She said the rule changes would clarify which bodies of water are covered and will reduce confusion created following Supreme Court rulings in 1986, 2001 and 2006. It also clarifies what’s covered in the Clean Water Act.

“The U.S. Supreme Court has reviewed the agencies’ regulatory definition of “waters of the US” three times,” she said. 

The first time was in Riverside Bayview Homes, 1986.  A unanimous Supreme Court upheld the agencies’ regulatory definition and talked about the integrated nature of the aquatic ecosystem and the importance of adjacent wetlands to that ecosystem.

In a 2001 case called SWANCC, the Supreme Court held that the CWA did not authorize considering something as a “water of the US” based solely on the water’s use by migratory birds.  “While the SWANCC decision did not invalidate the agencies’ regulations, it emphasized that some type of relationship with waters that were navigable was necessary.” 

The latest Supreme Court case in 2006 considered the scope of “waters of the US” in the Rapanos and Carabell decisions.  The Court’s decision was split, with five opinions and none having a majority of votes.

Stoner says the clarifications in the proposal will save businesses time and money. The rule changes will also help states protect water. “Currently, 36 states have (legal) limitations on their ability to protect water that’s not covered by the Clean Water Act,” she said.

She also explained what the rule does not do.

“It does not protect any new types of water. It does not broaden the historical coverage of the clean Water Act. It does not regulate groundwater or expand regulation of ditches. It does not remove any exemptions.

“The rule actually proposes to reduce jurisdiction by excluding certain ephemeral and intermittent ditches. In fact, every exemption currently in the statute or regulations is preserved,” Stoner said.