2024 Western Washington stormwater permit changes

With the current 2019 permit set to expire this July, the Washington State Department of Ecology is in the process of transitioning to the 2024 Phase II Municipal Stormwater Permit. This updated permit enhances the framework for managing stormwater runoff and adhering to the Clean Water Act's directives. The revisions reflect a nuanced approach to water quality protection, emphasizing community involvement, expanded program components, and introducing new practices like detailed MS4 mapping and comprehensive street sweeping requirements. Let's explore these updates and their implications for sustainable stormwater management.

MS4 Mapping with Pipe Size and Material

Previously Required: The 2019 permit required municipalities to map their MS4 systems but did not explicitly require detailed information on pipe size and material for outfalls.

Now Required: The 2024 permit mandates that municipalities include specific details in their MS4 mapping, such as the precise geolocation, pipe size, and material of all known MS4 outfalls. This additional detail aids in more effective infrastructure management and maintenance planning.

Illicit Discharge Detection and Elimination (IDDE) Protocols

Previously Required: The 2019 permit required municipalities to establish IDDE programs but may have been less prescriptive about the specific components of these programs.

Now Required: The 2024 permit specifies a more structured IDDE program, including systematic inspections, establishing a public reporting system like a hotline, and detailed staff training on identifying and managing illicit discharges. This ensures a more proactive and community-involved approach to eliminating pollution sources.

Record Keeping and Public Access

Previously Required: Municipalities were required to maintain records related to the permit and SWMP activities but with less emphasis on public accessibility.

Now Required: The 2024 permit emphasizes not only detailed record-keeping of all stormwater management activities for at least five years but also mandates that these records be readily accessible to the public upon request, enhancing transparency and community trust.

Annual Reporting with SWMP Implementation Details

Previously Required: Annual reporting was necessary under the 2019 permit, focusing on compliance and general summaries of stormwater management activities.

Now Required: The 2024 permit requires more comprehensive annual reporting that details SWMP implementation, effectiveness evaluations, expansions of permit coverage areas, and specific updates or improvements in stormwater management practices. This expanded reporting ensures ongoing evaluation and public accountability of stormwater management efforts.

Community-Based Social Marketing for Public Education

Previously Required: Public education efforts were required under the 2019 permit, emphasizing general awareness and information dissemination.

Now Required: The 2024 permit calls for the use of community-based social marketing techniques for public education campaigns, focusing on specific behavior changes related to stormwater management. This involves identifying community-specific barriers and benefits to change, thereby creating more targeted and effective educational initiatives.

Street Sweeping Program Specifications

Previously Required: While street sweeping was recognized as a good management practice, specific program requirements or schedules were not as explicitly mandated.

Now Required: The 2024 permit requires municipalities to implement a formalized street sweeping schedule, particularly targeting areas with higher pollutant loads. This proactive approach aims to significantly reduce the amount of pollutants entering the MS4 from roadways, emphasizing the importance of street cleanliness in overall stormwater quality.

In summary, the revised permit introduces important updates, including detailed MS4 mapping, increased illicit discharge detection protocols, improved record-keeping for public requests, new annual reporting requirements, community-based public education efforts, and formalized street sweeping programs. NPDESPro is here to support phase II MS4s through these changes, ensuring effective permit management and a smooth transition.

If you have questions regarding how NPDESPro can help you streamline NPDES permit requirements, please contact us here.

*Please note that permit updates are still under review and are subject to change.