Draft California 2024 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 8 - Santa Ana Region

Water Body Name:	San Diego Creek Reach 2
Water Body ID:	CAR8011100019990211130358
Water Body Type:	River & Stream


DECISION ID	153829	Region 8
San Diego Creek Reach 2

Pollutant:	Benthic Community Effects
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	A Source Unknown
Expected TMDL Completion Date:	2027
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Benthic Community Effects is being considered for placement on the CWA section 303(d) List under sections 3.9 and 3.1 of the Listing Policy. Under section 3.9, an additional line of evidence associating Benthic Community Effects with a water or sediment concentration of pollutant(s) is necessary to assess listing status. Six lines of evidence are available. Five of the 5 benthic invertebrate samples exceed (fall below) the Southern California IBI threshold for poor community composition. One of one CSCI samples exceed (fall below) the California Stream Condition Index. This water segment is also on the CWA section 303(d) List for nutrients, sedimentation/siltation, toxaphene, and toxicity. Based on the readily available data and information, the weight of evidence provides sufficient justification for placing Benthic Community Effects in this water segment on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Pursuant to section 3.9 of the Listing Policy, the water segment exhibits significant degradation in biological populations and/or communities as compared to reference site(s) using the SoCal IBI and the CSCI. 4. Pursuant to section 3.9 of the Listing Policy, the water segment has associated pollutant(s) samples that exceed water quality objectives. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are being met. The California Stream Condition Index is a new scoring tool for bioassessment data that is applicable statewide, accounts for a much wider range of natural variability, and provides equivalent scoring thresholds in all regions of the state. The CSCI has been used in some assessments this reporting cycle and will be used in the future for water quality assessment purposes statewide over the regional indices of biologic integrity (IBIs). If CSCI scores have not be calculated for data and only IBI scores are available, IBI scores will still be used to interpret the data. CSCI scores representing min and max scores for this site were submitted by OCPW during our comment period. The CSCI scores do not change the listing decision and the IBI LOEs will be retired when the CSCI LOEs are written.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem. Based on the readily available data and information, the weight of evidence provides sufficient justification for placing Benthic Community Effects in this water segment on the CWA section 303(d) List.

State Board Review of Regional Board Conclusion and Recommendation:	The California Stream Condition Index is a new scoring tool for bioassessment data that is applicable statewide, accounts for a much wider range of natural variability, and provides equivalent scoring thresholds in all regions of the state. The CSCI has been used in some assessments this reporting cycle and will be used in the future for water quality assessment purposes statewide over the regional indices of biologic integrity (IBIs). If CSCI scores have not be calculated for data and only IBI scores are available, IBI scores will still be used to interpret the data. CSCI scores representing min and max scores for this site were submitted by OCPW during our comment period. The CSCI scores do not change the listing decision and the IBI LOEs will be retired when the CSCI LOEs are written.

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 153829, Benthic Community Effects	Region 8
San Diego Creek Reach 2

LOE ID:

2971

Pollutant:

Sedimentation/Siltation

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 153829, Benthic Community Effects	Region 8
San Diego Creek Reach 2

LOE ID:

2970

Pollutant:

Nutrients

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 153829, Benthic Community Effects	Region 8
San Diego Creek Reach 2

LOE ID:

82230

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Five out of the five samples collected had IBI scores below 40. The scores were, fall 2006: 1.43, spring 2007: 4.29, fall 2007: 2.86, spring 2008: 12.87, fall 2008: 27.17.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Region 8 Basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

The IBI is a multi-metric assessment that employs biological metrics that respond to a habitat or water quality impairment. Each of the biological metrics measured at a site are converted to an IBI score then summed. These cumulative scores are then ranked. For the Southern California IBI, sites with scores below 40 are considered to have impaired conditions.

Guideline Reference:

A Quantitative Tool for Assessing the Integrity of Southern Coastal California Streams. Environmental Management. Volume 35, number 1 (2005): pp. 1-13

Spatial Representation:

Samples were collected at station LCRF05, San Diego Creek near Laguna Canyon Road.

Temporal Representation:

The samples were collected in the fall 2006, and the spring and fall of 2007 and 2008.

Environmental Conditions:

QAPP Information:

The taxonomic analysis followed the guidelines of the Southern California Freshwater and Marine Invertebrate Taxonomic Associations (SAFIT, SCAMIT). All stream bioassessment sample collection and taxonomic analysis follow the Southern California Regional Watershed Monitoring Program Bioassessment Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 153829, Benthic Community Effects	Region 8
San Diego Creek Reach 2

LOE ID:

314313

Pollutant:

Benthic-Macroinvertebrate Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Water Board staff assessed data for 801S19399 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.430850829 to 0.430850829.

Data Reference:

California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 8.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Inland surface water communities and populations, including vertebrate, invertebrate, and plant species, shall not be degraded as a result of the discharge of waste. Degradation is damage to an aquatic community or population with the result that balanced community no longer exists. The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.

Guideline Reference:

Bioassessment in complex environments: designing an index for consistent meaning in different settings

Spatial Representation:

Samples were collected from station 801S19399.

Temporal Representation:

Samples were collected from 6/13/2013 to 6/13/2013.

Environmental Conditions:

QAPP Information:

Data collected following SWAMP QA protocols.

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 153829, Benthic Community Effects	Region 8
San Diego Creek Reach 2

LOE ID:

2969

Pollutant:

Unknown Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 153829, Benthic Community Effects	Region 8
San Diego Creek Reach 2

LOE ID:

82244

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Six samples were collected to test for toxicity. Three of the six samples exhibited statistically significant toxicity. The toxicity tests that exhibited significant toxicity included Ceriodaphnia reproduction and Hyallela survival.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Region 8 Basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control. Exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.

Guideline Reference:

Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013

Spatial Representation:

The sample was collected at station LCRF05 San Diego Creek.

Temporal Representation:

The sample was collected from 2006 to 2010.

Environmental Conditions:

QAPP Information:

The data collected under the Quality Assurance Management Plan for The Orange County Stormwater Program. The SWAMP measurement quality objectives were followed for toxicity data. The performance of toxicity bioassays and evaluation of reference toxicants were performed using USEPA and Standard Methods.

QAPP Information Reference(s):


DECISION ID	132599	Region 8
San Diego Creek Reach 2

Pollutant:	Toxicity
Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status	Revised
Sources:	Unknown Nonpoint Source
TMDL Name:	Newport Bay Watershed Diazinon/Chlorpyrifos TMDLs
TMDL Project Code:	151
Date TMDL Approved by USEPA:	02/13/2004
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.6 of the Listing Policy. Under section 4.6 of the Policy, a minimum of one line of evidence is needed to assess listing status for toxicity. Five lines of evidence are available in the administrative record to assess this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Four of the eight water samples exceed the WARM Toxicity guideline and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy. LOE ID 2969 also indicates a listing made prior to 2006. 4. The Newport Bay Watershed Diazinon/Chlorpyrifos TMDL was approved by RWQCB on April 4, 2003 and subsequently approved by USEPA on February 13, 2004. 5. A new LOE suggests other pollutants other than diazinon/chlorpyrifos may contribute to the toxicity. 6. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 132599, Toxicity	Region 8
San Diego Creek Reach 2

LOE ID:

2969

Pollutant:

Unknown Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132599, Toxicity	Region 8
San Diego Creek Reach 2

LOE ID:

238241

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

1 of the 1 samples collected by SWAMP RWB8 Monitoring for San Diego Creek Reach 2 exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Chironomus dilutus for Survival, Chironomus dilutus for Growth (wt/surv indiv), Hyalella azteca for Survival. The following tests exhibited toxicity: Hyalella azteca for Survival on 2019-04-30.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing. An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold. The default evaluation threshold is 20% unless otherwise stated.

Guideline Reference:

Spatial Representation:

The samples were collected at monitoring site: 801SDCT01 ( San Diego Creek above Hwy 133 ).

Temporal Representation:

The samples were collected between the dates of 2019-04-30 and 2019-04-30.

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132599, Toxicity	Region 8
San Diego Creek Reach 2

LOE ID:

238235

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

1 of the 1 samples collected by RWB8 So. CA Stormwater Monitoring Coalition for San Diego Creek Reach 2 exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia for Survival, Ceriodaphnia dubia for Young/female. The following tests exhibited toxicity: Ceriodaphnia dubia for Young/female on 2013-06-13.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at monitoring site: 801S19399 ( San Diego Creek Randon SMC Site 19399 ).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13.

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132599, Toxicity	Region 8
San Diego Creek Reach 2

LOE ID:

238233

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

0 of the 1 samples collected by SWAMP RWB8 Monitoring for San Diego Creek Reach 2 exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia for Survival, Ceriodaphnia dubia for Young/female.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at monitoring site: 801SDC504 ( San Diego Creek Random Olsen Site 504 ).

Temporal Representation:

The samples were collected between the dates of 2012-06-19 and 2012-06-19.

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132599, Toxicity	Region 8
San Diego Creek Reach 2

LOE ID:

82244

Pollutant:

Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Region 8 Basin Plan.

Objective/Criterion Reference:

Water Quality Control Plan for the San Diego Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The sample was collected at station LCRF05 San Diego Creek.

Temporal Representation:

The sample was collected from 2006 to 2010.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	132601	Region 8
San Diego Creek Reach 2

Pollutant:	Alkalinity as CaCO3
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:

Line of Evidence (LOE) for Decision ID 132601, Alkalinity as CaCO3	Region 8
San Diego Creek Reach 2

LOE ID:

235080

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB8 Monitoring data for San Diego Creek Reach 2 to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801SDC504 (San Diego Creek Random Olsen Site 504).

Temporal Representation:

The samples were collected between the dates of 2012-06-19 and 2012-06-19

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132601, Alkalinity as CaCO3	Region 8
San Diego Creek Reach 2

LOE ID:

235075

Pollutant:

Alkalinity as CaCO3

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for San Diego Creek Reach 2 to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	150606	Region 8
San Diego Creek Reach 2

Pollutant:	Ammonia
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 150606, Ammonia	Region 8
San Diego Creek Reach 2

LOE ID:

82239

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

One of five samples exceed the water quality objective.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Santa Ana Basin Plan 4-day chronic objective for unionized ammonia and corresponding total ammonia in waters supporting warm freshwater aquatic life is determined by an equation dependent on pH and temperature.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected at Laguna Canyon Road.

Temporal Representation:

Samples were collected biannually from October 2006 to September 2008.

Environmental Conditions:

QAPP Information:

A signed QAPP was included with the stated goal of ensuring the consistent collection of accurate water quality information that will used to satisfy the objectives of the Orange County Stormwater Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 150606, Ammonia	Region 8
San Diego Creek Reach 2

LOE ID:

235350

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801SDC504 (San Diego Creek Random Olsen Site 504).

Temporal Representation:

The samples were collected between the dates of 2012-06-19 and 2012-06-19

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	132590	Region 8
San Diego Creek Reach 2

Pollutant:	Arsenic
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of 36 samples exceed the beneficial use criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 36 samples exceed the beneficial use criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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 because applicable water quality standards are not being exceeded.

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 132590, Arsenic	Region 8
San Diego Creek Reach 2

LOE ID:

82229

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the five samples exceeded the water quality objective for arsenic.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The CTR for arsenic is 150 ug/L.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Diego Creek Reach 2 at Laguna Canyon Road, station LCRF05.

Temporal Representation:

Samples were collected on 10/5/06, 6/6/07, 10/10/07, 5/13/08 and 9/30/08.

Environmental Conditions:

Samples are representative of dry weather conditions.

QAPP Information:

Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132590, Arsenic	Region 8
San Diego Creek Reach 2

LOE ID:

7585

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 31 samples none exceeded the California Toxics Rule Standard for acute or chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule Acute Criteria Arsenic: 340 ppb.
California Toxics Rule Chronic Criteria Arsenic: 150 ppb.

Objective/Criterion Reference:

Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 4 locations as follows: San Diego Creek at Jefferson (SDJF05), san Diego Creek at Laguna Canyon Road (LCRF05), San Diego Creek at Sand Canyon (SSCF05), and West Yale Loop (WYLSED).

Temporal Representation:

The data evaluation period is October 2000 thorugh December 2006. The samples were collected at WYLSED during the dry weather on the following dates: 2/11/03, 8/21/05, 11/1/05, 2/1/06, 6/26/06.
The samples were collected at LCRF05 during the dry weather on the following dates: 10/13/05, 7/13/06, 10/5/06.
The samples were collected at SDJF05 during the dry weather on the following dates: 5/2/06, 7/14/06, 7/27/06, 8/2/06, 8/10/06, 8/22/06, 8/29/06.
The samples were collected at SSCF05 during the dry weather on the following dates: 8/22/06, 10/11/06, 11/15/06, 12/7/06. The samples were collected at WYLSED during the wet weather on the following dates: 11/8/02, 11/10/02, 2/11/03, 10/17/05, 10/18/05, 2/27/06, 3/1/06, 3/3/06.

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132590, Arsenic	Region 8
San Diego Creek Reach 2

LOE ID:

235803

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 150 ug/L. The conversion factor used to convert the total fraction criterion for arsenic to dissolved fraction criterion is 1. Therefore all data was considered to be representative of the dissolved fraction. (California Toxics Rule, 2000)

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	132591	Region 8
San Diego Creek Reach 2

Pollutant:	Cadmium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Three lines of evidence are available to assess this pollutant. Zero of the 121 samples exceed the WARM Cadmium criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 121 samples exceed the WARM Cadmium criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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 because applicable water quality standards are not being exceeded.

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 132591, Cadmium	Region 8
San Diego Creek Reach 2

LOE ID:

236077

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved cadmium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.2 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132591, Cadmium	Region 8
San Diego Creek Reach 2

LOE ID:

7723

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples none exceeded the California Toxics Rule Standards for acute or chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 2.45 ug/l to 40.96 ug/l. The chronic criteria ranged from 1.53 ug/l to 10.45 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

The data evaluation period is October 2000 thorugh December 2006. The samples were collected at WYLSED during the dry weather on the following dates: 2/11/03, 7/14/04, 7/20/04, 8/24/04, 9/7/04, 9/29/04, 10/11/04, 11/16/04, 11/30/04, 3/2/05, 3/16/05, 4/5/05, 5/3/05, 5/10/05, 6/14/05, 6/28/05, 7/5/05, 7/12/05, 8/4/05, 8/8/05, 8/21/05, 9/6/05, 9/20/05, 10/5/05, 11/1/05, 11/29/05, 12/22/05, 12/28/05, 1/11/06, 2/1/06, 3/21/06, 4/17/06, 4/24/06, 5/1/06, 5/17/06, 6/13/06, 6/26/06.

The samples were collected at LCRF05 during the dry weather on the following dates: 10/13/05, 7/13/06, 10/5/06.

The samples were collected at SDJF05 during the dry weather on the following dates: 5/2/06, 7/14/06, 7/27/06, 8/2/06, 8/10/06, 8/22/06, 8/29/06.

The samples were collected at SSCF05 during the dry weather on the following dates: 8/22/06, 10/11/06, 11/15/06, 12/7/06.

The samples were collected at WYLSED during the wet weather on the following dates: 10/27/00, 10/29/00, 10/30/00, 1/8/01, 1/9/01, 1/10/01, 1/24/01, 1/25/01, 1/26/01, 3/6/01, 11/12/01, 11/14/01, 11/24/01, 11/25/01, 11/27/01, 11/30/01, 12/14/01, 12/16/01, 2/17/02, 2/18/02, 3/7/02, 3/8/02, 11/8/02, 11/10/02, 2/11/03, 1/2/04, 2/25/04, 2/26/04, 4/17/04, 4/19/04, 4/20/04, 10/26/04, 10/27/04, 10/28/04, 10/29/04, 10/30/04, 12/28/04,12/31/04, 1/1/05, 5/6/05, 5/7/05, 5/9/05, 10/17/05, 10/18/05, 2/27/06, 3/1/06, 3/3/06.

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132591, Cadmium	Region 8
San Diego Creek Reach 2

LOE ID:

82231

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the five samples exceeded the water quality objective for cadmium.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The disolved criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Diego Creek Reach 2 at Laguna Canyon Road, station LCRF05.

Temporal Representation:

Samples were collected on 10/5/06, 6/6/07, 10/10/07, 5/13/08 and 9/30/08.

Environmental Conditions:

Samples are representative of dry weather conditions.

QAPP Information:

Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.

QAPP Information Reference(s):


DECISION ID	132602	Region 8
San Diego Creek Reach 2

Pollutant:	Chromium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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 132602, Chromium	Region 8
San Diego Creek Reach 2

LOE ID:

82233

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the five samples exceeded the water quality objective for chromium.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Diego Creek Reach 2 at Laguna Canyon Road, station LCRF05.

Temporal Representation:

Samples were collected on 10/5/06, 6/6/07, 10/10/07, 5/13/08 and 9/30/08.

Environmental Conditions:

Samples are representative of dry weather conditions.

QAPP Information:

Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132602, Chromium	Region 8
San Diego Creek Reach 2

LOE ID:

235859

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved chromium (III) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is is hardness dependent as described in Table 1 of paragraph (b)(1). The value calculated when using a default hardness of 100 mg/L is 180 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	132592	Region 8
San Diego Creek Reach 2

Pollutant:	Copper
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Five of the 230 samples exceed the WARM Copper criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of the 230 samples exceed the WARM Copper criterion. This does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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 because applicable water quality standards are not being exceeded.

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 132592, Copper	Region 8
San Diego Creek Reach 2

LOE ID:

82234

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the five samples exceeded the water quality objective for copper.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Diego Creek Reach 2 at Laguna Canyon Road, station LCRF05.

Temporal Representation:

Samples were collected on 10/5/06, 6/6/07, 10/10/07, 5/13/08 and 9/30/08.

Environmental Conditions:

Samples are representative of dry weather conditions.

QAPP Information:

Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132592, Copper	Region 8
San Diego Creek Reach 2

LOE ID:

7727

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples 1 exceeded the California Toxics Rule Standard for acute toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 8.31 ug/l to 96.46 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132592, Copper	Region 8
San Diego Creek Reach 2

LOE ID:

235851

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132592, Copper	Region 8
San Diego Creek Reach 2

LOE ID:

7728

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples 4 exceeded the California Toxics Rule Standard for chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR chronic criteria is hardness dependent and ranged from 5.79 ug/l to 53.51 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):


DECISION ID	132593	Region 8
San Diego Creek Reach 2

Pollutant:	Lead
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. One of the 236 water samples exceed the WARM Lead criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of the 236 water samples exceed the WARM Lead criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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 because applicable water quality standards are not being exceeded.

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 132593, Lead	Region 8
San Diego Creek Reach 2

LOE ID:

236731

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved lead criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132593, Lead	Region 8
San Diego Creek Reach 2

LOE ID:

82236

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the five samples exceeded the water quality objective for lead.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Diego Creek Reach 2 at Laguna Canyon Road, station LCRF05.

Temporal Representation:

Samples were collected on 10/5/06, 6/6/07, 10/10/07, 5/13/08 and 9/30/08.

Environmental Conditions:

Samples are representative of dry weather conditions.

QAPP Information:

Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132593, Lead	Region 8
San Diego Creek Reach 2

LOE ID:

7731

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples 1 exceeded the California Toxics Rule Standard for chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR chronic criteria is hardness dependent and ranged from 1.44 ug/l to 22.18 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132593, Lead	Region 8
San Diego Creek Reach 2

LOE ID:

7730

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Of the 115 samples 0 exceeded the California Toxics Rule Standard for acute toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 36.88 ug/l to 569.17 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):


DECISION ID	132594	Region 8
San Diego Creek Reach 2

Pollutant:	Nickel
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 121 samples exceed the WARM Nickel criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of the 121 samples exceed the WARM Nickel criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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 because applicable water quality standards are not being exceeded.

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 132594, Nickel	Region 8
San Diego Creek Reach 2

LOE ID:

82238

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the five samples exceeded the water quality objective for nickel.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Diego Creek Reach 2 at Laguna Canyon Road, station LCRF05.

Temporal Representation:

Samples were collected on 10/5/06, 6/6/07, 10/10/07, 5/13/08 and 9/30/08.

Environmental Conditions:

Samples are representative of dry weather conditions.

QAPP Information:

Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132594, Nickel	Region 8
San Diego Creek Reach 2

LOE ID:

7725

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples none exceeded the California Toxics Rule Standard for acute or chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 303.93 ug/l to 2748.17 ug/l. The chronic criteria ranged from 33.76 ug/l to 305.24 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132594, Nickel	Region 8
San Diego Creek Reach 2

LOE ID:

236487

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved nickel criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 52 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	132595	Region 8
San Diego Creek Reach 2

Pollutant:	Oxygen, Dissolved
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 132595, Oxygen, Dissolved	Region 8
San Diego Creek Reach 2

LOE ID:

236995

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).

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: 801SDCT01 (San Diego Creek above Hwy 133).

Temporal Representation:

The samples were collected between the dates of 2019-04-30 and 2019-04-30

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132595, Oxygen, Dissolved	Region 8
San Diego Creek Reach 2

LOE ID:

237045

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132595, Oxygen, Dissolved	Region 8
San Diego Creek Reach 2

LOE ID:

237488

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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: 801SDC504 (San Diego Creek Random Olsen Site 504).

Temporal Representation:

The samples were collected between the dates of 2012-06-19 and 2012-06-19

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	132597	Region 8
San Diego Creek Reach 2

Pollutant:	Selenium
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 132597, Selenium	Region 8
San Diego Creek Reach 2

LOE ID:

82241

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the five samples exceeded the water quality objective for selenium.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The CTR for selenium is 5.0 ug/L.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Diego Creek Reach 2 at Laguna Canyon Road, station LCRF05.

Temporal Representation:

Samples were collected on 10/5/06, 6/6/07, 10/10/07, 5/13/08 and 9/30/08.

Environmental Conditions:

Samples are representative of dry weather conditions.

QAPP Information:

Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132597, Selenium	Region 8
San Diego Creek Reach 2

LOE ID:

237523

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	132598	Region 8
San Diego Creek Reach 2

Pollutant:	Temperature, water
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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 the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 132598, Temperature, water	Region 8
San Diego Creek Reach 2

LOE ID:

237828

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The temperature of waters designated WARM shall not be raised above 90 degrees F June through October or above 78 degrees F during the rest of the year as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).

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: 801SDCT01 (San Diego Creek above Hwy 133).

Temporal Representation:

The samples were collected between the dates of 2019-04-30 and 2019-04-30

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132598, Temperature, water	Region 8
San Diego Creek Reach 2

LOE ID:

238090

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132598, Temperature, water	Region 8
San Diego Creek Reach 2

LOE ID:

82243

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Numeric data generated from 5 averages of temperature had no exceedences.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

At no time shall warm freshwater habitat-designated waters be raised above 80 degrees Fahrenheit as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the LCRF05 station.

Temporal Representation:

Samples were collected approximately semi-annually from October 2006 to September 2008.

Environmental Conditions:

QAPP Information:

NPDES quality assurance.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132598, Temperature, water	Region 8
San Diego Creek Reach 2

LOE ID:

237827

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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: 801SDC504 (San Diego Creek Random Olsen Site 504).

Temporal Representation:

The samples were collected between the dates of 2012-06-19 and 2012-06-19

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	132600	Region 8
San Diego Creek Reach 2

Pollutant:	Zinc
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Zero (0) of the one-hundred twenty (120) samples exceed the beneficial use criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero (0) of the one-hundred twenty (120) samples exceed the beneficial use criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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 because applicable water quality standards are not being exceeded.

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 132600, Zinc	Region 8
San Diego Creek Reach 2

LOE ID:

82245

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the five samples exceeded the water quality objective for zinc.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Diego Creek Reach 2 at Laguna Canyon Road, station LCRF05.

Temporal Representation:

Samples were collected on 10/5/06, 6/6/07, 10/10/07, 5/13/08 and 9/30/08.

Environmental Conditions:

Samples are representative of dry weather conditions.

QAPP Information:

Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132600, Zinc	Region 8
San Diego Creek Reach 2

LOE ID:

7726

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples none exceeded the California Toxics Rule Standard for acute or chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 76.01 ug/l to 689.63 ug/l. The chronic criteria ranged from 76.63 ug/l to 695.27 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 132600, Zinc	Region 8
San Diego Creek Reach 2

LOE ID:

238088

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved zinc criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 120 ug/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.


DECISION ID	132596	Region 8
San Diego Creek Reach 2

Pollutant:	pH
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2018)
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 132596, pH	Region 8
San Diego Creek Reach 2

LOE ID:

237144

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).

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: 801SDC504 (San Diego Creek Random Olsen Site 504).

Temporal Representation:

The samples were collected between the dates of 2012-06-19 and 2012-06-19

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132596, pH	Region 8
San Diego Creek Reach 2

LOE ID:

237482

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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: 801S19399 (San Diego Creek Randon SMC Site 19399).

Temporal Representation:

The samples were collected between the dates of 2013-06-13 and 2013-06-13

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132596, pH	Region 8
San Diego Creek Reach 2

LOE ID:

237145

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB8 Monitoring data for San Diego Creek Reach 2 to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.

Data Reference:

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

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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: 801SDCT01 (San Diego Creek above Hwy 133).

Temporal Representation:

The samples were collected between the dates of 2019-04-30 and 2019-04-30

Environmental Conditions:

QAPP Information:

SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..

QAPP Information Reference(s):

This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.

Line of Evidence (LOE) for Decision ID 132596, pH	Region 8
San Diego Creek Reach 2

LOE ID:

82240

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Numeric data generated from 5 minimums and maximums of pH data had 1 exceedence.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH of all inland surface waters shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Samples were collected from the LCRF05 station.

Temporal Representation:

Samples were collected approximately semi-annually from October 2006 to September 2008.

Environmental Conditions:

QAPP Information:

NPDES quality assurance.

QAPP Information Reference(s):


DECISION ID	76339	Region 8
San Diego Creek Reach 2

Pollutant:	Metals
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (TMDL required list)(2016)
Revision Status	Original
Reason for Delisting:	Applicable WQS attained; reason for recovery unspecified
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	There was no new data considered in the 2014 Listing Cycle, this previously made decision will carryover. The following description applies to an earlier Listing Cycle. This pollutant is being considered for removal from the section 303(d) list under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. This water body was originally listed because on October 31, 1997, EPA entered into a consent decree, Defend the Bay, Inc. v. Marcus, (N.D. Cal. No. C 97-3997 MMC), which established a schedule for development of TMDLs in San Diego Creek and Newport Bay. The decree required development of TMDLs for several toxic pollutants by January 15, 2002. Metals were included in the list of toxic pollutants. The current data indicates that the standards are being met and the listing is no longer applicable. Eleven lines of evidence are available in the administrative record to assess this pollutant. None of the samples that were analyzed for arsenic, cadmium, nickel chromium, and zinc exceeded the standards. Five (5) samples analyzed for copper and one sample analyzed for lead exceeded the standards. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for removing this water segment-pollutant combination from the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of 31 samples for arsenic, none of one hundred fifteen samples for cadmium, none of one hundred fifteen samples for chromium, none of one hundred fifteen samples for nickel, and none of one hundred fifteen samples for zinc, five of two hundred thirty samples for copper, and one of two hundred thirty samples for lead exceeded the California Toxics Rule and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current. The decision has not changed.

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 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7723

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples none exceeded the California Toxics Rule Standards for acute or chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 2.45 ug/l to 40.96 ug/l. The chronic criteria ranged from 1.53 ug/l to 10.45 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7585

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 31 samples none exceeded the California Toxics Rule Standard for acute or chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

California Toxics Rule Acute Criteria Arsenic: 340 ppb.
California Toxics Rule Chronic Criteria Arsenic: 150 ppb.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7726

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples none exceeded the California Toxics Rule Standard for acute or chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 76.01 ug/l to 689.63 ug/l. The chronic criteria ranged from 76.63 ug/l to 695.27 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7729

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples 1 exceeded the California Toxics Rule Standard for acute toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 1.43 ug/l to 126.01 ug/l. The CTR does not have a chronic toxicity standard that applies to silver.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7725

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples none exceeded the California Toxics Rule Standard for acute or chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 303.93 ug/l to 2748.17 ug/l. The chronic criteria ranged from 33.76 ug/l to 305.24 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7730

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Of the 115 samples 0 exceeded the California Toxics Rule Standard for acute toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 36.88 ug/l to 569.17 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7731

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples 1 exceeded the California Toxics Rule Standard for chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR chronic criteria is hardness dependent and ranged from 1.44 ug/l to 22.18 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7727

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples 1 exceeded the California Toxics Rule Standard for acute toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 8.31 ug/l to 96.46 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7728

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples 4 exceeded the California Toxics Rule Standard for chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR chronic criteria is hardness dependent and ranged from 5.79 ug/l to 53.51 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 76339, Metals	Region 8
San Diego Creek Reach 2

LOE ID:

7724

Pollutant:

Chromium (total)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples none exceeded the California Toxics Rule Standard for acute or chronic toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 361.14 ug/l to 2795.29 ug/l. The chronic criteria ranged from 117.15 ug/l to 987.37 ug/l.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):


DECISION ID	97833	Region 8
San Diego Creek Reach 2

Pollutant:	Chlorpyrifos
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	303(d) listing / TMDL decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed. This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero (0) of the five (5) samples exceed the beneficial use criteria. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero (0) of the five (5) samples exceed the beneficial use criteria and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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 because applicable water quality standards are not being exceeded.

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 97833, Chlorpyrifos	Region 8
San Diego Creek Reach 2

LOE ID:

82232

Pollutant:

Chlorpyrifos

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of 5 samples exceed the continuous concentration (four day average) for chlorpyrifos in freshwater is 14.0 ng/L.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

The Criteria Continuous Concentration (four day average) for chlorpyrifos in freshwater is 14.0 ng/L.

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Samples were collected at site: LCRF05

Temporal Representation:

Samples were collected from 2006 to 2008.

Environmental Conditions:

QAPP Information:

Data were submitted with the County of Orange Stormwater Program Quality Assurance Management Plan (QAMP) dated January 2010. The Regional Water Board has determined that equivalent QA/QC documentation exists within the Water Quality Monitoring and Reporting Program for the Orange County MS4 permit and appendix C-11- X of the 2008-09 monitoring report.

QAPP Information Reference(s):

Quality Assurance Project Plan for the Orange County Stormwater Program.


DECISION ID	99518	Region 8
San Diego Creek Reach 2

Pollutant:	Diazinon
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	303(d) listing / TMDL decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed. This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero (0) of the five (5) samples exceed the beneficial use criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero (0) of the five (5) samples exceed the beneficial use criterion and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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 99518, Diazinon	Region 8
San Diego Creek Reach 2

LOE ID:

82235

Pollutant:

Diazinon

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of 5 samples exceeded the continuous concentration for Diazinon criteria of 50.0 ng/L.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

CDFG Hazard Assessment criteria for the protection of Aquatic life is as follows: 50.0 ng/L Continuous Concentration for diazinon in freshwater. (Siepman & Finlayson, 2000).

Guideline Reference:

Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game

Spatial Representation:

Samples were collected at site: LCRF05

Temporal Representation:

Samples were collected from 2006 through 2008.

Environmental Conditions:

QAPP Information:

Data were submitted with the County of Orange Stormwater Program Quality Assurance Management Plan (QAMP) dated January 2010. However, data were collected prior to the development of this QAMP, therefore the quality of these data are unknown.

QAPP Information Reference(s):


DECISION ID	97835	Region 8
San Diego Creek Reach 2

Pollutant:	Malathion
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero (0) of the five (5) samples exceed the beneficial use criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero (0) of the five (5) samples exceed the beneficial use criterion and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1.

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 97835, Malathion	Region 8
San Diego Creek Reach 2

LOE ID:

82237

Pollutant:

Malathion

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of 5 samples exceed the maximum (Instantaneous) concentration for Malathion in freshwater of 100 ng/L.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

The maximum (Instantaneous) concentration for Malathion in freshwater is 100 ng/L.

Guideline Reference:

Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C

Spatial Representation:

Samples were collected at site: LCRF05

Temporal Representation:

Samples were collected from 2006 to 2008.

Environmental Conditions:

QAPP Information:

QAPP Information Reference(s):


DECISION ID	99424	Region 8
San Diego Creek Reach 2

Pollutant:	Silver
Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. One (1) of one-hundred twenty (120) samples exceed the CTR criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One (1) of one-hundred twenty (120) samples exceed the CTR criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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 because applicable water quality standards are not being exceeded.

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 99424, Silver	Region 8
San Diego Creek Reach 2

LOE ID:

7729

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

115

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Of the 115 samples 1 exceeded the California Toxics Rule Standard for acute toxicity.

Data Reference:

Program Effectiveness Assessment Section of the Unified Annual Progress Report for the period of time 2001-2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

CTR acute criteria is hardness dependent and ranged from 1.43 ug/l to 126.01 ug/l. The CTR does not have a chronic toxicity standard that applies to silver.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

The samples were filtered in the field and collected during dry and wet weather. The analyses for the metals were done as total dissolved metals.

QAPP Information:

The data is in compliance with the NPDES Permit's Monitoring and Reporting Program Requirements which include Quality Assurance provisions.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 99424, Silver	Region 8
San Diego Creek Reach 2

LOE ID:

82242

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Fixed station physical/chemical (conventional plus toxic pollutants)

Data Used to Assess Water Quality:

None of the five samples exceeded the water quality objective for silver.

Data Reference:

Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.

Objective/Criterion Reference:

Water Quality Control Plan, Santa Ana River Basin

Evaluation Guideline:

California Toxics Rule (CTR) lists criterion maximum concentrations for silver to protect aquatic life in freshwater (1-hour average). The disolved silver criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.

Guideline Reference:

Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition

Spatial Representation:

Samples were collected from San Diego Creek Reach 2 at Laguna Canyon Road, station LCRF05.

Temporal Representation:

Samples were collected on 10/5/06, 6/6/07, 10/10/07, 5/13/08 and 9/30/08.

Environmental Conditions:

Samples are representative of dry weather conditions.

QAPP Information:

Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.

QAPP Information Reference(s):


DECISION ID	77662	Region 8
San Diego Creek Reach 2

Pollutant:	Indicator Bacteria
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2021
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	While this Decision was based on a sufficient number of exceedances the of E. coli Single Sample objective, it should be noted that when representative 30-day, 5-sample Geomean values are collected the Single Sample E. coli LOE will be retired. No new data were assessed this cycle. The decision has not changed, and is presented in "Decision Relationships Continued". From 2010 Listing Cycle: USEPA Final Approval Decision Details: The November 12, 2010 USEPA partial approval letter and the October 11, 2011 final approval letter both from Alexis Strauss, USEPA Region 9, to Tom Howard, SWRCB, concluded the following: USEPA added San Diego Creek Reach 2 to the list of water quality limited segments requiring a TMDL for indicator bacteria. This water body is designated as a Water Contact Recreation (REC1) water body either explicitly or implicitly as tributaries to other designated segments (RWQCB Santa Ana Region, 2008, Table 3-1, pp.3-23 - 3-35). The Santa Ana Basin Plan has the following water quality objective for fecal coliform to protect REC1 beneficial use: Fecal coliform: log mean less than 200 organisms/100 mL based on five or more samples/30 day period, and not more than 10% of the samples exceed 400 organisms/100 mL for any 30-day period. (RWQCB Santa Ana Region, 2008, pp.4-9) Recent monitoring data collected in this water body measures Escherichia coli (E. coli) indicator bacteria. E. coli is one species within the broader category of fecal coliform bacteria and monitoring data for E. coli can be used to evaluate whether the fecal coliform objective is being met in the subject water body. In addition, USEPA has recommended that California use USEPA's Ambient Water Quality Criteria for Bacteria (1986) when there is no adopted E. coli standard. Specifically, USEPA recommends that for REC1 beneficial use the following criteria be used: Steady state geometric mean indicator density - 126 indicator densities/100ml Designated beach area (upper 75% confidence limit) - 235 indicator densities/100ml (EPA, 1986, Table 4, pp.15) USEPA compared the E. coli data for this water body to the Basin Plan's fecal coliform objective, as well as to USEPA's recommended E. coli criteria and the results were: 1. Thirty-one of the 64 samples taken exceeded the USEPA E. coli criteria (235 organisms/100ml). 2. Twenty-eight of the 64 samples taken exceeded the Basin Plan objective for fecal coliform (400 organisms/100ml). For this water body segment, sufficient exceedances of the fecal coliform objective and the USEPA recommended criteria exist to merit listings per the 10% exceedance threshold for conventional pollutants expressed in Table 3.2 of the State Listing Policy. For historical clarification, the Regional and State Water Board detailed decision recommendations made prior to USEPA's final decision are presented in their respective recommendation fields in this decision. Note: All lines of evidence (LOEs) previously made by the Regional Boards have been revised where necessary in accordance with USEPA's final decision.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current. The decision has not changed.

State Board Review of Regional Board Conclusion and Recommendation:	From 2010 Listing Cycle: USEPA Final Approval Decision Details: The November 12, 2010 USEPA partial approval letter and the October 11, 2011 final approval letter both from Alexis Strauss, USEPA Region 9, to Tom Howard, SWRCB, concluded the following: USEPA added San Diego Creek Reach 2 to the list of water quality limited segments requiring a TMDL for indicator bacteria. This water body is designated as a Water Contact Recreation (REC1) water body either explicitly or implicitly as tributaries to other designated segments (RWQCB Santa Ana Region, 2008, Table 3-1, pp.3-23 - 3-35). The Santa Ana Basin Plan has the following water quality objective for fecal coliform to protect REC1 beneficial use: Fecal coliform: log mean less than 200 organisms/100 mL based on five or more samples/30 day period, and not more than 10% of the samples exceed 400 organisms/100 mL for any 30-day period. (RWQCB Santa Ana Region, 2008, pp.4-9) Recent monitoring data collected in this water body measures Escherichia coli (E. coli) indicator bacteria. E. coli is one species within the broader category of fecal coliform bacteria and monitoring data for E. coli can be used to evaluate whether the fecal coliform objective is being met in the subject water body. In addition, USEPA has recommended that California use USEPA's Ambient Water Quality Criteria for Bacteria (1986) when there is no adopted E. coli standard. Specifically, USEPA recommends that for REC1 beneficial use the following criteria be used: Steady state geometric mean indicator density - 126 indicator densities/100ml Designated beach area (upper 75% confidence limit) - 235 indicator densities/100ml (EPA, 1986, Table 4, pp.15) USEPA compared the E. coli data for this water body to the Basin Plan's fecal coliform objective, as well as to USEPA's recommended E. coli criteria and the results were: 1. Thirty-one of the 64 samples taken exceeded the USEPA E. coli criteria (235 organisms/100ml). 2. Twenty-eight of the 64 samples taken exceeded the Basin Plan objective for fecal coliform (400 organisms/100ml). For this water body segment, sufficient exceedances of the fecal coliform objective and the USEPA recommended criteria exist to merit listings per the 10% exceedance threshold for conventional pollutants expressed in Table 3.2 of the State Listing Policy. For historical clarification, the Regional and State Water Board detailed decision recommendations made prior to USEPA's final decision are presented in their respective recommendation fields in this decision. Note: All lines of evidence (LOEs) previously made by the Regional Boards have been revised where necessary in accordance with USEPA's final decision.

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 77662, Indicator Bacteria	Region 8
San Diego Creek Reach 2

LOE ID:

21554

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Of the 64 samples taken by Orange County Coast Keeper Coastal Watersheds Project, 31 exceeded USEPA's recommended single sample standard and 28 samples exceeded the Basin Plan fecal coliform objective.

Data Reference:

USEPA Partial Approval Disapproval Letter and enclosures for California's 2008-2010 303(d) List

USEPA Final Decision Letter with enclosures and responsiveness summary regarding waters added to California's 2008-2010 303(d) List

Orange County Coast Keeper Coastal Watersheds Project

USEPA Region 9 data summary for addition of indicator bacteria to California 2010 303(d) list for some Santa Ana River - Region 8 water bodies

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

USEPA Recommended Ambient Water Quality Criteria for Bacteria -1986: E. coli: log mean less than 126 organisms/100 mL based on five or more samples per 30-day period, and single sample shall not exceed 235 organisms/100mL.

Santa Ana Region Basin Plan objective for Fecal coliform: log mean less than 200 organisms/100 mL based on five or more samples/30 day period, and not more than 10% of the samples exceed 400 organisms/100 mL for any 30-day period. (RWQCB Santa Ana Region, 2008, pp.4-9)

Objective/Criterion Reference:

Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002

Objective/Criterion Reference:

Water Quality Control Plan for the Santa Ana River Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were taken at three locations: San Diego Creek 1, 2, 3, (sd1, sd2, and sd3).

sd1 - Bake Parkway: This site is located off of Irvine Center Drive on the right hand side before the Wild Rivers water park.

sd2 - 133 Fwy: The 133 Fwy is located off of Pacifica and Alton in the dead end down the ramp in the riverbed. This area is just downstream of SD1 Bake Parkway, yet has never been dry.

sd3 - Sand Canyon : The Sand Canyon site is located off of the 405 freeway at Sand Canyon avenue past Alton at the bridge on the northeast corner of Barranca and Sand Canyon avenue. There is a pullout with a chain gate.

Temporal Representation:

The samples were collected monthly starting on December 23, 2003, at sd1 and sd3, through June 21, 2004. Monthly samples were also collected at sd2 starting on October 22, 2002 through June 21, 2004.

Environmental Conditions:

Staff is not aware of any special conditions that might effect interpretation of the data.

QAPP Information:

The data's quality is deemed appropriate because it was obtained under the auspices of a QAPP approved by the Regional Board.

QAPP Information Reference(s):


DECISION ID	68051	Region 8
San Diego Creek Reach 2

Pollutant:	Nutrients
Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status	Original
Sources:	Agriculture \| Groundwater Loadings \| Urban Runoff/Storm Sewers
TMDL Name:	Newport Bay Watershed Nutrient TMDL
TMDL Project Code:	156
Date TMDL Approved by USEPA:	01/01/1999
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	There was no new data considered in the 2014 Listing Cycle, this previously made decision will carryover. The following description applies to an earlier Listing Cycle. This pollutant is being considered for listing under section 2.2 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status. The Newport Bay Watershed Nutrient TMDL was completed in 1999. This water segment-pollutant combination was moved off the section 303(d) list during the 2002 listing cycle. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination in the Water Quality Limited Segments Being Addressed portion of the section 303(d) list.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current. The decision has not changed.

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 68051, Nutrients	Region 8
San Diego Creek Reach 2

LOE ID:

2970

Pollutant:

Nutrients

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):


DECISION ID	68048	Region 8
San Diego Creek Reach 2

Pollutant:	Sedimentation/Siltation
Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status	Original
Sources:	Agriculture \| Channel Erosion \| Construction/Land Development \| Erosion/Siltation
TMDL Name:	Newport Bay Watershed Sediment TMDL
TMDL Project Code:	160
Date TMDL Approved by USEPA:	04/16/1999
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	There was no new data considered in the 2014 Listing Cycle, this previously made decision will carryover. The following description applies to an earlier Listing Cycle. This pollutant is being considered for listing under section 2.2 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status. The San Diego Creek - Reach 1/2 Sedimentation TMDL was completed in 1999. This water segment-pollutant combination was moved off the section 303(d) list during the 2002 listing cycle. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination in the Water Quality Limited Segments Being Addressed portion of the section 303(d) list.

Regional Board Decision Recommendation:	This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current. The decision has not changed.

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 68048, Sedimentation/Siltation	Region 8
San Diego Creek Reach 2

LOE ID:

2971

Pollutant:

Sedimentation/Siltation

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Not Recorded

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):