Draft California 2026 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 8 - Santa Ana Region

Water Body Name:	Tidal Prism of Greenville-Banning Channel
Water Body ID:	CAR8011100020210721060781
Water Body Type:	River & Stream


DECISION ID	133920	Region 8
Tidal Prism of Greenville-Banning Channel

Pollutant:	pH
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	New Decision
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 133920, pH	Region 8
Tidal Prism of Greenville-Banning Channel

LOE ID:

237390

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed Santa Ana River Regional Monitoring Program data for Tidal Prism of Greenville-Banning Channel to determine beneficial use support and results are as follows: 0 of 4 samples exceeded the water quality threshold for pH.

Data Reference:

Field, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH of bay or estuary waters shall not be raised above 8.6 or depressed below 7.0 as a result of controllable water quality factors; ambient pH levels shall not be changed more than 0.2 units (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Enclosed Bays and Estuaries).

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: P4-OC3 (Greenville-Banning Channel in Tidal Prism).

Temporal Representation:

The samples were collected between the dates of 2016-07-25 and 2019-09-23

Environmental Conditions:

QAPP Information:

CDM Smith. 2019. Santa Ana River Watershed Bacteria Monitoring Program.

QAPP Information Reference(s):

Santa Ana River Watershed Bacteria Monitoring Program