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Waters of the United States (WOTUS) Rulemaking

Proposed Revised Definition of WOTUS - Supporting Documents

On December 11, 2018, the EPA and Department of the Army signed a proposed rule revising the definition of "waters of the United States" to clarify federal authority under the Clean Water Act in a clear and understandable way. The proposed definition would replace the approach in the 2015 Rule and the pre-2015 regulations.

The agencies are providing both an Economic Analysis and a Resource and Programmatic Assessment as supporting documents to the proposed rule. The Economic Analysis (EA) assesses the potential impacts of the proposed changes to the definition of “waters of the United States” based on the potential effects to CWA programs that rely on the definition of “waters of the United States.” The Resource and Programmatic Assessment outlines the agencies’ assessment of the potential effects of the proposed definition on CWA programs and certain programs addressing aquatic resource quality under other federal statutes. The Resource and Programmatic Assessment also provides snapshots of the applicable regulatory and legislative frameworks in place in states and tribes. The two documents together present a comprehensive assessment of this rule’s potential impacts.

The agencies will take comment on the proposed rule for 60 days after publication in the Federal Register. The proposed rule and supporting documents are identified by Docket No. EPA-HQ-OW-2018-0149.

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