The U.S. Agriculture Department will put up $33 million for grants and technical assistance to help American farmers and ranchers take steps to stop polluted storm runoff from gushing into 157 watersheds, including a small portion of the Chesapeake Bay.

Agriculture Secretary Tom Vilsack announced the Water Quality Initiative on Tuesday to improve “impaired watersheds in every U.S. state and territory.” Vilsack called the push “a bold step . . . to improve water quality in some very challenging watersheds.”

Starting May 18, farmers, ranchers and forest landowners can apply for a grant and other assistance in what Natural Resources Conservation Service Chief Dave White called a highly competitive process. Those in the eligible watersheds can apply by scheduling an appointment at their USDA service center or with a state conservationist. Applications for the program must be submitted by June 15.

White said the eligible watersheds were chosen by state water quality agencies from a list of impaired waterways provided by the Environmental Protection Agency.

Maryland chose the upper, middle and lower Catoctin Creek, a tiny portion of the Potomac River watershed in Frederick County that flows into the Chesapeake Bay. Virginia selected Mollys Creek, a subwatershed of the Roanoke River in Campbell County; Somerton Creek, part of the Chowan River watershed at the North Carolina border; and Wolf Creek, in the South Fork Holston River watershed at the Tennessee border.

The NRCS, which is providing the funds, will work with state and federal partners such as the EPA and U.S. Geological Survey to determine the program’s results. It is meant to complement pollution reduction efforts underway in the Mississippi River Basin, the Great Lakes, the Chesapeake Bay and other regions.

Rivers and streams are usually considered impaired when their waters are awash with nitrogen, phosphorous, sediment and algae blooms, such as the pollution in the Chesapeake. The pollution harms fisheries by sucking out oxygen, which creates dead zones and threatens the quality of drinking water.

Water quality officials in Texas will protect a freshwater reservoir that serves 1.8 million residents of Fort Worth. Hundreds of millions of Americans rely on rivers and streams for drinking water. Sources of fresh water pollution are manifold — point source pipes from coal-fired power plants, urban and suburban sewers, concrete surfaces from development that send tainted rain runoff into waterways like a flume, and non-point source farm fertilizers and animal manure that get washed away by storms.

Wealthy power plant owners, city sewer managers and housing developers are better able to pay for conservation efforts that stop or soak up wastewater, but many farmers are hard-pressed to pay for cover crops, terraces and pollution-fighting buffers.

“American farmers are good stewards of the environment, and this initiative provides them with additional tools to protect and improve fish and wildlife habitat and water quality,” Vilsack said in a statement.

Distributed nationwide, $33 million only goes so far. Awards will be capped at $300,000, Vilsack said, and most will probably fall short of that.

But other partners such as the Maryland Department of the Environment and Virginia Department of Conservation and Recreation are stepping up with supplemental award programs for farmers, White said.

“The purpose is to create catalyst, an incentive to attract sister agencies, . . . sports groups and conservation groups” to help, “hopefully working in concert,” Vilsack said.