The U.S. Supreme Court’s decision last week to leave in place an expansive U.S. Environmental Protection Agency water pollution control program fo the Chesapeake Bay watershed may encourage the EPA to craft similarly sweeping plans for the Great Lakes and other regions.

The American Farm Bureau Federation had asked the high court to overturn on 2015 Third Circuit decision upholding a district court’s approval of the Chesapeake Bay Total Maximum Daily Load (TMDL) plan, an effort to control water pollution in the bay that took years to craft.

“The Farm Bureau’s argument was that if the Chesapeake Bay TMDL was approved, it would provide the blueprint for the EPA to do this in some of the other large watersheds, such as the Great Lakes and other watersheds in the West. So I think it absolutely opens the door up for the EPA to do that elsewhere,” said Steven R. Johnson, of counsel at Ballard Spahr LLP and the former principal counsel fo the Maryland Department of the Environment.

Mr. Johnson said that a typical TMDL is a numerical load that the receiving water can assimilate. In the Chesapeake Bay plan, the TMDL is more broadly defined, including specific allocations among 92 different watersheds across seven jurisdictions.

The plan is likely to spur big changes in how states and localities control pollution and will probably drive growth in the nutrient offset market, where sources can sell offsets gained by reducing pollutant discharges, Mr. Johnson said. Pennsylvania and Virginia laready have nutrient trading programs, and Maryland is developing one.

“A lot of people view it as a way to get the agricultural community on board with nutrient reductions, if that can be monetized through generating credits that can be sold to wastewater treatment plants that need to increase their allocation,” he said.