Availability of Interim Draft of National Ordinary High Water Mark Field Delineation Manual for Rivers and Streams

The U.S. Army Corps of Engineers (USACE) and EPA (the Agencies) jointly announce the availability of the Interim Draft of the National Ordinary High Water Mark Field Delineation Manual for Rivers and Streams (National OHWM Manual) and its accompanying data sheet. The Interim Draft National OHWM Manual provides draft technical guidance for identifying and delineating the OHWM using a scientifically supported, rapid framework. The Agencies are requesting comments and feedback from the public and practitioners on the Interim Draft of the National OHWM Manual via the public notice linked below. Following the public comment period and additional field testing, comments and feedback received from the public and practitioners will be utilized to further refine the Interim Draft of the National OHWM Manual for clarity, consistency, and technical accuracy. The one-year testing and comment period ends on December 1, 2023. A final version of the National OHWM Manual is anticipated to be published during 2024.

During the period while the OHWM Manual is an interim draft, OHWM identification and/or delineation for official USACE Regulatory purposes should continue in accordance with the applicable OHWM definition in the Federal regulations, Regulatory Guidance Letter 05-05, and any applicable USACE district policies. However, USACE Regulatory staff are encouraged to test the Interim Draft of the National OHWM Manual and provide comments and feedback by emailing usace.ohwm@usace.army.mil.

Link to Public Notice: https://usace.contentdm.oclc.org/utils/getfile/collection/p16021coll15/id/756
Link to Interim Draft of the National OHWM Manual: http://dx.doi.org/10.21079/11681/46102
Link to additional information on the research supporting OHWM identification and delineation: https://www.erdc.usace.army.mil/Media/Fact-Sheets/Fact-Sheet-Article-View/Article/486085/ordinary-high-water-mark-ohwm-research-development-and-training/