U.S. regulators aim to repeal a contentious Trump-era rule that stirred fierce opposition from conservationists and many New Mexico leaders because it removed most of the state's water from federal protection.
The Environmental Protection Agency's head said the agency and the Army Corps of Engineers had determined the rule was causing substantial harm to water bodies and pointed to New Mexico and Arizona as among the states most affected.
The current rule, which has spurred a string of lawsuits, only protects waterways that flow year-round or seasonally and connect to another body of water.
It excludes as "ephemeral" storm-generated streams as well as tributaries that don't flow continuously to another water body - disqualifying most of New Mexico's waters. Unregulated storm runoff can carry contaminants into rivers used for drinking water, conservationists say.
Water advocates see the announced change as an encouraging move, but warned it will take time to repeal and replace the rule. In the meantime, they say potentially harmful projects already approved will move forward.
"I think many people remain concerned that the Trump rule remains in place, and that waters can be injured because of it," said Cliff Villa, associate professor and supervising attorney for the University of New Mexico's Natural Resources and Environmental Law Clinic.
Under Villa's guidance, a group of law students filed suit on behalf of Laguna and Jemez pueblos with the aim of persuading the federal courts to vacate the rule - partly because overturning regulations can take years.
It took the Trump administration three years to undo the Obama-era clean water rule, although some delay was caused by a former EPA head's missteps while trying to rush it through, Villa said.
One water advocate said she thinks the repeal can be done relatively quickly.
After the EPA states its intention to scrap "the dirty water rule" in the Federal Register, a 30-day public comment period will follow and then the agency can work to repeal it, said Rachel Conn, projects director for Taos-based Amigos Bravos.
Establishing a new rule will take considerably more time, Conn said, but in the meantime it's crucial to get rid of a standard that is leaving most of New Mexico's waters unprotected.
"The rule is having serious harm now to our waterways," Conn said.
Conn and other critics of the current rule have worried it would nix the EPA's oversight of heavily polluted runoff from Los Alamos County into the Río Grande - a prime source of drinking water - and that it might disqualify the Gila River from protection because that waterway runs dry before reaching the Colorado River.
"After reviewing the Navigable Waters Protection Rule as directed by President Biden, the EPA and Department of the Army have determined that this rule is leading to significant environmental degradation," EPA administrator Michael Regan said in a statement.
The lack of protections is especially significant in arid states such as New Mexico and Arizona, where nearly every one of over 1,500 streams has been found to be outside federal jurisdiction, the EPA said in a news release.
Regan said the agency is committed to creating a "durable definition" of U.S. waters based on Supreme Court precedents, learning from past regulations and getting input from a variety of interested parties. The agency also will consider the impacts of climate change, he said.
In an emailed statement, Gov. Michelle Lujan Grisham said the rule would devastate New Mexico's waters. "We are grateful to Administrator Regan for recognizing the disproportionate impacts of the rule to New Mexico," she added. "And we are hopeful that meaningful protections will be restored under a revised, long-lasting rule based on sound science and robust state, tribal and stakeholder engagement.
New Mexico is one of just three states that has no authority from the EPA to regulate discharges of pollution into rivers, streams and lakes under the Clean Water Act, which leaves it at the mercy of whomever is in the White House, Conn said.
A longtime environmental attorney said he is optimistic about the shifting political tide, even if replacing the rule takes time.
If the rule is repealed, the regulations will revert to more stringent ones enacted in 1987, said Charles de Saillan, staff attorney for the New Mexico Environmental Law Center.
Conn and de Saillan are among several parties involved in suing the EPA over its navigable waters rule.
Congress should intervene and create well-defined and permanent updates to the Clean Water Act to stop the political seesawing that happens every change of administration, de Saillan said.
Congressional action would be much better than having the U.S. Supreme Court make rulings on it, de Saillan said. The last high court decision on which waters merited federal protection was ambiguous, causing more confusion and legal battles, he said.
"The Supreme Court is not the place to resolve this," de Saillan said. "That would be unfortunate."