The Obama administration proposed new guidelines Wednesday that would boost the government's ability to protect streams, wetlands and other sensitive waterways from pollution.
Business and property rights groups said the policy would stifle economic growth by generating more red tape for builders of homes and shopping centers, but environmentalists defended it as essential step to provide clean drinking water and protect waterfowl habitat.
Administration officials said their goal was to clarify which waters are subject to federal regulation under the 1972 Clean Water Act, a question that two Supreme Court rulings in the past decade have not resolved.
"Today about 117 million Americans _ more than a third of the U.S. population _ get their drinking water in part from sources that lack clear protection from pollution," Environmental Protection Agency chief Lisa Jackson said. "At the same time, businesses and regulators face uncertainty and delay" when seeking development permits.
EPA and the Army Corps of Engineers said the plan would not take effect until after a 60-day public comment period. Even then, it won't have the force of law, although field staffers will refer to the document when considering whether they have jurisdiction over particular waterways. The agencies' next step will be developing a set of binding regulations, Jackson said.
The guidelines appeared likely to escalate tension between EPA and Republicans in Congress, who have accused the agency of exceeding its authority on greenhouse gas regulation and other issues. House Agriculture Committee Chairman Frank Lucas, R-Okla., said the plan would let the government "regulate essentially any body of water, such as a farm pond or even a ditch."
A bipartisan group of 170 lawmakers urged the agencies in a letter last week not to release the guidelines. Others said they were needed because the Bush administration had misinterpreted court rulings and lifted protections for crucial waterways, including thousands of miles of streams and at least 20 million acres of wetlands.
The changes do not remove any existing exemptions from Clean Water Act for activities such as farming and logging but they restore environmental protections that had long been recognized, said Scott Kovarovics, conservation director for the Izaak Walton League of America.
"The administration's approach is balanced and reasonable," Kovarovics said.
In a 2006 case from Michigan, the Supreme Court attempted to define which waterways the law covers. But the justices were so sharply divided that they produced five separate opinions and no clear majority. The controlling opinion by Justice Anthony M. Kennedy said the government could assert jurisdiction over a wetland if it had a significant connection to a navigable waterway.
Differing with the Bush administration, Obama's team interpreted the court ruling as letting regulators analyze a proposed development's effect on entire waterway networks instead of just individual streams or wetlands, said Jim Murphy, an attorney with the National Wildlife Federation.
Officials said water bodies would be covered if they have "a significant physical, chemical or biological connection" to an interstate or navigable waterway. Among those excluded from protection: artificial lakes or ponds, including farm and stock ponds, and most roadside ditches and gullies.
Environmental law experts said the government had made a good-faith attempt to help regulators navigate a confusing path.
The White House is "moving ahead with water issues that have languished for years," said Gerald Galloway, a water resources specialist at the University of Maryland. "They're taking on the tough ones."
But Oliver Houck, an environmental law professor at Tulane University in New Orleans, said the administration's roadmap would be difficult and costly to enforce.
"It's a like a 19-page recipe for a cake," he said.
Associated Press writers Cain Burdeau in New Orleans and Dina Cappiello in Washington, D.C.,. contributed to this story.