This podcast episode addresses recent US Supreme Court decisions and ongoing litigation before the Court regarding the interaction of surface water and groundwater. Three recent United States Supreme Court cases — the decisions in County of Maui v. Hawai’i Wildlife Fund and Mississippi v. Tennessee, and the ongoing litigation before the Supreme Court in Texas v. New Mexico and Colorado — reflect the slow but inevitable changes to the traditional legal framework surrounding federal consideration of surface water and groundwater interaction. Our guest is Kathy Robb, the author of an article discussing these cases and related issues.