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 3939.7 - A Total Maximum Daily Load for Nitrogen Compounds and Related Effects in the los Angeles River and Its Tributaries

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
Los Angeles Regional Water Quality Control Board (Regional
					 Board) Resolution No. 03-009, adopted on July 10, 2003 by the Regional Board,
					 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 nitrogen compounds and
					 related effects in the Los Angeles River and its tributaries. The TMDL
					 specifies concentration-based targets for ammonia, nitrate, nitrite, and
					 combined nitrate and nitrite, which must be fully attained five years after the
					 effective date of the TMDL. The TMDL includes a margin of safety with both
					 implicit and explicit components.
Numeric targets will primarily be achieved by limiting the
					 amount of nitrogen compounds discharged from three major wastewater treatment
					 plants (Donald C. Tillman Water Reclamation Plant, Los Angeles-Glendale Water
					 Reclamation Plant, and Burbank Water Reclamation Plant). To provide these major
					 permitted discharges time to meet wasteload allocations, higher interim limits
					 will be allowed for ammonia and combined nitrite and nitrate for a period of
					 3.5 years from the effective date of the TMDL. Compliance with the separate
					 nitrate and nitrite wasteload allocations is not required during this interim
					 period. Minor permitted point source dischargers are also assigned wasteload
					 allocations, which must be met immediately. Load allocations for nonpoint
					 sources may be developed if it is determined that they are necessary after
					 wasteload allocations have been implemented.
Workplans for monitoring nitrogen compounds and related
					 effects must be submitted by MS4 (municipal separate storm sewer systems)
					 permittees and major National Pollutant Discharge Elimination System permittees
					 within one year after the effective date of the TMDL. A special studies
					 workplan to evaluate site-specific objectives, seasonal allocations, and point
					 of compliance must be submitted by the City of Los Angeles within one year
					 after the effective date of the TMDL, and the results of the studies within two
					 and a half years after the effective date of the TMDL. Three and a half years
					 after the effective date of the TMDL, if monitoring and study results indicate
					 it is appropriate, the Regional Board will consider adopting site specific
					 objectives for ammonia, nitrate, and nitrite and revising the TMDL. Five years
					 after the effective date of the TMDL, the Regional Board will consider whether
					 the numeric targets and wasteload allocations specified in the TMDL are
					 sufficient to protect the Los Angeles River and its tributaries from the
					 nutrient effects of discharged nitrogen compounds or whether the TMDL must be
					 revised.
The Regional Board adopted Resolution No. 03-016 on
					 December 4, 2003, which modified regulatory provisions of the Basin Plan by
					 revising interim ammonia effluent limits for the Donald C. Tillman and Los
					 Angeles-Glendale Water Reclamation Plants (WRPs) contained within the TMDL for
					 nitrogen compounds and related effects for the Los Angeles River. The
					 thirty-day average and daily maximum interim limits for total ammonia as
					 nitrogen for the Donald C. Tillman WRP were changed from 21.0 and 21.7
					 milligrams per liter (mg/L), respectively, to 20.5 and 24.7 mg/L. For the Los
					 Angeles-Glendale WRP, the thirty-day average and daily maximum interim limits
					 for total ammonia as nitrogen were changed from 16.5 and 19.4 mg/L,
					 respectively, to 18.8 and 24.2 mg/L.
The Regional Board adopted Resolution No. 12-010 on
					 December 6, 2012, which modified regulatory provisions of the Basin Plan by
					 revising the TMDL for nitrogen compounds and related effects for the Los
					 Angeles River. The TMDL was revised to adjust the numeric targets for the
					 Burbank Western Channel and Reaches 3-5 of the Los Angeles River to reflect
					 formulaic site-specific 30-day ammonia objectives previously adopted as a Basin
					 Plan Amendment (23 CCR §
											3939.1).
					 Corresponding adjustments were made to the chronic ammonia waste load
					 allocations (WLAs) for:
(1) the Donald
				  C. Tillman, Burbank, and Los-Angeles Glendale WRPs,
(2) the minor point source WLAs for these
				  reaches, and
(3) the Whittier
				  Narrows WRP that can discharge into either the San Gabriel River or can be
				  routed through the Rio Hondo to the Los Angeles River. Confirmatory monitoring
				  requirements were added to ensure the site-specific objectives remain
				  protective of water quality.
1. New
					 section summarizing amendments to Basin Plan filed 2-27-2004; approved by OAL
					 2-27-2004 pursuant to Government Code section
					 11353
					 (Register 2004, No. 9).
2. Amendment to basin plan filed 6-9-2014;
					 amendments approved by State Water Resources Control Board 6-4-2013 pursuant to
					 Resolution No. 2013-0016; amendments approved by OAL pursuant to Government
					 Code section
					 11353
					 6-9-2014 (Register 2014, No. 24).