On 3 October 2022, the US Supreme Court heard arguments in Sackett v. USEPA, the latest in a series of cases seeking to clarify which waters are protected under the US Clean Water Act (1). Concurrently, the US Environmental Protection Agency (EPA) and the US Army Corps of Engineers are actively drafting rules for the third time in the past 10 years, after the Obama-era Clean Water Rule (2) was repealed (3) and the Trump-era Navigable Waters Protection Rule (4) was vacated and remanded (5). Consequently, enforcement of the Clean Water Act has reverted to 1986 agency guidance (6). Although scientific understanding of the physical, chemical, and biological connectivity of waters (7) and the ability to leverage geospatial data to guide jurisdictional determinations (8, 9) have grown substantially since 1986, the Clean Water Act enforcement and rulemaking have yet to catch up.
