The western half of the Santa Fe River below the city's municipal reservoirs is usually dry, making it among the thousands of intermittent streams, wet meadows and ponds in New Mexico no longer protected from pollutants under the federal Clean Water Act.

Even Los Alamos National Laboratory might not need federal pollution discharge permits for storm water draining off the lab's waste dumps, according to Marcy Levitt, chief of the state Environment Department's Surface Water Quality Bureau.

Recent U.S. Supreme Court rulings and interpretations of those rulings by the U.S. Army Corps of Engineers and the Environmental Protection Agency have weakened protections under the Clean Water Act, Levitt said. That has the state Environment Department, sportsmen, wildlife protection groups and water advocates worried. They're lobbying Congress to support bi-partisan legislation introduced last year to restore those protections.

In the dry Southwest, isolated and seasonal pockets of water and wetlands are critical to the survival of migrating water fowl, songbirds, fish and deer and other wildlife, said Jim Murphy, of the National Wildlife Federation wetlands council.

The rollbacks of Clean Water Act protections leave those waters vulnerable to dredging, filling and pollution. "The situation is quite dire," Murphy said.

On Thursday, the National Wildlife Federation, Trout Unlimited, New Mexico Wildlife Federation and Ducks Unlimited released a report analyzing the impact of the Clean Water Act changes on the Southwest. "Our analysis reveals that about 90 percent of stream miles and 4,000 playa lakes in New Mexico are no longer assured basic federal safeguards against filling or toxics dumping," said Murphy, who co-authored the report. "These water resources are not renewable. Once they are gone, they are gone forever."

U.S. Supreme Court rulings in 2001 and 2006 appeared to strip protections from any waters that weren't connected to a navigable river or lake. It also appears interpretations of the ruling stripped protections from closed basins, where water flows in but not out, Levitt said. About 20 percent of New Mexico's waters are in such areas including in the Mimbres, Tularosa and the Salt basins underlying Otero Mesa.

Scott Yaich, conservation programs director for Ducks Unlimited, said wetlands were already at risk in the Southwest before changes to the Clean Water Act. New Mexico has lost a third of its wetlands, Texas half and California more than 90 percent, he said.

Those losses impact water fowl and wildlife.

In turn, the loss of more water habitat could impact hunters, anglers and wildlife enthusiasts, Yaich said. In New Mexico, more than a third of the population participates in one of those three activities, generating $808 million in revenue for the state last year.

New Mexico is among five states with waters that are particularly vulnerable to the loss of federal protection because they lack state primacy. Instead, permits for discharging into waterways or filling in waterways are handled by the EPA or the U.S. Army Corps of Engineers.

In Congress, 173 U.S. representatives including New Mexico's Tom Udall, a Democrat, joined sponsor Rep. James Oberstar, D-Minn., to support the Clean Water Restoration Act, which is currently in committee hearings. A related bill has been introduced in the Senate by Sen. Russell Feingold, D-Wis.

Contact Staci Matlock at 470-9843 or smatlock@sfnewmexican.com.