Before House Republicans approve a $1 trillion spending bill to keep the government open past Thursday night, they are making a few demands. Hampering the Environmental Protection Agency's ability to regulate is one of them.

Republicans and Democrats are still negotiating over exactly what the bill will look like, with a vote coming as late as the weekend—even though Thursday is the last day of the session. But based on a New York Times report, one of the top issues at stake is regulations under the Clean Water Act. The EPA proposed a Waters of the U.S. rule this spring to answer a question that has been unclear in the last decade of the Clean Water Act’s 42-year existence. It subjects unregulated streams and wetlands to new restrictions—and that has made conservatives furious. In the last few months, the EPA has released long-awaited regulations on water, coal, and smog, all of which have riled Republicans. They are hoping to add riders to the bill that restrict the EPA’s authority to enforce these rules.

If this battle sounds familiar, that's because shutdown threats over EPA-related regulations have happened a few times before. Even if the EPA emerges from these negotiations unscathed, the debate will return next year in the Republican Congress. The next Senate Majority Leader Mitch McConnell has suggested attaching riders to appropriations bills will be the GOP's preferred strategy to undo President Barack Obama's climate plans in his two final years.