On June 1, 2020, the US Environmental Protection Agency (“EPA”) announced a final rule narrowing the ability of states and Indian tribes to formally object to federally permitted projects based on state water quality standards. Under Section 401 of the Clean Water Act, states—and authorized tribes—are given the opportunity to review certain proposed projects requiring federal permits to determine whether those projects will comply with applicable water quality standards. States had been increasingly using the so-called Section 401 certification process to block or significantly delay certain development projects. EPA’s new rule will make it more difficult for states and authorized tribes to deny or condition Section 401 certifications.