2024 Updates: Residual Designation Authority (RDA) Activities Underway for the Charles, Neponset, and Mystic River Watersheds

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August/September 2024

Permit Update

EPA, Region 1 continues to work on finalizing the draft Residual Designation Authority (RDA) permit, and other associated permitting documents, and is on track to publish the draft permit later this fall. EPA will be seeking comments on both the Draft Residual Designation Permit as well as the Preliminary Residual Designation Authority determination which identified for permitting certain commercial, industrial and institutional parcels with one acre or more of impervious cover in the Charles, Mystic and Neponset River Watersheds. The public comment period, which will last 90 days, will be announced in the Federal Register and also on EPA’s website. EPA will also provide notice of public meetings and public hearings on the draft permit and preliminary determination.

EPA has updated technical information sheets for each municipality in the Charles River watershed. These information sheets contain updated parcel-level data for the Charles River Watershed.

EPA is also releasing the updated parcel-level data report (pdf) (3.5 MB) for the Charles River Watershed. This updated parcel level report relies on a more recent analysis of the parcel data in the watershed and is consistent in approach to that of the Mystic and Neponset River Watersheds.

Stakeholder Engagement

EPA has engaged in extensive outreach on this permitting matter; for further information, please go to EPA's website which includes a recently-released report (pdf) (465 KB) that identified issues of concern, as well as suggestions for how to address certain permitting challenges.

As part of the public comment period mentioned above, EPA will be hosting a series of public meetings and public hearings early in 2025 to answer questions, and also to get feedback, on this permitting matter.

If you have questions, please contact EPA at: [email protected].

July 2024

Permit Update

EPA continues to develop the draft permit and related documents. If you have thoughts or questions on the development of the permit contact EPA at [email protected].

EPA continues to update the parcel-level datasets for the Charles River Watershed. Where relevant, updated municipal-specific information fact sheets will be available at the end of summer.

Stakeholder Outreach and Tools

EPA published a 2-page information sheet (pdf) (669 KB) in June that explains stormwater pollution, EPA's residual designation authority, and the potential impacts this permit may have on communities in general terms. This information sheet has been translated into relevant languages and translations are now available.

Lastly, CBI facilitated five virtual focus groups to identify challenges and brainstorm solutions for the RDA permit. The focus groups occurred in June 2024. In the focus group sessions, EPA sought feedback on a set of permit implementation topics as outlined in these questions. The five focus groups were supported by: (1) 495 Partnership, (2) Colleges, universities, and hospitals, (3) municipalities, (4) NAIOP, (5) watershed associations. Focus groups discussed permit phasing, redevelopment, offsite mitigation, minimizing pollutant reduction, and the overlap between the MS4 and RDA permits. EPA was not seeking agreement or consensus from focus group participants, but rather informed input from individual focus group participants. CBI prepared a summary report (pdf) (465 KB) that captures the range of views and opinions expressed and should in no way be seen as generating a singular approach, path, or recommendation, but a diverse set of views, advice, and ideas.

June 2024

Permit Update

EPA continues to develop the draft permit and related documents. If you have thoughts or questions on the development of the permit contact EPA at [email protected].

EPA is currently updating the parcel-level datasets for the Charles River Watershed. Where relevant, updated municipal-specific information fact sheets will be available at the end of summer.

Stakeholder Outreach and Tools

EPA has developed a 2-page information sheet (pdf) (669 KB) that explains stormwater pollution, EPA’s residual designation authority, and the potential impacts this permit may have on communities in general terms. This information sheet will be translated into relevant languages and the translations will be made on our website soon.

EPA convened a series of focus groups in June to hear feedback from individuals on RDA permit implementation topics including permit phasing and the timing of compliance deadlines, off-site mitigation opportunities and challenges, regionalized approaches to stormwater management, how to address new development on RDA sites as well as other issues that were raised by participants. A report summarizing those discussions will be available on the EPA website soon.

As part of the technical assistance that EPA held with the three communities (Milford, Stoughton, and Somerville) in the Charles, Mystic, and Neponset River Watersheds, CBI and the UNH Stormwater Center in 2024, the final UNHSC Performance Curve and O&M Tracking Calculator (xlsm) (2.7 MB) is now available, where municipalities are able to not only track SCM performance, but also log and estimate hours needed to perform O&M.

May 2024

Permit Update

EPA continues to develop the draft permit and other permit documents and to seek feedback on a variety of permit implementation questions. If you have thoughts on these questions (pdf) (96 KB), or any other permit issues, feel free to email EPA at [email protected].

EPA is currently updating the parcel-level datasets for the Charles River Watershed. Where relevant, updated parcel sets as well as updated municipal-specific information fact sheets will be available at the end of summer.

Stakeholder Outreach

Recent and upcoming presentations include:

Stormwater Technical Assistance

EPA completed its stormwater technical assistance series with the municipalities of Milford, Somerville, and Stoughton in May. The main themes that emerged as part of this series were focused on streamlining maintenance requirements of existing structural stormwater controls to ensure proper operations and efficient ways to estimate the cost or time required for this maintenance. The University of New Hampshire Stormwater Center updated its SCM Performance Calculator (updated version available soon), which quantifies water quality performance using the MS4 permit performance curves and now includes person hour estimates for maintenance of stormwater controls.

Another theme that was important to the participating municipalities was to learn about a successful self-certification program for maintenance of privately owned structural controls. EPA invited the City of Lowell to provide an overview of setting up and managing their self-certification program for privately owned stormwater controls.

April 2024

Permit Update

EPA continues to make presentations to stakeholders to provide background information on the regulatory and technical basis for the RDA permit and opportunities for future stakeholder involvement, including ways to provide feedback on solutions to permit implementation challenges. To conduct this stakeholder outreach, the RDA team is again working with the Consensus Building Institute, which was involved in the initial stages of RDA stakeholder outreach which began in 2020.

The RDA team met with the Long Creek Watershed Management District which is implementing the Long Creek RDA permit in Maine. The LCWD’s website https://www.restorelongcreek.org outlines the steps the organization has taken in advancing stormwater management in the watershed.

Recent and upcoming presentations include:

Technical Assistance and Tools

In March 2024 EPA posted a RDA Permit Frequently Asked Questions (pdf) (185 KB) document that answers questions it has been receiving about this new RDA permitting program from stakeholders.

In its ongoing technical assistance designed to look at streamlined operations and management of stormwater controls on April 23, 2024, EPA met with municipal officials from Milford, Stoughton, and Somerville for the fourth of five meetings. At this meeting municipalities heard about a self-certification program that the City of Lowell has developed to track regular maintenance of stormwater controls on private properties. The group workshopped through a set of questions to evaluate how this kind of program could be implemented in their municipalities in breakout rooms. The fifth and final meeting will be hosted at EPA office in Boston where municipalities will report out on their final project deliverables that were developed in partnership with the UNH Stormwater Center.

March 2024

Permit Update

EPA continues to work on developing the draft RDA permit. EPA is currently seeking feedback on permit implementation strategies such as whether the permit should be phased, BMP implementation challenges (types, siting challenges, timing of requirements), overlaps with other local, state and federal regulatory programs, the impact to funding mechanisms such as stormwater utilities, and a variety of other issues (as highlighted in the posted presentations on the EPA website). If you have ideas on these permit strategies that you want to share with EPA, please contact [email protected].

Stakeholder Outreach

EPA continues to reach out to stakeholders to provide background information on the regulatory and technical basis for the RDA permit. To conduct this stakeholder outreach, the RDA team is again working with the Consensus Building Institute, which was involved in the initial stages of RDA stakeholder outreach which began in 2020.

Recent presentations include:

EPA is now developing the next phase of its outreach plan and is seeking feedback on specific questions related to permit implementation. If you have ideas that you want to share with EPA, please contact [email protected].

Technical Assistance and Tools

EPA has posted a RDA Permit Frequently Asked Questions (pdf) (185 KB) document that answers questions it has been receiving about this new RDA permitting program from stakeholders. EPA will update this document regularly as new relevant questions arise.

In its ongoing technical assistance designed to look at streamlined operations and management of stormwater controls on March 12, 2024, EPA met with municipal officials from Milford, Stoughton, and Somerville for the third of five meetings. At this meeting municipalities shared updates from one-on-one sit visits with the UNH Stormwater Center and set goals for what specific needs each community has that is being addressed as part of this project. The group is reconvening for a fourth group meeting in April where a guest speaker will describe a successful self-certification program for private stormwater controls.

February 2024

Release of Technical Documents

As EPA announced in its January Update, the technical parcel-level analyses are now available for each watershed: Charles River (pdf) (1.6 MB), Mystic River (pdf) (5 MB) and Neponset River (pdf) (5.1 MB).

Stakeholder Outreach

EPA continues to make presentations to stakeholders to provide background information on the regulatory and technical basis for the RDA permit and opportunities for future stakeholder involvement, including ways to provide feedback on solutions to permit implementation challenges. To conduct this stakeholder outreach, the RDA team is again working with the Consensus Building Institute, which was involved in the initial stages of RDA stakeholder outreach which began in 2020.

Recent and upcoming presentations include:

  • MA Rivers Alliance RDA Presentation (pdf) (2.6 MB): Feb 28th 2024, 10-11:30 am
  • Charles River Watershed Association RDA Presentation: March 7th 2024, 1-2 pm
  • Mystic River Watershed Association RDA Presentation: March 14th 2024, 9-10:30 am
  • NAIOP/495 Partnership RDA Presentation: March 22nd 2024, 9-10:30 am
  • Association of Independent Colleges and Universities Massachusetts and Massachusetts Health and Hospital Association RDA Presentation: April 1st 2024, 10-12 am
  • Metropolitan Area Planning Council RDA Presentation: TBD

Technical Assistance and Tools

EPA has compiled Municipal-Specific Technical Informational Fact Sheets for each community in all three watersheds that provide more information about the upcoming RDA permits. These fact sheets include information about the land use types expected to receive RDA permits and the estimated amount of phosphorus pollution coming from each municipality by those land use types (which include certain commercial, industrial, and institutional entities). Examine a complete list of the Municipal-Specific Technical Informational Fact Sheets.

EPA continues to work with the University of New Hampshire (UNH) Stormwater Center to offer technical assistance to three municipalities focused on improving operation and maintenance of stormwater control measures as well as innovative tracking and accounting solutions in municipal stormwater management. This work is happening with three communities in the watersheds who responded to a solicitation and who have environmental justice concerns.

On February 12, 2024, EPA met with municipal officials from Milford, Stoughton, and Somerville for the second of five meetings. At this meeting municipalities honed their needs for specific technical assistance needs, which all focus on streamlining operations and maintenance programs. The municipalities will meet with the UNH Stormwater Center next to start to develop tools to support each program's specific needs and reconvene for a third group meeting in March. The work in these communities will also serve as a model for other communities with similar stormwater challenges in Massachusetts.

Questions on RDA Permitting

Contact: [email protected]

January 2024

Release of Technical Documents

The technical parcel-level analysis for the Mystic and Neponset River Watersheds have been posted on EPA's website. You can find the watershed-specific documents at:

EPA has already released the background technical parcel-level report for the Charles River Watershed when it made its Preliminary Designation; that information can be found at the link above, or in Attachment 6 of the Preliminary Designation (pdf) (7 MB). In all of these reports, EPA summarizes the types and numbers of parcels with one or more acres of impervious surface that contribute stormwater pollution within these watersheds.

EPA plans to conduct further outreach in the future to allow users to better understand the amount of stormwater run-off coming from various land use types within municipal boundaries in the three watersheds.

Stakeholder Outreach

On January 17th, 2024, EPA kicked off the stakeholder outreach process for the MA RDA permit with a presentation at a virtual meeting hosted by the Neponset River Watershed Association. The Neponset Presentation (pdf) (1.7 MB) included background information on the regulatory and technical basis for the RDA permit and identified opportunities for future stakeholder involvement, including ways to provide feedback on solutions to permit implementation challenges. The RDA team is again working with the Consensus Building Institute, which was involved in the initial stages of RDA stakeholder outreach which began in 2020.

EPA will be attending the Mystic River Watershed Association and the Charles River Watershed Association to discuss the RDA permitting effort in upcoming weeks (February – March).

Technical Assistance

EPA is working with the University of New Hampshire (UNH) Stormwater Center to offer technical assistance focused on improving operation and maintenance of stormwater control measures as well as innovative tracking and accounting solutions in municipal stormwater management. This work is happening with three communities in the watersheds who responded to a solicitation and who have environmental justice concerns. On January 8th, 2024, EPA held the kickoff meeting in Milford, MA with municipal officials from Milford, Stoughton, and Somerville along with representatives of the Charles, Mystic, and Neponset River Watershed Associations. The project will run through May 2024 and help develop solutions to each community's' unique stormwater challenges, with technical support from the UNH stormwater center. The work in these communities will also serve as a model for other communities with similar stormwater challenges in Massachusetts.

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Last updated on January 16, 2025