This chapter first explains how the federal Clean Water Act is linked with the implementation of other major environmental laws in the United States. That is, while the Clean Water Act serves an overarching goal "to restore and maintain the chemical, physical, and biological integrity of the Nation's waters," it often does much more than that. Since its enactment in 1972, the Clean Water Act has consistently—and positively—helped to vindicate other public interest values that are not obviously connected to water quality, such as the preservation of historic resources or ensuring environmental justice. Critically, the protection of these non-water quality benefits occurs by congressional design. Issuance of a Clean Water Act permit often triggers other necessary reviews under the National Environmental Policy Act, the National Historic Preservation Act, and the Endangered Species Act, among other laws. We refer to this regulatory interplay as the Clean Water Act's 'ripple effect.'

This chapter's second contribution is to document how holistic environmental reviews engendered by the 'ripple effect' are now at risk, as the Supreme Court of the United States reconsiders the jurisdictional reach of the Clean Water Act. With Sackett v. Environmental Protection Agency, the Court is reassessing the question of which aquatic resources are covered as "waters of the United States." A new line "at which water ends and land begins" is being drawn. Historically, the Clean Water Act has safeguarded wetlands, marshes, streams, and tributaries that have a "significant nexus" to a navigable waterway. But if wetlands or tributaries are found to be outside of the Clean Water Act's purview pursuant to a new ruling in Sackett, then the 'ripple effect' never occurs. The impact here may be profound. The interconnectivity of the Clean Water Act with other federal statutes, after all, reflects the interconnectedness of the resources these laws seek to protect.

Cale Jaffe & Aspen Ono, Ripple Effect: A Look at Sackett v. EPA and the Non‐Water Quality Values that the Clean Water Act Protects, in Environmental Law Before the Courts: A US-EU Narrative, Springer Nature (2023).