(New Mexico News Connection) A favorable ruling in a case before the U.S. Supreme Court challenging the federal Clean Water Act could remove protections nationwide, and affect 90 percent of streams in New Mexico. The high court heard oral arguments last year in Sackett versus the Environmental Protection Agency, with a ruling expected any day. It dates back 14-years when the EPA halted construction on an Idaho home owned by Michael and Chantell Sackett, arguing it jeopardized protected wetlands. 

Rachel Conn, deputy director of Taos, N.M.-based Amigos Bravos, said an arid state like New Mexico is in the crosshairs.

"Many of our streams are small and these administrative actions have really focused on stripping away protections from smaller waterways and that's really basically all of our waterways here in New Mexico," Conn said.

If the Supreme Court rules against the EPA, it's estimated the drinking water of one in three people across the country would be at risk.

A study by the Tulane Institute on Water Resources Law and Policy concluded a favorable ruling for the Sackets could have wide-ranging impacts and leave wetlands management up to states. Conn added that is a problem in New Mexico, which is one of only three states without a surface water quality permitting program - which could leave its wetlands with the fewest protections. 

"We may not have many of them, but they do a lot of work to protect our watersheds - they filter out pollution, they help maintain stream flows, they provide wildlife habitat, so they're critically important to the functioning of our watersheds overall," she explained. 

In 2019, the EPA released its revised "Waters of the United States" rule to restrict what falls under the purview of the 50-year old Clean Water Act. It was scrapped by the Biden administration a year later, and Conn said New Mexico environmentalists were relieved. 

"Up to 96 percent of our waterways were left unprotected under Trump administration interpretations of previous Supreme Court decisions about this issue," she added. 

Conn said indigenous and low-income communities in New Mexico - those who already suffer the most from toxic water pollution - would be especially impacted by a ruling in favor of the Sacketts.