On December 1, 2022, the Environmental Protection Agency issued an Administrator’s Determination under the Clean Water Act that revised water quality standards in certain zones of the Delaware River are necessary to meet the requirements of the Act. Specifically, the EPA determined that a designated use that includes propagation and corresponding protective dissolved oxygen criteria are required to protect sensitive aquatic life – including two federally listed species under the Endangered Species Act – in zones 3, 4, and upper-5 of the Delaware River. On December 13, 2023, the EPA Administrator signed a proposed rule. The EPA is now fulfilling its statutory obligation to promulgate final protective water quality standards for certain zones of the Delaware River.