done right, and it’s conservation done right.”

The Minnesota Agricultural Water Quality Certification Program, first announced a year ago, will combine $3 million in state Legacy funds with $6.5 million in federal funding. It is the first test of a new strategy designed to stem the flow of agricultural pollution strangling some of the nation’s great bodies of water, including Chesapeake Bay, the Gulf of Mexico and the Mississippi River.

Minnesota has a “quality of life that depends on outdoor recreation,” said Minnesota Assistant Agriculture Commissioner Matt Wohlman, in addition to relying on clean rivers for drinking water and wildlife habitat. Its economy, however, depends on agriculture.

“It doesn’t have to be a false choice of one or the other,” Wohlman said. “It can be both. And I think it has to be both.”

Imposing environmental rules on agriculture — the primary source of unregulated water pollution in Minnesota — faces challenging political hurdles.

At the same time, long-standing farm programs that encourage conservation are in decline — the victim of both budget cutbacks and rising commodity prices that encourage farmers to plant even on environmentally sensitive land.

Those trends have caused water-quality and conservation advocates to challenge the wisdom of relying on voluntary efforts to stem agricultural pollution. Regulators have long known the sources of sediment, nitrogen and other agricultural contaminants, but measured pollution levels have not improved, they say.

The sites announced Monday are agriculturally intense watersheds that feed the Whitewater River in southeastern Minnesota, Elm Creek in south-central Minnesota, the Middle Sauk River in central Minnesota and Whiskey Creek in the northwestern part of the state.

They were chosen because the type of farming in each is fairly consistent and because state officials have good data in each that allows them to measure changes in water quality, Wohlman said.

Starting this summer, local officials will recruit farmers, analyze their specific land use and water-quality problems, and design strategies to help mitigate them, he said.

For example, if a region has too much nitrogen in the water, the plan will include ways to reduce it. The money will help farmers pay for the changes they make — such as planting cover crops to slow erosion or installing conservation systems on their field tiling to slow runoff.

Whether the experiment works will be measured through changes in water quality three years down the road.

Those who participate will be exempt for 10 years from new regulatory changes in water-quality requirements, giving them some financial assurance that the investments they make will have some longevity, he said. And they will be measured on how well they are doing by a water-quality index that is being developed by the Minnesota Department of Agriculture.

“But at end of the day, the measurable result is whether our water is getting cleaner or not,” he said.