WASHINGTON -- The Trump administration proposed withdrawing federal protections for countless waterways and wetlands across the country Tuesday, making good on President Donald Trump's campaign pledge to weaken landmark Obama-era water rules long opposed by some developers, farmers and oil, gas, and mining executives.

The scaling back of federal oversight is "recognizing and respecting the primary authority of states and tribes" over the waterways, R.D. James, assistant secretary of the Army for civil works, said during a ceremony at EPA headquarters.

Environmental groups said the Trump administration proposal would have a sweeping impact on how the country safeguards the nation's waterways, scaling back not just a 2015 Obama administration interpretation of federal jurisdiction, but how federal agencies enforce the 1972 Clean Water Act.

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"The Trump administration has just given a big Christmas gift to polluters," said Bob Irvin, president of the American Rivers environmental nonprofit. "Americans all over the country are concerned about the safety of their drinking water -- this is not the time to be rolling back protections."

The changes would affect what waterways and wetlands fall under jurisdiction of the EPA and the U.S. Army Corps of Engineers. The Trump administration would remove federal protections for wetlands nationally unless they are connected to another federally protected waterway, and for streams, creeks, washes and ditches that run only during rains or snow melt.

Interior Secretary Ryan Zinke said the proposal "doesn't remove any protection."

"It puts the decision back where it should be, the people that work the land, that hunt, that own the land," Zinke said.

Dozens of congressional Republicans and state legislators joined heads of the American Farm Bureau Federation and industry groups in praising the latest Trump administration environmental regulatory rollback.

"When you have uncertainty and overreach it makes it incredibly difficult to build American homes," Gerald Howard, the CEO of the National Association of Home Builders, said of the Obama administration's interpretation of the water rules.

Jan Goldman-Carter of the National Wildlife Federation said the move could remove federal protections for millions of miles of wetlands and waterways, leaving them more vulnerable to destruction by developers and farmers or to oil spills, fertilizer runoff and other pollutants. Wheeler said there was no firm data on what percentage of waterways would lose protections.

Environmental groups say the kind of isolated wetlands, runoff-fed streams and often dry washes that would lose federal protections also help buffer communities from the worsening impact of drought, floods and hurricanes under climate change, and are vital for wildlife.