Maryland's 2025 Triennial Review of Water Quality Standards
Maryland Department of the Environment will be proposing changes to Maryland's Water Quality Standards as part of the 2025 Triennial Review of Water Quality Standards cycle. Please click on the links below to access the materials associated with the 2025 Triennial Review, including the description of the proposed regulatory changes and supporting documents.
Public Review & Comment
Advanced Public Notice of Rulemaking (ANPRM) for the 2025 Triennial Review of Water Quality Standards was provided September 14, 2024, and updated January 24, 2025. The ANPRM notification provides an early opportunity for public comment on the topics the Department is considering in the next Triennial Review. To access the ANPRM notice, please
click here.
The Department plans to publish a notice of proposed action in the October 16th, 2026 issue of the
Maryland Register.
The public comment period for this action will be open from October 16, 2026 to November 18, 2026. Written comments can be sent either via email to Ms. Melinda Cutler at [email protected] or via mail at the following address:
Ms Melinda Cutler
Watershed Protection, Restoration, and Planning Program
Maryland Department of the Environment
1800 Washington Boulevard
Baltimore, MD 21230-1720
A hybrid public hearing will be held on October 29, 2026 from 5:30 p.m. - 7:30 p.m. The public hearing will be hosted virtually on the Google Meets platform and in-person at the Catonsville Public Library (1100 Frederick Rd, Catonsville, MD 21228). The Maryland Department of the Environment will present the proposed changes to Maryland's water quality standards in the Code of Maryland Regulations and accept public comments.
The agenda for the public hearing is posted here. To register for the public hearing, please fill out the registration form, linked here.
Triennial Review of Water Quality Standards and the Proposed Regulation Changes
The document below provides the specific regulatory language that is proposed for revision in the Code of Maryland Regulations (COMAR) and a summary of what water quality standards were reviewed.
The following document was updated and will be re-incorporated by reference into the Code of Maryland Regulations (COMAR) as part of this Triennial Review proposal. As adopted, incorporated by reference documents have the same authority and weight as regulatory language captured in COMAR.
Supporting Materials
The following documents were not incorporated by reference but provide supporting information, justification and context for the amendments to Maryland’s water quality standards.
Designated and Existing Uses
Recent data have shown that the current use classification of some Maryland surface waters are not protective of their existing use. The existing uses of these streams have been formally recognized by the Department and some surface waters were identified as synonymous as Use Class III (or III-P) where data has demonstrated that the designated use and criteria are being attained. The following documents provide justification for and describe the scale of existing use determinations and proposed use classification changes where applicable.
Antidegradation Policy
New biological data have identified several new High Quality Tier II streams. The following document provides information on these new Tier II streams and justification for the proposed changes.
Contact Information
For more information, please contact Melinda Cutler at [email protected].
This page was last updated on 08/2026
