Federal agencies must reconsider an Obama-era rule that tweaked the definition of the type of waterway that qualifies for environmental protection after a Galveston federal judge issued a preliminary injunction Tuesday in a lawsuit by three states and 17 trade associations.

The case, Texas v. U.S. Environmental Protection Agency, attracted widespread interest and amicus briefs came from an environmental group, business groups, Washington, D.C., and states including New York, Connecticut and California. There's also similar litigation across the country over which waters adjacent to protected waterways fall under federal jurisdiction, and the U.S. Army Corps of Engineers and U.S. Environmental Protection Agency are already working on a replacement because of an executive order by President Donald Trump.

The litigation objected to the Obama-era rule's definition of “adjacent waters” near an environmentally protected waterway such as a river that crosses multiple states. Rather than relying on ecological or hydrological criteria to determine what's an “adjacent water,” the rule said an adjacent water is located a certain distance from the protected river, changing a decades-old definition.

Congress passed the Clean Water Act in 1972 to protect the country's water by making it illegal to discharge pollution into “waters of the United States” and seas. The act didn't define “waters of the United States,” but the U.S. Army Corps of Engineers in 1986 defined the term. In 2014, the Corps and the U.S. Environmental Protection Agency proposed a new definition and provided public notice and a public comment period on the proposal, but when it issued its final rule in 2015, one part of the definition was significantly different than the proposal.

This prompted Texas, Louisiana and Mississippi, joined by 17 trade associations, to sue the U.S. EPA and the Corps, and those agencies' leaders during the Obama Administration, over the new definition of “waters of the United States.”

The plaintiffs alleged the final rule violated the administrative procedures act, clean water act, commerce clause and Tenth Amendment of the U.S. Constitution.

U.S. District Judge George Hanks Jr. of the Southern District of Texas ruled that the final rule violated the Administrative Procedures Act, which requires public notice and public comments before an agency may issue new rules. The final rule's new definition of “adjacent waters” was significantly different from the initial proposal, and interested parties were deprived of notice about the change and the chance to comment on a technical study the agency used for the “adjacent waters” definition, the opinion said. The court granted the plaintiffs summary judgment on that one issue, but didn't address their substantive challenges to the final rule.

Although the plaintiffs wanted the court to vacate the rule, it instead remanded the rule to the agencies to provide notice and a comment period on the rule.

“Remand is the best remedy here as it will facilitate the agencies' active attempts to improve on their work of protecting the environment and bringing predictability and clarity to the definition,” the opinion said.

The court had previously enjoined enforcement of the rule, and so have district courts in many other jurisdictions, said a statement by the Texas Office of the Attorney General.

The new definition would have expanded the reach of the Clean Water Act in a way that harms Texans and the state economy, the statement said.

“This critical federal court decision is a major victory for the people of Texas' ability to regulate their own natural resources, including ponds, puddles and streams on private property, and a major win for property owners, whose land would have been subject to unlawful and impractical EPA regulations,” said Texas Attorney General Ken Paxton.

No one from the press offices of the U.S. Army Corps of Engineers or the U.S. EPA returned messages seeking comment before deadline.

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