California Code of Regulations › Title 23 - Waters › Division 4 - Regional Water Quality Control Boards › Chapter 1 - Water Quality Control Plans, Policies, and Guidelines › Article 3 - Central Coast Region › Section 3929.12 - Total Maximum Daily Loads for Nitrogen Compounds and Orthophosphate in Lower Santa Maria River Wathershed and Tributaries to Oso Flaco Lake

Current through Register 2024 Notice Reg. No. 28, July 12, 2024
On May 30, 2013, the Regional Water Quality Control Board,
					 Central Coast Region (Water Board) adopted Resolution No. R3-2013-0013,
					 amending the Water Quality Control Plan for the Central Coastal Basin (Basin
					 Plan). Resolution No. R3-2013-0013 establishes the Lower Santa Maria River
					 Watershed and Tributaries to Oso Flaco Lake Total Maximum Daily Loads (TMDLs)
					 and Implementation Plan for nitrate, unionized ammonia and orthophosphate. The
					 TMDLs address nutrient-related impairments of the lower Santa Maria Valley,
					 which include the waterbodies Blosser Channel, Bradley Canyon Creek, Bradley
					 Channel, Greene Valley Creek, Main Street Canal, North Main Street Channel,
					 Orcutt Creek, Oso Flaco Creek, Little Oso Flaco Creek, Santa Maria River, and
					 Santa Maria River Estuary.
Current nutrient and nutrient-related impairments in lower
					 Santa Maria River Valley waters are impairing a range of current or potential
					 designated beneficial uses including aquatic habitat (COLD, WARM, SPWN),
					 drinking water supply (MUN), groundwater recharge (GWR), water contact
					 recreation (REC-1), and agricultural supply (AGR). The TMDLs set numeric
					 targets for nitrate, unionized ammonia, orthophosphate, dissolved oxygen,
					 chlorophyll
a,
and microcystins consistent with Basin Plan
					 narrative and numeric water quality objectives protective of the aforementioned
					 beneficial uses.
Responsibility for achieving waste load allocations and
					 load allocations falls upon several entities as described in the Resolution. An
					 implicit margin of safety is utilized in the TMDL to account for uncertainties.
					 The Water Board is relying on existing regulatory measures (i.e., the
					 Agricultural Order and storm water permits) to ensure implementation actions
					 are carried out by implementing parties. Interim and final implementation
					 milestones of 12, 20 and 30 years are established for showing progress and
					 achieving the TMDL. The Water Board will track progress towards achieving the
					 TMDL through review of implementation actions and monitoring conducted by the
					 implementing parties. Water Board staff will conduct triennial reviews of
					 implementation actions and monitoring results. If existing efforts are not
					 expected to achieve the TMDL as scheduled (as determined by triennial reviews),
					 the Executive Officer or the Water Board may require changes to existing
					 monitoring, reporting, or implementation efforts pursuant to California Water
					 Code Sections
					 13263,
					 13267 or
					 13383.
1. New
					 section summarizing amendments to basin plan filed 5-22-2014; amendment
					 approved by State Water Resources Control Board Resolution No. 2014-0009 on
					 2-4-2014; amendment approved by OAL pursuant to Government Code section
					 11353 on
					 5-22-2014 (Register 2014, No. 21).