On July 26, 2022, the Los Angeles Regional Water Quality Control Board released a draft stormwater permit that would regulate waste discharges from commercial, industrial, and institutional (CII) facilities in the Dominguez Channel/Inner and Outer Los Angeles and Long Beach Harbor Watershed and the Los Cerritos Channel/Alamitos Bay Watershed. After a public comment period, on November 2, 2023, the Water Board responded to comments and released an updated draft CII permit. On March 11, 2024, the Water Board postponed a public hearing on the CII permit until the U.S. Environmental Protection Agency (EPA) takes regulatory action to designate CII sites for permitting under the Clean Water Act.
The CII permit would expand the sites regulated for stormwater discharges in these watersheds, including shopping centers, parking lots, business centers, and other commercial centers. CII sites should stay up to date on the progress of this draft CII permit and prepare for compliance as soon as the Water Board and the EPA finalize regulatory action to adopt it.
Facilities Subject to the CII Permit
The CII permit covers privately owned CII sites with five or more acres of impervious cover, excluding airports. It also covers the unpermitted portions of CII sites whose remaining portions are already subject to another National Pollutant Discharge Elimination System (NPDES) program permit—such sites would be subject to two NPDES permits. Whether a particular site is a “CII site” depends on the Los Angeles County Office of the Assessor’s property use classification code.
Regulation Under the CII Permit
The CII permit authorizes certain non-stormwater discharges (NSWDs) and stormwater discharges subject to technology-based and water-quality-based effluent limitations.
The technology-based effluent limitations require CII sites to develop best management practices (BMPs) that comply with the best conventional pollutant control technology and the best available technology economically achievable to reduce or prevent discharges of pollutants in their stormwater discharge. CII sites must put these BMPs into a site-specific stormwater pollution prevention plan (SWPPP) to ensure compliance.
The water-quality-based effluent limitations require CII sites to choose one of three compliance options:
- Agreement with Local Watershed Management Group to Fund Regional Project. The CII site enters into a legally binding agreement with a local watershed management group to fund, or partially fund, a regional project.
- Facility-Specific Design Standard to Reduce Stormwater Runoff. The CII site designs, implements, and maintains stormwater controls that have the effective capacity to capture and use, infiltrate, and/or evapotranspire all NSWDs and the volume of runoff produced up to and during an 85th percentile 24-hour storm event.
- Direct Demonstration of Compliance with Water Quality Based Effluent Limitations. The CII site demonstrates through sampling and analysis that discharges of stormwater meet effluent limitations identified in tables 1 through 4 of the CII permit.
Timing of the CII Permit
Generally, CII sites should be prepared to submit notices of intent and SWPPPs within one year of the effective date of the CII permit and choose their compliance option within two years of the effective date. CII sites that are considered “new dischargers,” however, must submit these documents at least 45 days before their first authorized discharge.
Takeaway
The CII permit would regulate far more sites and facilities in Los Angeles and Long Beach than are regulated under existing NPDES permits, with the Water Board estimating 640 new dischargers eligible to apply for coverage.
CII sites should review the CII permit and stay engaged with the latest developments as the Water Board and the EPA move towards finalizing it, including looking for opportunities to participate through comments or a hearing. CII sites should also prepare for compliance as soon as the Water Board and the EPA finalize and adopt the CII permit. CII sites should carefully review each compliance option, and its opportunities and challenges, to determine which compliance option best fits the unique conditions at their site.