California Code of Regulations › Title 23 - Waters › Division 4 - Regional Water Quality Control Boards › Chapter 1 - Water Quality Control Plans, Policies, and Guidelines › Article 4 - Los Angeles Region › Section 3939.60 - Basin Plan Amendment to Incorporate a Total Maximum Daily Load for Indicator Bacteria in Los Cerritos Channel and Estuary, Alamitos Bay, and Colorado Lagoon

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
On March 10, 2022, the Los Angeles Regional Water Quality
					 Control Board (Los Angeles Water Board) adopted Resolution No. R22-002,
					 amending the Water Quality Control Plan for the Los Angeles Region (Basin Plan)
					 to incorporate a total maximum daily load (TMDL) for indicator bacteria in Los
					 Cerritos Channel and Estuary, Alamitos Bay, and Colorado Lagoon. The State
					 Water Resources Control Board (State Water Board) approved the amendment under
					 Resolution No. 2022-0053 on December 6, 2022.
The TMDL sets numeric targets for indicator bacteria based
					 on numeric water quality objectives provided in the Basin Plan and Statewide
					 Bacteria Provisions. The TMDL assigns waste load allocations (WLAs) to
					 municipal separate storm sewer system (MS4) discharges and other non-MS4
					 National Pollutant Discharge Elimination System (NPDES) discharges, and load
					 allocations (LAs) to nonpoint source discharges to attain water quality
					 objectives for bacteria. The water quality objectives are set to protect public
					 health based on the water contact recreation (REC-1) beneficial uses of these
					 waterbodies and will also result in the protection of the non-contact water
					 recreation (REC-2) beneficial use.
There are two types of numeric targets: geometric mean
					 limits calculated over the period of six weeks and a corresponding statistical
					 threshold value (STV) calculated over the period of a calendar month. The
					 applicable STV shall not be exceeded in more than 10 percent of the samples
					 collected in a calendar month, calculated in a static manner. Exceedances of
					 the objectives are frequent during all seasons and conditions and recreational
					 uses of the Los Cerritos Channel and Estuary, Alamitos Bay, and Colorado Lagoon
					 take place during all seasons and conditions, therefore the TMDL allocations
					 are applied equally during all time periods and conditions. No exceedance days
					 of the geometric mean targets are allowed at any time. However, if it is not
					 possible to calculate a geometric mean due to lack of sufficient data, then
					 attainment of the numeric targets shall be determined based on the STV.
The TMDL requires the MS4 dischargers to achieve the final
					 WLAs within 15 years. Other non-MS4 point source dischargers (such as other
					 individual NPDES permittees and general NPDES permittees, including industrial
					 stormwater permittees and construction stormwater permittees) must achieve WLAs
					 upon the effective date of the TMDL. Nonpoint source dischargers, such as
					 owners and/or operators of sanitary sewer collection systems, onsite wastewater
					 treatment systems (septic systems) and marine sanitation devices are to achieve
					 LAs from the effective date of the TMDL. Owners and/or operators of irrigated
					 agricultural land, golf courses and any other nonpoint sources are to achieve
					 LAs within 3 years.
Compliance with the MS4 WLAs is assessed through compliance
					 with MS4 permits. The MS4 WLAs will be implemented by permittees through their
					 Watershed Management Programs, which must be approved by the Los Angeles Water
					 Board. Compliance with the WLAs assigned to non-MS4 point source dischargers is
					 assessed through NPDES permits, with WQBELs in their NPDES permits at the time
					 of permit issuance, modification, or renewal.
Compliance with the LAs is assessed through compliance with
					 the Conditional Waiver for Irrigated Agricultural Lands (Order No.
					 R4-2021-0045-A02 or other successor order) or other appropriate mechanisms
					 consistent with the LAs and the State Water Board's Nonpoint Source
					 Implementation and Enforcement Policy. The LAs for OWTS will be regulated by
					 WDRs or waivers of WDRs consistent with the State Water Board's OWTS Policy.
					 LAs for golf courses will be implemented through WDRs or waivers of WDRs
					 consistent with the State Water Board's Nonpoint Source Implementation and
					 Enforcement Policy. The Nonpoint Source Implementation and Enforcement Policy
					 specifies that the regional water boards have the authority to regulate
					 nonpoint source discharges through WDRs, waivers, and prohibitions.
1. New
					 section summarizing amendment to basin plan filed 9-19-2023; amendment approved
					 by State Water Resources Control Board Resolution No. 2022-0053 on 12-6-2022;
					 amendment approved by OAL pursuant to Government Code section
					 11353 on
					 9-19-2023 (Register 2023, No. 38).