California Code of Regulations › Title 23 - Waters › Division 4 - Regional Water Quality Control Boards › Chapter 1 - Water Quality Control Plans, Policies, and Guidelines › Article 5 - Central Valley Region › Section 3949.2 - Program to Control Dissolved Oxygen in the Stockton Deep Water Ship Channel

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
Resolution No. R5-2005-0005, adopted by the Central Valley
					 Regional Water Quality Control Board (Central Valley Water Board) on January
					 27, 2005, modified the regulatory provisions of the Water Quality Control Plan
					 for the Sacramento and San Joaquin River Basins by incorporating a program for
					 the control of factors contributing to the dissolved oxygen impairment in the
					 Stockton Deep Water Ship Channel (DWSC). Impairment is defined in terms of
					 excess net oxygen demand (ENOD) and responsibility for reducing ENOD is
					 apportioned to the entities responsible for three factors that contribute to
					 the impairment (low flow, increased channel geometry, and loads of oxygen
					 demanding substances and their precursors (ODS)).
The program includes a Total Maximum Daily Load that
					 allocates percent of relative responsibility for the ENOD to the point source
					 and nonpoint source discharges that contribute ODS to the DWSC: 30 percent for
					 a waste load allocation for the City of Stockton Regional Wastewater Control
					 Facility; 60 percent for a load allocation for nonpoint sources (defined as
					 discharges from irrigated lands); and 10 percent as a reserve for impacts from
					 unknown sources and/or minor sources. An explicit margin of safety of 20
					 percent is incorporated. The Central Valley Water Board has committed to
					 reviewing and updating the load allocations, waste load allocations, and
					 prohibitions (mentioned below) by December 2009.
Entities responsible for sources of ODS are required to
					 perform studies by December 2008 that identify and quantify:
1) sources of ODS in the source
				  area;
2) growth or degradation
				  mechanisms of ODS in transit to the DWSC; and
3) the impact of ODS on dissolved oxygen
				  concentrations in the DWSC under a range of environmental conditions. Within 60
				  days from the effective date of this amendment, responsible entities must
				  submit a study plan for the Central Valley Water Board describing how ongoing
				  studies and future studies will address information needs.
Upon the effective date of this amendment, any increases in
					 the discharge of ODS into waters tributary to the DWSC is prohibited unless the
					 discharge is regulated by a waiver of waste discharge requirements, or
					 individual or general waste discharge requirements or National Pollution
					 Discharge Elimination System (NPDES) permits, which either implement the
					 amendment or include a finding that the discharge will have no reasonable
					 potential to cause or contribute to the dissolved oxygen impairment in the
					 DWSC.
After December 31, 2011, the discharge of ODS into waters
					 tributary to the DWSC is prohibited when net daily flow in the DWSC is less
					 than 3,000 cubic feet per second, unless dissolved oxygen objectives in the
					 DWSC are being met or the discharge is regulated by a waiver of waste discharge
					 requirements, or individual or general waste discharge requirements or National
					 Pollution Discharge Elimination System (NPDES) permits, which either implement
					 the amendment; or include a finding that the discharge will have no reasonable
					 potential to cause or contribute to the dissolved oxygen impairment in the
					 DWSC.
The United States Army Corps of Engineers must submit by
					 December 31, 2006 a technical report identifying and quantifying:
1) the chemical, biological, and physical
				  mechanisms by which loads of substances into, or generated within the DWSC, are
				  converted to oxygen demand; and
2)
				  the impact that the Stockton Deep Water Ship Channel has on re-aeration and
				  other mechanisms that affect dissolved oxygen concentrations in the water
				  column.
Any project that requires a Clean Water Act Section
					 401 Water Quality Certification
					 and that has the potential to impact dissolved oxygen conditions in the DWSC
					 must evaluate and fully mitigate those impacts. The Central Valley Water Board
					 may consider alternate measures, as opposed to direct control, of certain
					 contributing factors if these measures adequately address the impact on the
					 dissolved oxygen impairment and do not degrade water quality in any other way.
					 Compliance with waste load allocations and load allocations for ODS, and
					 development of alternate measures to address non-load related factors must be
					 achieved by December 31, 2011.
1. New
					 section summarizing amendment of Basin Plan filed 8-4-2006; amendment approved
					 by State Water Resources Control Board Resolution No. 2006-0086 11-16-2005;
					 amendment approved by OAL pursuant to Government Code section
					 11353
					 8-4-2006 (Register 2006, No. 31).