More local farms may fall under big-farm pollution regulations.
And local municipalities and developments may be required to do a better job of containing storm water and keeping it out of streams.
Both measures are being sought by the U.S. Environmental Protection Agency, which Monday announced the latest round of tougher regulations designed to clean up the Chesapeake Bay.
President Barack Obama in May issued an executive order to clean up the Chesapeake Bay after two decades of failed commitments from states and the federal government to do so.
"We're developing the most rigorous framework to date for reducing pollution in the bay and its watersheds," EPA Administrator Lisa P. Jackson said in announcing the new federal rules.
"These rules will provide critical backstop measures to ensure accountability in state efforts that are the front line for success in this historic cleanup effort."
But at least one top Pennsylvania environmental official expressed concerns that a tougher federal hand might undo the state's preference to work at the local level for cleanup of streams.
"We have concerns," said John T. Hines, the state Department of Environmental Protection's deputy secretary of water management.
EPA said it would seek stringent regulations to more effectively get large farms in Pennsylvania, Maryland, Virginia and New York to reduce nutrient pollutants than can run off farmland and into streams that feed the Bay.
EPA said it would consider "expanding the universe" of concentrated animal feeding operations, meaning smaller farm operations may be brought under the umbrella of the stricter pollution controls currently on only the largest farms.
Currently, Pennsylvania has about 340 CAFO farms, as determined by the number of animals.
EPA is considering designating farms on the basis of the number of discharge pipes on the farms, not just animals, according to Hines.
"I don't know if that is the best approach for us," he said.
Pennsylvania has been trying to aid farmers financially to help them with on-farm conservation measures so that they can come into compliance, he said.
"Then we would seek options on enforcement for the recalcitrant ones. I don't think anyone would disagree with that," he said.
Also to be considered by EPA are options that would improve how surplus manure is spread or stored and streamlining the designation process.
"We think our nutrient management regulations cover that," Hines said in reaction to the proposal.
EPA said it hoped to propose the new rules in 2012 and have them in effect by late 2013.
New regulations on municipal storm water controls could have a big impact on local communities.
Not only would more storm-runoff controls be required on newly developed and redeveloped sites, but EPA said it might impose tougher regulations on communities in the bay watershed than found in the rest of the nation.
Also, the regulations may be levied on smaller sites than in the past.
Hines said he is concerned that effective efforts to minimize urban runoff by working on a county or regional level may be disrupted by tougher regulations imposed on each borough, city or township.
Plus, forcing already developed sites, such as a housing development or office complex, to try to reduce more runoff could be a problem.
"You are looking at some of our older communities. How do you retrofit, and how do communities afford it?" Hines said.
Hines did have favorable things to say about another EPA initiative that would allow pollution load offsets.
Under new pollution limits each waterway in the state will have, development could be prohibited if it would lower a stream's water quality.
The offset measure would allow such projects to go forward if the developer could improve stream quality elsewhere. Planting a riparian buffer along a stream might be one such measure.
"The important thing here is we have to work with partners," Hines said.