Special Public Notice
Announcement: Published: December 12, 2025
Maryland Wetland Assessment Methodology
PN-25-47
Baltimore District
This special public notice is to inform the public of the official release of the Maryland Wetland Assessment Methodology, Version 2.0 (MDWAM) for use in the assessment of non-tidal wetlands within the Baltimore District boundaries in the State of Maryland. MDWAM will be a major component in the quantification of unavoidable impacts to non-tidal wetlands and subsequently for the development of compensatory mitigation requirements associated with such impacts in the state of Maryland.
BACKGROUND: Impacts to waters of the United States, including wetlands, are required to be avoided and minimized to the greatest extent practicable as part of the Clean Water Act Section 404 permit application review process. The United States Army Corps of Engineers (Corps) may require compensatory mitigation to offset losses of wetland function resulting from permitted activities (40 CFR 230, 404(b)(1) Guidelines). Mitigation may be accomplished through the restoration, enhancement, establishment, or preservation of aquatic resources (33 CFR 332, 2008 Mitigation Rule). During the Corps evaluation of Department of the Army permit applications, potential individual and cumulative adverse impacts to the aquatic environment are evaluated, with the requirement for compensatory mitigation determined on a case-by-case basis.
The MDWAM was developed, and field tested by the Corps, Baltimore District, Regulatory Branch, in collaboration with the agency partners. The primary objective of MDWAM is to develop a defensible tool to evaluate wetland condition in a rapid and repeatable manner and to increase the consistency of the Corps’ permit decision making process under Section 404 of the Clean Water Act, in the State of Maryland.
MDWAM was developed as a tool to improve understanding of wetland functions and conditions, and to better inform impact avoidance/minimization efforts, evaluate project alternatives, development of project plans, and development and monitoring of compensatory mitigation (here forth referred to as “mitigation”) efforts. MDWAM provides a determination of wetland condition, allowing for distinction between wetland habitats of different type, quality, landscape position, and sensitivity, and will be paramount in promoting the minimization of impacts, avoidance, and potential mitigation planning. MDWAM not only considers the physical extent of wetlands impacted but also changes in the functional and conditional quality as recommended in the Final Mitigation Rule (33 CFR 332, 2008 Mitigation Rule).
The Baltimore District, Regulatory Branch will be using MDWAM during review of projects to provide a consistent and transparent process in determining wetland condition, assessment of impacts to wetland functions, and determining mitigation requirements for unavoidable impacts to waters of the United States.
Project proponents and applicants may use the MDWAM to objectively assess wetland conditions for project planning, alternatives comparison, and impact assessment and avoidance. MDWAM can be used in restoration and mitigation planning and permitting, including development of mitigation requirements, mitigation plans, monitoring protocols to determine wetland mitigation success, and long-term monitoring.
In the future, MDWAM will become a major component of a wetland calculator (under development) to determine compensatory mitigation credit requirements, or wetland credits generated by various activities. The wetland calculator will be combined with the existing Maryland Stream Mitigation Framework (MSMF V.1) as a means for determining combined stream and wetland credit impacts and/or generation of a project.
THE MARYLAND WETLAND ASSESSMENT METHODOLOGY, VERSION 2.0: MDWAM 2.0 includes a guidebook and several appendices providing numerous examples, illustrations and photographs to better inform the user in applying this method.
The Baltimore District has posted MDWAM, Interim Version 2.0. and appendices to our Regulatory webpage (https://www.nab.usace.army.mil/Missions/Regulatory/Mitigation/). The MDWAM, Version 2.0. and associated documents are listed below with a brief description of each item. A hardcopy of this public notice and associated documents is available upon request to email nab-regulatory@usace.army.mil.
MDWAM, Version 2.0 (Final): The MDWAM, Version 2.0. Guidebook provides detailed instruction on the process and application of this methodology.
Appendix A: Example Wetland Class Photos
Appendix B: Example Metric Photos
Appendix C: MDWAM Data Sheets and Final Scoring Sheets
Appendix D: Example Wetland Assessment and Completed Forms
Appendix E: Range of Condition Scores for MDWAM Field Testing
The Baltimore District has provided both virtual and field instructional training regarding the use of MDWAM Interim Versions 1.0 and 1.1. MDWAM, Version 2.0 is the result of public comment, training, and additional field testing by the Baltimore District. Any future updates or revisions will be posted on our website at https://www.nab.usace.army.mil/Missions/Regulatory/Mitigation/.
For specific questions regarding implementation of MDWAM Version 2.0, please contact Mr. Zach Fry by email at zachary.t.fry@usace.army.mil or by phone at 410-962-6080 or Ms. Jacyln Kelleher by email at jaclyn.k.kelleher@usace.army.mil or by phone at 410-820-8629.