Draft California 2020 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 9 - San Diego Region

Water Body Name: Encinitas Creek
Water Body ID: CAR9045100019991117144759
Water Body Type: River & Stream
 
DECISION ID
111637
Region 9     
Encinitas Creek
 
Pollutant: Phosphorus
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: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA 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.

Two lines of evidence are available in the administrative record to assess pollutant. Fourteen of the 47 samples exceed the threshold.

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.

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. Fourteen of 47 samples exceeded the threshold, and this exceeds 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 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: 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 111637, Phosphorus
Region 9     
Encinitas Creek
 
LOE ID: 3193
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Four water samples, 4 samples exceeding (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growth causes nuisances or adversely affects beneficial uses.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/l in stream and flowing waters.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station at Encinitas Creek: 33.06828 -117.26261
Temporal Representation: Samples were collected from March through September of 2002.
Environmental Conditions: San Marcos Creek Watershed 904.51.
QAPP Information: SWAMP Quality Assurance Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 111637, Phosphorus
Region 9     
Encinitas Creek
 
LOE ID: 145893
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 43
Number of Exceedances: 10
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Encinitas Creek to determine beneficial use support and results are as follows: 10 of 43 samples exceeded the water quality threshold for Phosphorus as P.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (BTQ-010)
Temporal Representation: The samples were collected between the dates of 2010-09-11 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
 
DECISION ID
127854
Region 9     
Encinitas Creek
 
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: 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 of the 38 samples exceed the water quality threshold.

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 38 samples exceed the water quality threshold, 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:
 
 
Line of Evidence (LOE) for Decision ID 127854, Ammonia
Region 9     
Encinitas Creek
 
LOE ID: 185113
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 38
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Encinitas Creek to determine beneficial use support and results are as follows: 0 of 38 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-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 (BTQ-010)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
 
DECISION ID
115509
Region 9     
Encinitas Creek
 
Pollutant: Ammonia (Unionized)
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.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 39 samples exceed the water quality threshold.

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 39 samples exceeded the threshold 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 115509, Ammonia (Unionized)
Region 9     
Encinitas Creek
 
LOE ID: 185288
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 38
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Encinitas Creek to determine beneficial use support and results are as follows: 0 of 38 samples exceeded the water quality threshold for Ammonia as N, Unionized.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (BTQ-010)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 115509, Ammonia (Unionized)
Region 9     
Encinitas Creek
 
LOE ID: 73526
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: 0 of 1 samples exceed the water objective for un-ionized ammonia (NH3) at 0.025 mg/l (as N). Un-ionized ammonia (as N) was calculated from Total Ammonia (as N) from monthly samples reported in the data. The calculated un-ionized ammonia (as N) values was then established and compared to the un-ionized Ammonia (as N) at 0.025 mg/L in the RB9 Basin Plan.
Data Reference: Statewide Perennial Streams Assessment 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, San Diego Region (SDRWQCB 2007): All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. The discharge of wastes shall not cause concentrations of un-ionized ammonia (NH3) to exceed 0.025 mg/l (as N) in inland surface waters, enclosed bays and estuaries and coastal lagoons.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at 904PS0034 (Encinitas Creek).
Temporal Representation: Samples collected on 5/13/2008.
Environmental Conditions:
QAPP Information: SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
 
DECISION ID
111635
Region 9     
Encinitas Creek
 
Pollutant: Oxygen, Dissolved
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 111635, Oxygen, Dissolved
Region 9     
Encinitas Creek
 
LOE ID: 144459
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Encinitas Creek to determine beneficial use support and results are as follows: 2 of 11 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with the WARM beneficial use designated (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (BTQ-010)
Temporal Representation: The samples were collected between the dates of 2016-07-16 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111635, Oxygen, Dissolved
Region 9     
Encinitas Creek
 
LOE ID: 73527
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The sample collected exceeded the objective.
Data Reference: Statewide Perennial Streams Assessment 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Dissolved oxygen levels shall not be less than 5.0 mg/l in inland surface waters with designated MAR or WARM beneficial uses. The annual mean dissolved oxygen concentration shall not be less than 7 mg/l more than 10% of the time.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: One sample was collected from the 904PS0034 station.
Temporal Representation: One sample was collected in May 2008.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s):
 
 
DECISION ID
111638
Region 9     
Encinitas Creek
 
Pollutant: Turbidity
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: Region 9 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

One line of evidence is available in the administrative record to assess this pollutant. A single sample was collected and it did not exceed the Basin Plan criteria, but the number of samples is insufficient to determine with the confidence and power required by the Listing Policy.

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 section 303(d) list in the Water Quality Limited Segments category.
 
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 111638, Turbidity
Region 9     
Encinitas Creek
 
LOE ID: 147869
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 29
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Encinitas Creek to determine beneficial use support and results are as follows: 1 of 29 samples exceeded the water quality threshold for Turbidity.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Turbidity water quality threshold in this HSA is 20 NTU, and this level is not to be exceeded more than 10% of the time during any one year period (Basin Plan, Table 3-2).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (BTQ-010)
Temporal Representation: The samples were collected between the dates of 2011-05-21 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
Line of Evidence (LOE) for Decision ID 111638, Turbidity
Region 9     
Encinitas Creek
 
LOE ID: 3190
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by RWQCB9 in 1998. One sample was collected and was not in exceedance. (SWRCB, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters and all beneficial uses, the WQO for turbidity is 20 ntu. This concentration is not to be exceeded more than 10% of the time during any one year period.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Encinitas Creek at Green Valley Rd.
Temporal Representation: Samples were collected on 06/03/1998.
Environmental Conditions:
QAPP Information: Data used in 2002 assessment.
QAPP Information Reference(s):
 
 
DECISION ID
111636
Region 9     
Encinitas Creek
 
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: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2, a single line of evidence is necessary to assess listing status. Two line(s) of evidence are available in the administrative record to assess this pollutant. One of the 41 samples exceeds the water quality threshold. 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. One of 41 samples exceeded the water quality threshold, and this does not exceed the allowable frequency listed in Table 3.2 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 111636, pH
Region 9     
Encinitas Creek
 
LOE ID: 73528
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Numeric data generated from 1 sample collected had no exceedences.
Data Reference: Statewide Perennial Streams Assessment 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: In inland surface waters[,] the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the 904PS0034 station.
Temporal Representation: One sample was collected in May 2008
Environmental Conditions:
QAPP Information: SWAMP QAPP
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 111636, pH
Region 9     
Encinitas Creek
 
LOE ID: 145235
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 40
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Encinitas Creek to determine beneficial use support and results are as follows: 1 of 40 samples exceeded the water quality threshold for pH.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: In inland surface waters the pH shall not be depressed below 6.5 nor raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (BTQ-010)
Temporal Representation: The samples were collected between the dates of 2010-11-20 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
 
DECISION ID
127874
Region 9     
Encinitas Creek
 
Pollutant: Indicator Bacteria
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2033
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 3.3 of the Listing Policy. Under section 3.3 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. Eight of the 41 samples exceed the STV threshold for E. coli.

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 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. Eight of 41 samples exceed the E. coli water quality threshold for the protection of REC-1, and this exceeds the allowable frequency listed in Table 3.2 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.

The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the E. coli objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

For E. coli data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
 
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.
 
State Board Review of Regional Board Conclusion and Recommendation: The State Water Board’s Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California (the “ISWEBE Plan”) contains two bacteria water quality objectives applicable to the REC-1 beneficial use, which were adopted on August 7, 2018. Because the salinity level of this waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies Therefore, this waterbody is being considered for placement on or removal from the CWA section 303(d) List under section 3.3 or 4.3 of the Listing Policy, as applicable, using the E. coli objective.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

For E. coli data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

No fecal coliform data are used in this assessment because the fecal coliform water quality objective was superseded and is no longer used as the basis of any 303(d) List decision for water contact recreation.
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 127874, Indicator Bacteria
Region 9     
Encinitas Creek
 
LOE ID: 220612
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 41
Number of Exceedances: 8
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed data for Encinitas Creek to determine beneficial use support and the results are as follows: 8 of the 41 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective applicable to all non-saline waters, is a Statistical Threshold Value (STV) of 320 cfu/100 mL. The applicable STV shall not be exceeded by more than 10 percent of the samples collected in a calendar month, calculated in a static manner (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): BTQ-010
Temporal Representation: The samples were collected between the days of 2010-09-11 and 2018-10-06 .
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
 
DECISION ID
127595
Region 9     
Encinitas Creek
 
Pollutant: Nitrogen
Final Listing Decision: 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
Sources: A Source Unknown
Expected TMDL Completion Date: 2033
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. Thirty of the 48 samples exceed the water quality threshold.

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 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. Thirty of the 48 samples exceed the water quality threshold, and this exceeds 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 be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
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 127595, Nitrogen
Region 9     
Encinitas Creek
 
LOE ID: 6526
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Two of four samples collected at Encinitas Creek show excessive nitrogen concentrations according to results in California's Surface Water Ambient Monitoring Program Report, 2007.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses (RWQCB, 2007). A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total phosphorus, P. These values are not to be exceeded more than 10% of the time unless studies of the specific water body in question clearly show that water quality objective changes are permissible and changes are approved by the Regional Board. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Water samples were collected at Encinitas Creek station 2, 904CBENC2; (Latitude 33.06824, Longitude -117.262515)
Temporal Representation: Water samples were collected in March, April, June and September 2002.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 127595, Nitrogen
Region 9     
Encinitas Creek
 
LOE ID: 143792
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 44
Number of Exceedances: 28
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed San Diego Coastkeeper Ambient Monitoring Program data for Encinitas Creek to determine beneficial use support and results are as follows: 28 of 44 samples exceeded the water quality threshold for Nitrogen, Total.
Data Reference: Water data for the 2020/2022 integrated report in Region 9.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Concentrations of nitrogen and phosphorus, by themselves or in combination with other nutrients, shall be maintained at levels below those which stimulate algae and emergent plant growth. A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total P. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (Water Quality Control Plan, San Diego Basin).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site (BTQ-010)
Temporal Representation: The samples were collected between the dates of 2010-09-11 and 2018-10-06
Environmental Conditions:
QAPP Information: San Diego Coastkeeper. 2010. San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan.
QAPP Information Reference(s): San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan
 
 
DECISION ID
68403
Region 9     
Encinitas Creek
 
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: Region 9 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

This pollutant is being considered for placement on the 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.

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 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. None of 4 samples exceeded the CDFG Aquatic Life Hazard Assessment Criteria 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: 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 cycle. 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 68403, Diazinon
Region 9     
Encinitas Creek
 
LOE ID: 3194
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Of the four water samples, none of the samples were exceeding. (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: No individual pesticides or combination of pesticides shall be present in the water column, sediments, or biota at concentrations that adversely affect beneficial uses.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: CDFG Aquatic Life Hazard Assessment Criteria 1-hour averave 0.16 ug/L (Siepman & Finlayson, 2000; Finlayson, 2004).
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station at Encinitas Creek: 33.06828 -117.26261.
Temporal Representation: Samples were collected from March through September of 2002.
Environmental Conditions: San Marcos Creek Watershed 904.51.
QAPP Information: SWAMP Quality Assurance Plan.
QAPP Information Reference(s):
 
 
DECISION ID
82190
Region 9     
Encinitas Creek
 
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)(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 3.2 of the Listing Policy. Under section 3.2 a single line(s) of evidence are necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero of 0 samples exceeds the 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 of 0 samples exceeds the 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 26 samples is needed to determine if a beneficial use is fully supported using table 3.2.
4. Pursuant to section 3.2 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 82190, Temperature, water
Region 9     
Encinitas Creek
 
LOE ID: 72837
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Nine samples total were collected however there is no evaluation guideline for assessing temperature for the warm freshwater beneficial use.
Data Reference: Data for Trash, Nutrients, and Pathogens in Region 9, 2007-2010.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (Water Quality Control Plan San Diego Basin - Region 9).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at station BTQ-010 (Levante St. Bridge (south side)).
Temporal Representation: Samples were collected between January, 2009 and July, 2010.
Environmental Conditions:
QAPP Information: "San Diego Regional Water Quality Assessment and Outreach Project Quality Assurance Project Plan Prepared by: Clay Clifton (San Diego Coastkeeper, Local Project Sponsor Manager), Bob Stafford (San Diego Stream Team), Dr. Rick Gersberg (San Diego State University), Bryan Bjorndal (Assure Controls, Inc.), and Morgan Justice-Black (I Love A Clean San Diego)."
QAPP Information Reference(s): Quality Assurance Project Plan for San Diego Regional Water Quality Assessment and Outreach Project.
 
 
DECISION ID
68851
Region 9     
Encinitas Creek
 
Pollutant: Total Dissolved Solids
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: Region 9 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

One line of evidence is available in the administrative record to assess this pollutant. A single sample was collected and it did exceed the Basin Plan criteria, but the number of samples is insufficient to determine with the confidence and power required by the Listing Policy.

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 section 303(d) list in the Water Quality Limited Segments category.
 
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 cycle. 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 68851, Total Dissolved Solids
Region 9     
Encinitas Creek
 
LOE ID: 3189
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Unknown
Fraction: Total
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data were collected by RWQCB9 in 1998. One sample was collected, it was in exceedance. (SWRCB, 2003).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan: For inland surface waters and all beneficial uses, the WQO for TDS is 500 mg/L. This concentration is not to be exceeded more than 10% of the time during any one year period.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Encinitas Creek at Green Valley Road.
Temporal Representation: Samples were collected on 06/03/1998.
Environmental Conditions:
QAPP Information: Data used in 2002 assessment.
QAPP Information Reference(s):
 
 
DECISION ID
77663
Region 9     
Encinitas Creek
 
Pollutant: Benthic Community Effects
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: 2025
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.

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 exhibits significant degradation in biological populations and/or communities as compared to reference site(s) using the California Stream Condition Index.
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.
 
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(s) contributes to or causes the problem.
 
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 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 3191
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Data were collected for the San Diego Water Quality Control Board 1999 Biological Assessment Annual Report. Physical habitat scores for EC-GVR ranged from 104 to 116, moderate compared to other sampled waterbodies. BMI scores at EC-GVR were all below average. (SDRWQCB, 1999a).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Encinitas Creek, 5 riffles downstream of Green Valley Road (EC-GVR).
Temporal Representation: Samples were collected in May, September, November 1998 and May 1999.
Environmental Conditions:
QAPP Information: Data used in 2002 assessment.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 26716
 
Pollutant: Benthic Community Effects
LOE Subgroup: Adverse Biological Responses
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Three samples of IBI data were taken from May 2001 to May 2002 at one sampling site. All three samples exceeded the IBI impairment threshold.
Data Reference: Stream Bioassessment Data. Co-permitee Data. Collected 2002-2007
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the San Diego Basin Plan the objective is: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The Index of Biological Integrity (IBI) is an analytical tool that can be used to assess the biological and physical condition of streams and rivers within a zero to one hundred scoring range: Very Poor 0-19, Poor 20-39, Fair 40-59, Good 60- 79, Very Good 80-100. The IBI score of 39 was set as an impairment threshold because it is a statistical criterion of two standard deviations below the mean reference site score which defines the boundary between 'fair' and 'poor' IBI creek conditions. (Ode, p. 9)
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 one site: ENC-GVR on Encinitas Creek.
Temporal Representation: Sampling occurred during May and October in 2001 and on May 2002.
Environmental Conditions:
QAPP Information: Quality Control for collection and identification was conducted in accordance with the Quality Assurance Manual for Freshwater Bioassessment.
QAPP Information Reference(s): Quality Assurance Manual for Freshwater Bioassessment Revision 0
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 26383
 
Pollutant: Benthic Community Effects
LOE Subgroup: Adverse Biological Responses
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 7
Number of Exceedances: 7
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Seven samples of IBI data were taken from May 1998 to May 2000 at two sampling sites. All seven of the samples exceeded the IBI impairment threshold.
Data Reference: Fish and Game IBI Data
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: From the San Diego Basin Plan the objective is: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: The Index of Biological Integrity (IBI) is an analytical tool that can be used to assess the biological and physical condition of streams and rivers within a zero to one hundred scoring range: Very Poor 0-19, Poor 20-39, Fair 40-59, Good 60- 79, Very Good 80-100. The IBI score of 39 was set as an impairment threshold because it is a statistical criterion of two standard deviations below the mean reference site score which defines the boundary between 'fair' and 'poor' IBI creek conditions. (Ode, p. 9)
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 two sites: 904ENCGVR and 904ENCRSF on Encinitas Creek.
Temporal Representation: Sampling occurred during one to three events from May 1998 to May 2000.
Environmental Conditions:
QAPP Information: Quality Control for collection and identification was conducted in accordance with the Quality Assurance Project Plan for the California Stream Bioassessment Procedure and the State of California, California Monitoring an Assessment Program: "CMAP", Quality Assurance Project Plan.
QAPP Information Reference(s): The San Diego Stream Team Quality Assurance Project Plan
QAPP Information Reference(s): Quality Assurance Project Plan for the California Stream Bioassessment Procedure
QAPP Information Reference(s): State of California, California Monitoring and Assessment Program: "CMAP".
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 21383
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Four samples were collected at Encinitas Creek station 904CBENC2 from March 2002 to September 2002. The samples showed significant toxicity levels (SL) in the following tests: Selenastrum algae growth test - one of the four samples was toxic. Ceriodaphnia dubia survival/reproductive test - three of the four samples showed toxicity. The tests results can be found in California's Surface Water Ambient Monitoring Program Report, 2007. Samples were collected in March, April, June and September 2002.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: According to SWAMP, waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold (EPA, 2002).
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: Water Toxicity Samples were collected at Encinitas Creek station 2 (904CBENC2); (Latitude 33.0682, Longitude -117.2625).
Temporal Representation: Samples were collected in March, April, June and September 2002.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 6526
 
Pollutant: Total Nitrogen as N
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: Two of four samples collected at Encinitas Creek show excessive nitrogen concentrations according to results in California's Surface Water Ambient Monitoring Program Report, 2007.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water bodies shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growths cause nuisance or adversely affect beneficial uses (RWQCB, 2007). A desired goal in order to prevent plant nuisance in streams and other flowing waters appears to be 0.1 mg/L total phosphorus, P. These values are not to be exceeded more than 10% of the time unless studies of the specific water body in question clearly show that water quality objective changes are permissible and changes are approved by the Regional Board. Analogous threshold values have not been set for nitrogen compounds; however, natural ratios of nitrogen to phosphorus are to be determined by surveillance and monitoring and upheld. If data are lacking, a ratio of N:P = 10:1, on a weight to weight basis shall be used (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline:
Guideline Reference: Water Quality Control Plan for the San Diego Basin
 
Spatial Representation: Water samples were collected at Encinitas Creek station 2, 904CBENC2; (Latitude 33.06824, Longitude -117.262515)
Temporal Representation: Water samples were collected in March, April, June and September 2002.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 6523
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: All four samples collected at Encinitas Creek show excessive selenium concentrations according to results in California's Surface Water Ambient Monitoring Program Report, 2007. Samples were collected in March, April, June and September 2002.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic
substances in concentrations that are toxic to, or
that produce detrimental physiological responses
in human, plant, animal, or aquatic life (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: CTR Freshwater Chronic (CCC) 5 ug/L. (U.S. EPA, 2000).
Guideline Reference: Water Quality Standards; Establishment of Numeric Criteria for Priority Toxic Pollutants for the State of California; Rule. 40 CFR Part 131. U.S. Environmental Protection Agency, Region IX, Water Division, San Francisco, CA
 
Spatial Representation: Water samples were collected at Encinitas Creek station 2, 904CBENC2; (Latitude 33.06824, Longitude -117.262515).
Temporal Representation: Samples were collected in March, April, June and September 2002.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 26382
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Four samples were collected at Encinitas Creek station 904CBENC2 from March 2002 to September 2002. The samples showed significant toxicity levels (SL) in the following test: Hyalella azteca sediment toxicity. Two of four samples exhibited toxicity. The tests results can be found in California's Surface Water Ambient Monitoring Program Report, 2007. Samples were collected in March, April, June and September 2002.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: According to SWAMP, waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold (EPA, 2002).
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: Water Toxicity Samples were collected at Encinitas Creek station 2 (904CBENC2); (Latitude 33.0682, Longitude -117.2625).
Temporal Representation: Samples were collected in March, April, June and September 2002.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 3193
 
Pollutant: Phosphorus
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Four water samples, 4 samples exceeding (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growth to the extent that such growth causes nuisances or adversely affects beneficial uses.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: Water Quality Control Plan for the San Diego Basin Goal of 0.1 mg/l in stream and flowing waters.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station at Encinitas Creek: 33.06828 -117.26261
Temporal Representation: Samples were collected from March through September of 2002.
Environmental Conditions: San Marcos Creek Watershed 904.51.
QAPP Information: SWAMP Quality Assurance Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 79516
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Four samples were collected from two sites on Encinitas Creek. All four samples were below the 0.79 threshold, and therefore exceeding the water quality objective for the aquatic life beneficial use.
Data Reference: Data for Various Pollutants from the County of San Diego Copermittees Receiving Waters Monitoring and Reporting Program, 2001-2008.
  Statewide Perennial Streams Assessment 2008
  Region 9 CSCI Scores & Water Body Information
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego 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 (Rhen, 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: The samples were collected at station 904ENC-GVR and 904PS0034 on Encinitas Creek.
Temporal Representation: The samples were collected from 2001 to 2008.
Environmental Conditions:
QAPP Information: Samples were collected for the Statewide Perennial Streams Assessment 2008 following SWAMP protocols and by the County of San Diego NPDES MS4 Copermittees Receiving Waters Monitoring and Reporting Program
QAPP Information Reference(s): Quality Assurance Project Plan for SWAMP Bioassessment and Freshwater Bioassessment.
QAPP Information Reference(s): Statewide Perennial Streams Assessment 2008
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 72790
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: The one sample collected had an IBI score below 40. The IBI score was 0.
Data Reference: Statewide Perennial Streams Assessment 2008
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego 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: Development of a Benthic Index of Biotic Integrity (B-IBI) for Wadeable Streams in Northern Coastal California and its Application to Regional 305(b) Assessment
 
Spatial Representation: The samples were collected from Encinitas Creek.
Temporal Representation: The sample was collected in May 2008.
Environmental Conditions:
QAPP Information: Samples were collected for the Statewide Perennial Streams Assessment 2008 following SWAMP protocols and stored in the SWAMP database.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 72762
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Three of the three samples collected had an IBI score below 40. tr11c NPDES bioassessment
Data Reference: Data for Various Pollutants from the County of San Diego Copermittees Receiving Waters Monitoring and Reporting Program, 2001-2008.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration or other appropriate methods as specified by the State or Regional Board. Region 9 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego 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: Development of a Benthic Index of Biotic Integrity (B-IBI) for Wadeable Streams in Northern Coastal California and its Application to Regional 305(b) Assessment
 
Spatial Representation: The samples were collected at station ENC-GVR on Encinitas Creek.
Temporal Representation: The samples were collected in May and October 2001 and May 2002.
Environmental Conditions:
QAPP Information: The data was collected under the Southern California Regional Watershed Monitoring Program Bioassessment Quality Assurance Project Plan, June 25, 2009.
QAPP Information Reference(s): Quality Assurance Project Plan for SWAMP Bioassessment and Freshwater Bioassessment.
 
Line of Evidence (LOE) for Decision ID 77663, Benthic Community Effects
Region 9     
Encinitas Creek
 
LOE ID: 3192
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Data were collected by the Stream Team in 1999. Taxa richness was 5. There were 0 EPT taxa. Tolerance value was 2.9. Feeding groups were 64.3% collectors and 7.1% predators. Other feeding groups were not reported. (Stream Team, 2001).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at Encinitas Creek. Exact sampling location was not reported.
Temporal Representation: Samples were collected in the Fall of 1999.
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
 
DECISION ID
77043
Region 9     
Encinitas Creek
 
Pollutant: Selenium
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: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA 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.

One line of evidence is available in the administrative record to assess pollutant. Four of the four samples exceed the GUIDELINE.

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.

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 four samples exceeded the GUIDELINE and this exceeds 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 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 cycle. 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 77043, Selenium
Region 9     
Encinitas Creek
 
LOE ID: 6523
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical monitoring (conventional pollutants only)
Data Used to Assess Water Quality: All four samples collected at Encinitas Creek show excessive selenium concentrations according to results in California's Surface Water Ambient Monitoring Program Report, 2007. Samples were collected in March, April, June and September 2002.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic
substances in concentrations that are toxic to, or
that produce detrimental physiological responses
in human, plant, animal, or aquatic life (RWQCB, 2007).
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: CTR Freshwater Chronic (CCC) 5 ug/L. (U.S. EPA, 2000).
Guideline Reference: Water Quality Standards; Establishment of Numeric Criteria for Priority Toxic Pollutants for the State of California; Rule. 40 CFR Part 131. U.S. Environmental Protection Agency, Region IX, Water Division, San Francisco, CA
 
Spatial Representation: Water samples were collected at Encinitas Creek station 2, 904CBENC2; (Latitude 33.06824, Longitude -117.262515).
Temporal Representation: Samples were collected in March, April, June and September 2002.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
 
DECISION ID
76999
Region 9     
Encinitas Creek
 
Pollutant: Toxicity
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: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.6 of the Listing Policy. Under section 3.6 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. Five of the eight samples exceed the water quality objective for toxicity.

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 on the 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 eight samples exceed the Basin Plan objective for tocixity and this exceeds 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: 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 cycle. 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 76999, Toxicity
Region 9     
Encinitas Creek
 
LOE ID: 26382
 
Pollutant: Sediment Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Four samples were collected at Encinitas Creek station 904CBENC2 from March 2002 to September 2002. The samples showed significant toxicity levels (SL) in the following test: Hyalella azteca sediment toxicity. Two of four samples exhibited toxicity. The tests results can be found in California's Surface Water Ambient Monitoring Program Report, 2007. Samples were collected in March, April, June and September 2002.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: According to SWAMP, waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold (EPA, 2002).
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: Water Toxicity Samples were collected at Encinitas Creek station 2 (904CBENC2); (Latitude 33.0682, Longitude -117.2625).
Temporal Representation: Samples were collected in March, April, June and September 2002.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA
 
Line of Evidence (LOE) for Decision ID 76999, Toxicity
Region 9     
Encinitas Creek
 
LOE ID: 21383
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 3
 
Data and Information Type: Ambient toxicity testing (chronic)
Data Used to Assess Water Quality: Four samples were collected at Encinitas Creek station 904CBENC2 from March 2002 to September 2002. The samples showed significant toxicity levels (SL) in the following tests: Selenastrum algae growth test - one of the four samples was toxic. Ceriodaphnia dubia survival/reproductive test - three of the four samples showed toxicity. The tests results can be found in California's Surface Water Ambient Monitoring Program Report, 2007. Samples were collected in March, April, June and September 2002.
Data Reference: Monitoring data for Region 9
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: From the Basin Plan, all waters shall be free of toxic substances that are toxic to, or that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: Water Quality Control Plan for the San Diego Basin
 
Evaluation Guideline: According to SWAMP, waters are considered toxic when samples show significant toxicity levels (SWAMP code ¿SL¿) when compared to a negative control. Significant toxicity is determined when statistical tests result in an alpha of less than 5% and percent control values less than the evaluation threshold (EPA, 2002).
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: Water Toxicity Samples were collected at Encinitas Creek station 2 (904CBENC2); (Latitude 33.0682, Longitude -117.2625).
Temporal Representation: Samples were collected in March, April, June and September 2002.
Environmental Conditions:
QAPP Information: Quality control for the chemical analysis portion of this study was conducted in accordance with the California's Surface Water Ambient Monitoring Program.
QAPP Information Reference(s): 2002. Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. California Department of Fish and Game, Monterey, CA