A water rule that turns a blind eye to transboundary pollution
Debates about the decentralization of environmental policy are important and are far from resolved (1, 2). Interregional spillovers provide one key justification for centralized regulation: When regulation is decentralized, individual jurisdictions may not protect downstream or downwind neighbors from their pollution (2, 3). Under the Trump administration, the U.S. Environmental Protection Agency (EPA) and U.S. Army Corps of Engineers (ACE) departed from precedent to support the deregulation of U.S. waterways in the repeal of the 2015 Clean Water Rule (CWR) and its replacement with the 2020 Navigable Waters Protection Rule (NWPR). In doing so, they assumed (with little evidence) that many states would fill gaps in federal oversight. With the Biden administration having signaled its intent to modernize regulatory review and to review specific deregulatory actions taken by the Trump administration, we describe here how this environmental federalism approach downplays the importance of cross-state pollution and relies on flawed methods of benefit-cost analysis that could be used to weaken other statutes.