A March 2011 appeals court decision held that the flow of water from one portion of a river through an engineered improvement into a downstream portion of the same river constitutes a regulated discharge of pollutants under the Clean Water Act (CWA). By this ruling, a National Pollutant Discharge Elimination System permit would be required. Get more details about this case.

On Sept. 11, the Water Environment Federation and others on Sept. 11 filed a friend-of-the-court brief with the U.S. Supreme Court supporting the position that such a scenario does not constitute a “discharge” for purposes of CWA. The brief argues that the Supreme Court should reverse the 9th U.S. Circuit Court of Appeals ruling to avoid serious negative consequences for public agencies and authorities nationwide involved in water management for water supply, flood control, and related public purposes.

The Supreme Court has previously ruled that transfers of water from one section of a waterbody to another do not qualify as a CWA discharge requiring a permit. The Supreme Court is scheduled to hear oral arguments in the case Dec. 4.