A new stormwater permit program from the Environmental Protection Agency (EPA) will regulate stormwater runoff from some private parcels in eastern Massachusetts and may impact you. The Residual Designation Authority (RDA) permit, anticipated for draft issuance this fall, will target private parcels that exceed one acre of impervious surface within the Charles River, Neponset River, and Mystic River watersheds.
The intent of this regulatory action is to enhance the water quality within these critical watersheds by mitigating the levels of pollutants present in stormwater runoff. While the EPA has conducted preliminary information sessions on the permit, the final requirements of the permit remain under deliberation and are expected to be released in the near future. It is anticipated, however, that the permit will require the owner’s construction of both structural and non-structural stormwater controls for existing impervious surfaces, even if no other site improvements are proposed. Improvements may include:
- Non-structural controls may include measures such as street, driveway, and parking lot sweeping; catch basin cleaning; and erosion control measures. These efforts would require landowners to implement Operation and Maintenance Plans to clean and maintain their sites on an annual basis.
- Structural controls may include retrofitting a site to construct a stormwater management system that provides treatment to runoff. These efforts would require landowners to construct best management practices to remove pollutants such as proprietary stormwater treatment structures, infiltration basins, biofiltration, and rain gardens.
Nitch Engineering is supporting clients like you to gain a greater understanding your specific potential impacts of the pending permit and what your potential requirements may be. For a comprehensive understanding of how this permit may increase your responsibilities and to stay abreast of the latest developments, we invite you to reach out to Deborah Danik, PE, LEED AP BD+C or Brian Creamer, AICP, SITES AP.