A Trump administration rule reducing what streams and other waters are subject to federal environmental protections takes effect in Colorado today, following an appeals court action on a legal challenge to the rule by Colorado Attorney General Phil Weiser.

Last year the EPA and Army released the Navigable Waters Protection Rule, governing protections of what are referred to as “waters of the United States” under the Clean Water Act. It cut back the reach of what waters are covered under the law. The rule applies protections in cases such as traditional navigable waters, perennial and intermittent tributaries to those waters, and some wetlands, lakes and impoundments. But it provides exemptions in cases such as groundwater, ephemeral streams that flow only due to rainfall, many ditches, and waters pertaining to prior converted cropland.

The Water for Colorado Coalition said in a news release this week that the Trump rule leaves at least 25% of Colorado’s streams and 22% of its wetlands vulnerable to pollution, and particularly hits seasonal, ephemeral streams hard, with those streams making up 68% of waters in the state.

The Trump administration previously had repealed a 2015 Obama administration measure expanding waterway and wetland protections beyond protections established in 2008. The Obama measure had support from conservation groups but was opposed as overreaching by agricultural and other industries, and by others including Club 20 and former U.S. Rep. Scott Tipton and U.S. Sen. Cory Gardner, Republicans then representing Colorado in Congress.

The Trump administration said its 2020 rule ended decades of uncertainty regarding the extent of federal jurisdiction under the Clean Water Act and removed undue regulatory burdens for farmers and other landowners.

Weiser and Colorado Gov. Jared Polis, both Democrats, voiced support last year for a few elements of the Trump-era rule, including its agricultural exemptions, but they objected to much of it and Weiser took legal action. Based on that action, the U.S. District Court of Colorado had issued a stay barring the 2020 rule’s implementation in Colorado, but the 10th Circuit Court of Appeals recently lifted that stay. Before today, Colorado had been the only state in the country where the Trump rule didn’t yet apply.

In its news release, the Water for Colorado Coalition said Colorado “needs state policies protecting clean drinking water and our waterways more broadly regardless of who is in the White House. While policy changes in the new federal administration could reestablish protections, that will take years — by then, the damage done to our waters will be irreparable. If Colorado leadership doesn’t step in, streams and wetlands could be filled with construction debris, subject to polluted runoff from nearby development sites or obliterated by bulldozers.”

The Polis administration, through the Colorado Department of Public Health and Environment and its Water Quality Control Commission, is working on pursuing passage of legislation to help protect waters the Trump rule leaves unprotected.

According to a memo to the Colorado River District board this week from its legal staff, the WQCD “believes a state-run dredge and fill permitting system is necessary to cover these ‘gap waters.’ ”

The district attorneys added said, “We are monitoring this closely and believe that if any state program is adopted, it should include clear exemptions for construction and maintenance of agricultural ditches and ponds, including piping projects and the construction of regulating reservoirs.”

Zane Kessler, the river district’s government relations director, told the board it appears the state is having some trouble finding legislative sponsors for a draft bill addressing the “gap waters,” and he’s hearing concerns about the bill from a number of water users and legislators.

“The path forward on this (bill) is very unclear,” he said.

Meanwhile, river district staff are monitoring a 2020 EPA and Army Corps of Engineers policy that no longer exempts piping and lining of earthen ditches from one Clean Water Act permitting requirement.

The district is pushing for reversal of that change, or an ability for such projects to be covered by a nationwide or regional permit to reduce the regulatory burden for projects that have been used in Western Colorado to improve water quality and efficiency.