A new year heralds potential changes in stormwater regulations. Let’s delve into the latest updates with insights from our stormwater experts.
EPA expands stormwater regulation in Los Angeles and Boston watersheds
The Los Angeles Regional Water Board and EPA are considering potential regulatory requirements for stormwater runoff from certain commercial, industrial, and institutional facilities in two Los Angeles watersheds and three Boston watersheds, to reduce pollutant levels in stormwater runoff. Companies operating in these regulated industries may need to obtain or update their existing stormwater permits under the National Pollutant Discharge Elimination System (NPDES).
Why it matters: Private sector clients within these watersheds will need to comply with stricter stormwater regulations. Many of these will be new to stormwater permitting and compliance, such as shopping centers, hotels, supermarkets, hospitals, and churches.
Municipalities, currently under stringent Total Maximum Daily Load (TMDL) requirements, will see a shift in regulatory burden toward private entities. Despite an uncertain timeline, the overall impact is expected to be positive, reducing the municipalities’ regulatory load. This approach may serve as a model for other watersheds with TMDL requirements, especially if these regulations are adopted in other watersheds.
Draft Multi-Sector General Permit for industrial stormwater discharges proposed
To replace the 2021 Multi-Sector General Permit (MSGP), the EPA is seeking public comment on a proposed 2026 MSGP for stormwater discharges from industrial activities in geographies where the agency is the permitting authority. Comments must be received on or before Feb. 11, 2025. An EPA webinar is scheduled for Jan. 16, 2025.
Why it matters: The proposed draft permit includes significant changes relative to the 2021 MSGP, including PFAS indicator monitoring, 2021 indicator parameters shifting to benchmark parameters for some sectors, changes in benchmark and impaired waters monitoring frequency, and Additional Implementation Measures reports.
Questions? Reach out to Environmental Engineer Stephanie Alimena or Water Resources Regional Practice Lead Laura Carpenter.
About the Expert
Liz Wilson is Compliance and Permitting National Practice Leader for Brown and Caldwell. She is based in New Hampshire and has 20 years of environmental consulting and industry experience.
National Regulatory Dates
Jan. 1
GHG Reporting Rule Amendments for the Petroleum and Natural Gas Systems Category effective date
Jan. 22
Integrating e-manifest with hazardous waste exports
Feb. 11
Proposed 2026 Multi-Sector General Permit public comments due
March 1
Tier II Reporting deadline