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 3939.35 - A Total Maximum Daily Load for Eutrophic, Algae, Ammonia, and Odors (Nutrient) for Machado Lake

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
The Los Angeles Regional Water Quality Control Board
					 (Regional Board) adopted Resolution No. R08-006 on May 1, 2008, which modified
					 the regulatory provisions of the Water Quality Control Plan for the Los Angeles
					 Region (Basin Plan) by (1) revising the Table of Contents, (2) adding
					 introductory text for Chapter 7 (Total Maximum Daily Loads), and (3)
					 establishing a Total Maximum Daily Load (TMDL) for Eutrophic, Algae, Ammonia,
					 and Odors (Nutrient) in Machado Lake.
The Basin Plan amendment establishes numeric targets for
					 total phosphorus, total nitrogen
					 (TKN+NO3-N+NO2-N), ammonia -- N
					 (chronic and acute), dissolved oxygen, and chlorophyll a. These numeric targets
					 are set to achieve the applicable Water Quality Objectives, which are
					 Biostimulatory Substances, Taste and Odor, Dissolved Oxygen, and Ammonia. The
					 TMDL waste load allocations (WLAs) for point source discharges and load
					 allocations (LAs) for nonpoint source discharges are established to attain the
					 TMDL numeric targets. Waste load allocations are assigned to urban stormwater
					 dischargers in both wet and dry weather. The final waste load allocations are
					 assigned as concentration based allocations of 0.1 mg/L and 1.0 mg/L as monthly
					 averages for total phosphorus and total nitrogen
					 (TKN+NO3-N+NO2-N), respectively.
					 Load allocations are assigned for nonpoint sources discharges to the lake,
					 primarily internal nutrient loading from the lake sediments. The final load
					 allocations for internal loading are concentration based allocations for 0.1
					 mg/L and 1.0 mg/L as monthly averages for total phosphorus and total nitrogen
					 (TKN+NO3-N+NO2-N),
					 respectively.
The regulatory mechanisms used to implement the TMDL
					 include the Los Angeles County municipal separate storm sewer system (MS4)
					 permit, the Caltrans stormwater permit, the general industrial stormwater NPDES
					 permit, and the general construction stormwater NPDES permit. Nonpoint sources
					 are regulated through a Memorandum of Agreement (MOA) between the responsible
					 parties and the Regional Board Executive Officer. The MOA shall comply with the
Water Quality Control Policy for Addressing Impaired Waters: Regulatory
					 Structure and Options
("Policy"), including part II section
					 2 c ii and related provisions. The
					 implementation of the MOA must result in attainment of the TMDL load
					 allocations. If the MOA does not result in the attainment of the TMDL load
					 allocations, the MOA will be rescinded and the load allocations shall be
					 implemented through a clean up and abatement order.
The TMDL requires stormwater permittees to achieve interim
					 waste load allocations upon the effective date of the TMDL and final waste load
					 allocations 9.5 years from the effective date of the TMDL. The TMDL requires
					 responsible parties assigned load allocations to achieve interim load
					 allocations upon the effective date of the TMDL and final load allocations 9.5
					 years from the effective date of the TMDL. The TMDL allows for special studies,
					 which are required to be completed within 6 years of the effective date. The
					 Regional Board shall reconsider the TMDL 7.5 years from the effective date
					 based on the results of special studies and water quality monitoring.
1. New
					 section summarizing amendments to the basin plan filed 2-19-2009; amendments
					 approved by State Water Resources Control Board Resolution No. R08-006 on
					 5-1-2008; amendments approved by OAL pursuant to Government Code section
					 11353 on
					 2-19-2009 (Register 2009, No. 8).