The rule defines which “waters of the United States” are protected by the Clean Water Act. For decades, the term has been a flashpoint between environmental groups that want to broaden limits on pollution entering the nation’s waters and farmers, builders and industry groups that say extending regulations too far is onerous for business.
The Environmental Protection Agency and the Department of the Army said the reworked rule is based on definitions that were in place prior to 2015. Federal officials said they wrote a “durable definition” of waterways to reduce uncertainty.
In recent years, however, there has been a lot of uncertainty. After the Obama administration sought to expand federal protections, the Trump administration rolled them back as part of its unwinding of hundreds of environmental and public health regulations. A federal judge rejected that effort. And a separate case is currently being considered by the Supreme Court that could yet upend the finalized rule.