The federal government is limiting which bodies of water are eligible for protection under the Clean Water Act.
Now, Colorado is working on its own set of rules for places that will no longer be federally protected, following a 2024 bipartisan law. The nonpartisan Western Resource Advocates estimates that these new rules will apply to over 68% of Colorado rivers and drinking water sources, and nearly all of the state's wetlands.
Stu Gillespie, a senior attorney with EarthJustice, said that for the last couple of decades, the court used what was called the "significant nexus" test to determine whether a body of water would be subject to the Clean Water Act.
"If a stream or wetland had a nexus to a downstream water, if it impacted it, it was covered by the Clean Water Act," he explained. "That was under the recognition that if that headwater stream is impacting downstream waters, we should be protecting it."
But in its 2023 ruling in Sackett vs. EPA, he said the Court took a much narrower approach to regulation.
"It said, 'we are only going to protect streams that are relatively permanent, and we're only going to protect wetlands that have a continuous surface connection to those streams,' and so that vastly narrowed the scope of the Clean Water Act."
Gillespie said the Trump administration is currently reinterpreting the Sackett ruling to make the waters it applies to even narrower, by proposing new definitions for the Waters of the United States and therefore further constraining the scope of the Clean Water Act.
"I think we've gotten to the point now where in Colorado, only about 3% of our wetlands would be protected," he said. "So this is a continuing problem at the federal level, and that underscores the … need to set up this state program and make sure we have those comprehensive protections."
The Sackett ruling, along with the new proposal to only protect permanent rivers and wetlands directly connected to them, poses a problem for Colorado and other Mountain West states. Because of the region's reliance on snowmelt for much of its water supply, bodies of water are often ephemeral, or intermittent.
"This Sackett decision and the Trump administration proposal just does not work for Western states where we're tied to snowmelt, in most cases, for the bulk of our water, including water that we drink and irrigate fields with, and that nourishes our wildlife habitat," said Joro Walker, a senior attorney with Western Resource Advocates.
She said there's special concern for Colorado's wetlands, because of how drastically federal protections have been cut.
"All waters are interconnected, but wetlands are very important because, in addition to providing habitat, they clean water, they mitigate floods, and provide recreational opportunities," she said. "So it's critical to protect wetlands in particular, and because of the narrowing of the scope of the Clean Water Act, almost all wetlands in the state are left unprotected."
Both Gillespie and Walker are representing different groups in Colorado's rulemaking process for its drinking water.
Colorado's water quality rulemaking
A big part of Colorado's new program to create protections for its water and wetlands is regulations for dredging and filling activities. Some of the activities that involve dredging or filling streams include mining, oil and gas development, and canal, reservoir and ditch construction, among others.
Gillespie used the example of a mining company that would have to dredge and fill streams and wetlands in order to begin operations. That company would now have to go to the state to get a permit, which Colorado's Water Quality Control Commission would then evaluate. He said it's likely that state officials would ask the company to avoid the streams and wetlands altogether.
"Let's look at alternative ways that we can design this project to maybe minimize those impacts or even avoid them," he said of the state's thinking. "If that can't be done, then we're going to look at what the impacts are both at that site and downstream. How are you impacting communities? How are you impacting wildlife, how are you impacting habitat? We're going to analyze that and we're gonna require you to mitigate it."
Gillespie said the end goal is that projects that involve dredging don't disrupt the function of the state's streams and wetlands.
"So you can continue with your project, but you have to do this additional work to make sure it's done the right way."
Gillespie and Walker agree that Colorado's new rules are especially important as the state considers the impacts of long-term drought and human-caused climate change.
"Water is Colorado's most critical natural resource, and that's only truer in a warmer climate," Gillespie said. "And I think one of the perverse results of the Sackett decision is that as our streams and wetlands get drier, they're actually losing federal protections."
Walker said that wildlife habitat is especially vulnerable to these changes.
"Then we add to that the increased pressures from population increase," Walker said. "That means there's more demand for development, but it also means that there's more demand for water. So it's kind of a double whammy. And then you add to that the impacts of climate change. And you can imagine that based on those pressures that impacts to wildlife habitat are, are only going to increase."
The hearing for Colorado's rulemaking process on the dredge and fill program will take place on Monday, Dec. 8th. The public has until Thursday, Dec. 4th to sign up to comment during the hearing.
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