Maryland’s 2019 Triennial Review of Water Quality Standards

Maryland's 2019 Triennial Review of Water Quality Standards

On September 12, 2022, the Secretary of the Environment adopted amendments to the water quality standards regulations. Final action on the regulations was published in the October 21, 2022 edition of the Maryland Register Online and became effective on October 31, 2022. MDE is currently finalizing Maryland’s Triennial Review of Water Quality Standards package for EPA’s approval.

For the public review process, MDE published a notice of proposed action in the March 11, 2022 issue of the Maryland Register. This marked the beginning of the public comment period that ended on April 11, 2022. During this public comment period MDE also held a virtual public hearing on March 30, 2022.

Please click on the links below to access the materials associated with the 2019 Triennial Review including the description of regulatory changes, the recording of the public hearing and presentation, the comment-response document, and the letter of approval from EPA.

Triennial Review of Water Quality Standards and the Regulation Changes Made

The document immediately below provides the specific regulatory language that was revised in the Code of Maryland Regulations and a summary of what water quality standards were reviewed.

Maryland’s 2019 Triennial Review of Water Quality Standards

The following documents were incorporated by reference into the Code of Maryland Regulations (COMAR) as part of this Triennial Review. As adopted, they have the same authority and weight as regulatory language captured in COMAR.

Procedures for Applying the Mussel-Absent Ammonia Criteria to Maryland Surface Waters (Maryland Department of the Environment, May 7, 2021): Incorporated by reference in COMAR 26.08.02.03-2H(1) and COMAR 26.08.02.03-2I(3)
Ambient Water Quality Criteria for Dissolved Oxygen, Water Clarity and Chlorophyll a for the Chesapeake Bay and Its Tidal Tributaries--2017 Technical Addendum (EPA 903-R-17-002), Chapter II and III: Incorporated by reference in COMAR 26.08.02.03-3C(8)(g)
Cold Water Existing Use Determinations: Policy and Procedures (Maryland Department of the Environment, May 12, 2021): Incorporated by reference in COMAR 26.08.02.04-1C.

Materials from the Public Hearing on March 30, 2022

Supporting Materials for this Triennial Review

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 reclassified to 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 use classification changes where applicable.