The Biden administration is set to toss out President Donald Trump’s efforts to scale back the number of streams, marshes and other wetlands that fall under federal protection, kicking off a legal and regulatory scuffle over the fate of wetlands and waterways around the country, from the arid West to the swampy South. Michael Regan, head of the Environmental Protection Agency, said his team determined that the Trump administration’s rollback is “leading to significant environmental degradation.” The EPA and Army Corps of Engineers will craft a new set of protections for waterways that provide habitats for wildlife and safe drinking water for millions of Americans, according to a joint statement.

With the announcement, the Biden administration is wading into a decades-long battle over how far federal officials can go to stop contaminants from entering small streams and other wetlands.

Some Republican lawmakers accused the Biden administration of wanting to return to Obama-era clean-water rules and burden farmers, real estate developers and other businesses with new restrictions on how they can use their land.

“This is a gut punch to Iowans, and I will continue to stand up to onerous regulations the administration may seek to impose on our hard-working families,” said Sen. Joni Ernst (R-Iowa).

In 2015, the Obama administration expanded federal authority to stop or curtail development that could harm a variety of wetlands, streams and ditches that feed into larger bodies of water protected under the Clean Water Act.

Heeding the call of home developers, oil drillers and growers who saw the restrictions as detrimental to their livelihoods, the Trump administration rolled back those Obama-era pollution controls.