Surface Water Quality
2025 Water Quality Regulations Updates Open for Public Comment
RIDEM is proposing to amend existing state Water Quality Regulations to adopt site specific metals criteria for specified segments as allowed in current regulation, clarify turbidity criteria, adopt EPA-recommended human health toxics criteria, change selected segment classifications to reflect already completed permit terminations, include Wild and Scenic Rivers as Special Resource Protection Waters (SRPWs) as already defined in the regulation, adopt two (2) new estuarine segments without changes to applicable criteria to better reflect current shellfish management, non-substantive typographical errors, remove non-regulatory language, and remove incorporated references by adopting the language into regulatory text.
The red line version of the proposed rule making showing all changes can be found here: 2025 Proposed Water Quality Regulation Amendments
All interested parties are invited to request additional information or submit written or oral comments concerning the proposed amendment until September 28, 2025 by contacting the appropriate party at the address listed below:
Jane Sawyers
Department of Environmental Management
Office of Water Resources
235 Promenade Street, 2nd Floor
Providence, RI 02908
A public hearing, in accordance with R.I. Gen. Laws § 42-35-2.5, to consider the proposed amendment shall be held at which time and place all persons interested therein will be heard. This hearing is subject to R.I. Gen. Laws Chapter 42-46, Open Meetings.
Public Hearing Date and Time: September 18, 2025 3:00 - 4:00PM EST
Public Hearing Location: 235 Promenade Street, 2nd Floor, Providence, RI 02908 Room 280 C1/C2
The Office of Water Resources (OWR) implements the state's Water Quality Standards Program. The Water Quality Standards Program is responsible for ensuring compliance with the Federal Clean Water Act (CWA). The purpose of this program is to restore, preserve, and enhance the water quality of Rhode Island waters, to maintain existing uses and to protect the waters from pollutants so that the waters shall, where attainable, be fishable and swimmable, and be available for all designated uses and thus assure protection for the public health welfare, and the environment. These objectives are implemented through the water quality standards which are a fundamental element of the state's Water Quality Regulations. The water quality standards are developed to define water quality goals for state's waters by deciding what their uses will be (designated uses) and by setting criteria necessary to protect those uses. In addition to establishing water quality goals for state waters, surface water quality standards also serve as the regulatory basis for the establishment of water-quality-based-treatment controls and strategies beyond technology-based controls.
The present water quality condition of each waterbody may, or may not, fully support the designated use (swimming, shellfish consumption, aquatic life, etc.). To evaluate the current level of use support attainment of the state's waters, water quality data is collected and compared to the appropriate criteria for each designated use. Historically, the Rhode Island 305(b), State of the State's Waters Report provided information on the quality of all assessed waters in the state relative to their designated uses and the criteria established in the Rhode Island Water Quality Regulations. Any waterbody that is assessed as not meeting its water quality standards (designated uses and criteria) under the 305(b) assessment process, is placed on the 303(d) List of Impaired Waters.
EPA guidance recommends that states integrate their CWA Section 305(b) water quality assessment report and their CWA Section 303(d) impaired waters list into a single document known as the Integrated Water Quality Monitoring and Assessment Report (Integrated Report) which includes a five-part integrated list format for reporting the water quality assessment status of the state's waters. As part of this new reporting format, states are required to document the assessment and listing methodology utilized to assess the waters of the state for development of the integrated list of waterbodies. The methods the Department uses to develop the Integrated Reports are described in the Consolidated Assessment and Listing Methodology (RI CALM). This document includes a description of the quality assurance requirements, methods used to evaluate water quality data and assess water quality standards attainment, and the rationale for the placement of waterbodies into the integrated list.
For information on the surface water quality condition of a particular waterbody in the state, please contact DEM.WaterResources@dem.ri.gov or (401) 222-3961.
- Water Quality Regulations (250-RICR-150-05-1)
- Stormwater Design and Installation Standards Manual (amended 2015)
- Response to Comments for WQ Reg Amendments (May 2009)
- Supplemental Documentation for WQ Reg Amendments (May 2009)
- Final 2016 Integrated Water Quality List
- Guide to Understanding Freshwater Aquatic Plants
- Identification and Management of Aquatic Invasive Species
- Aquatic Invasive Species Map and List
- Stop Invasive Species Boat Ramp Sign