A federal judge issued a nationwide injunction Thursday against the Trump administration for delaying the Obama-era “Waters of the United States” rule, dealing a setback to a key piece of President Donald Trump’s deregulatory agenda.

The decision by the U.S. District Court in South Carolina means that the rule, also known as WOTUS and the Clean Water Rule, is again operative in 26 states where district courts have not halted the regulation.

The Obama administration rule, published in June 2015, intended to clarify which waters and wetlands are protected by the Clean Water Act and are subject to federal regulation by the Environmental Protection Agency and the Army Corps of Engineers. It in effect expanded federal oversight to smaller bodies of water than were previously covered, such as small streams, ponds and wetlands.

Farmers, ranchers, and developers said WOTUS violated their property rights, forcing them to protect the streams and tributaries that flow through their land.

In February 2017, President Donald Trump ordered the EPA to review the rule. During his campaign, he called WOTUS “one of the worst examples of federal regulation.”

Early this year, former EPA Administrator Scott Pruitt signed a regulation delaying WOTUS until 2020 to allow the agency to go through a process of rewriting a more modest version of it.

Environmentalists decried administration efforts against the rule.

“Instead of safeguarding our drinking water, the Trump administration is proposing to stop protecting drinking water sources for 3.7 million Coloradans,” Garrett Garner-Wells, state director for Environment Colorado, said last year. “It defies common sense, sound science, and the will of the people of Colorado.”

Tuesday’s ruling noted that the EPA avoided the customary 30-day waiting period between the rule’s finalization and its effective date, circumventing the Administrative Procedures Act, or APA.

“As administrations change, so do regulatory priorities,” said U.S. District Judge David Norton, an appointee of George H.W. Bush, in his ruling. “But the requirements of the APA remain the same. The court finds that the government failed to comply with these requirements.”

Molly Block, an EPA spokeswoman, said the agency is reviewing the judge’s order.

“EPA and the Army (Corps of Engineers) will review the order as the agencies work to determine next steps,” she told the Washington Examiner.

The Southern Environmental Law Center represented nine groups, including Charleston Waterkeeper and the Coastal Conservation League, in filing a lawsuit over the delay.

At the same time, 11 Democratic state attorneys general filed a similar lawsuit in the U.S. District Court for the Southern District of New York.

The EPA recently sent its draft replacement rule to the White House for review, and it should be made public soon.

Under the proposal, the EPA and the Army Corps would enforce the water regulations under the older, limited definition of waterways, which included primarily large bodies of water like rivers.

Colorado Politics contributed.