A Biden administration won’t be able to untangle the legal and regulatory “mess” under part of the Clean Water Act that determines which streams, wetlands and other waters get federal protection, legal scholars and litigators say.

Any move the Biden administration takes to clarify the definition of Waters of the United States, known as WOTUS, will continue the decades-long “merry-go-round” of administrative rule changes and litigation, said Larry Liebesman, a former Justice Department environmental lawyer who is now a senior adviser at the environmental and water permitting firm of Dawson & Associates.