The Montana Supreme Court reversed, 5-2, a lower court decision reversing the Montana Department of Natural Resources and Conservation's (DNRC's) issuance of a beneficial water use…

The Ninth Circuit affirmed in part and vacated in part a district court's dismissal of a county's complaint in long-standing litigation over appropriation of water in the Walker River…

The U.S. Supreme Court denied, 8-0, Texas' motion to review a river master's final determination in a long-running dispute over how Texas and New Mexico share water. Texas challenged the…

The Fourth Circuit stayed a pipeline company's use of a nationwide permit, verified by the Army Corps of Engineers, to carry out construction of the Mountain Valley Pipeline in streams and…

The Montana Supreme Court affirmed vacatur of a Montana Pollutant Discharge Elimination System (MPDES) permit issued by the Montana Department of Environmental Quality (MDEQ) for a copper and…

A district court denied mine owners' motion to dismiss a lawsuit alleging they were in violation of their NPDES permit. A conservation group and the state of Washington argued that the owners…

A district court vacated EPA's 2019 determination that found no jurisdictional waters under the CWA at a salt production complex bordering the southwestern San Francisco Bay. The Agency…

The Tenth Circuit held, 2-1, that a sovereign must affirmatively act to extinguish aboriginal water rights in a lawsuit concerning water rights of the Pueblos of Jemez, Santa Ana, and Zia in the…

The Illinois Supreme Court dismissed a lawsuit concerning the city of Chicago's replacement of water meters and water main pipes as well as the partial replacement of lead service lines that…

A district court denied a motion to reconsider its 2018 ruling that gave EPA discretion as to how to establish a new TMDL for trash in the Anacostia River. An environmental group argued that…