“One of the worst examples of federal regulation.”

Those are the words that US President Donald Trump used to describe a law that protects the water sources of 117 million Americans. Now, he is trying to repeal it.

The Waters of the United States regulation (also known as — yep — WOTUS), seeks to protect drinking water sources from pollution. Overall, it covered about 60% of the nation’s bodies of waters. But Trump and Scott Pruitt, the head of the Environmental Protection Agency, are trying to undo the rule, which they say puts too much regulatory control in the hands of the federal government.

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For environmentalists, WOTUS, passed by the Obama administration, was an important step toward halting industrial pollution and ensuring the universal right to clean water for American citizens.

“This proposal strikes directly at public health,” Rhea Suh, the president of the Natural Resources Defense Council, an environmental advocacy group, told The New York Times. “It would strip out needed protections for the streams that feed drinking water sources for one in every three Americans. Clean water is too important for that. We’ll stand up to this reckless attack on our waters and health.”

For opponents of the regulation, it was an example of government overreach. Under the rule, the amount of water sources subject to federal oversight dramatically increases and many people worried that it would place an unfair burden on farmers, ranchers, and real estate developers who would be mired in red tape.

“The final WOTUS rule issued by the last administration was unworkable, a fact acknowledged by courts around the country, and amounted to a massive grab of regulatory authority by an EPA that was overreaching,” said Bill Kovacs, vice president for environment and regulatory policy at the US Chamber of Commerce.

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After being passed through the Clean Water Act in 2015, the regulation was immediately sued by states and industry groups. It’s been been tangled up in the courts ever since and hasn’t even been enacted yet.

But the Trump administration has made it clear that the current form of the rule will not proceed.  

Pruitt, the EPA director, issued a 42-page proposal to remove the rule. But it can’t simply be scrubbed from the books.

The EPA will now have to develop a legal case for why the rule should be removed, which will be challenged by environmental groups, and it will also have to develop a replacement rule.

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The replacement will likely feature less restrictions to stop pollution.

This is the latest effort by the Trump administration to roll back environmental protections.  Earlier in the year, a review to potentially end all the national monuments that cover 100,000 acres or more was announced, public lands were opened up for fossil fuel extraction, and wetlands were stripped of many of their protections.   

And, most notably, the administration withdrew from the Paris agreement, a global effort to curb the effects of climate change.

Now the administration is seeking to extend this pattern to the nation’s water supplies.

When nearly 25% of the country’s citizens don’t have access to safe drinking water from their taps, it seems that improving water quality would be a top priority, rather than a top target.