Final California 2010 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name: Paso Robles Creek
Water Body ID: CAR3098115620020124123533
Water Body Type: River & Stream
 
DECISION ID
14630
Region 3     
Paso Robles Creek
 
Pollutant: Electrical Conductivity
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 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.

One line of evidence is available in the administrative record to assess this pollutant. None of the 4 samples exceed the Agricultural Supply water quality objective.

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 the 4 samples exceed the Agricultural Supply water quality objective 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 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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 14630, Electrical Conductivity
Region 3     
Paso Robles Creek
 
LOE ID: 17533
 
Pollutant: Electrical Conductivity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Conductivity(Us).
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when conductivity exceeds 3.0 mS/cm in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
 
DECISION ID
14631
Region 3     
Paso Robles Creek
 
Pollutant: Escherichia coli (E. coli)
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 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.

Two line of evidence is available in the administrative record to assess this pollutant. One of the 3 samples exceed the Evaluation Guideline (USEPA Ambient Water Quality Criteria for Bacteria, 1986) as it applies to the Water Contact Recreation beneficial use.

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 3 samples exceed the Evaluation Guideline (USEPA Ambient Water Quality Criteria for Bacteria, 1986) as it applies to the Water Contact Recreation beneficial use 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 and the sample size is insufficient to determine with the power and confidence of the Listing Policy if water quality standards are met or exceeded.
 
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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 14631, Escherichia coli (E. coli)
Region 3     
Paso Robles Creek
 
LOE ID: 17520
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Escherichia coli.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 ml, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 ml. E. coli is a fecal coliform.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/1/2004-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 14631, Escherichia coli (E. coli)
Region 3     
Paso Robles Creek
 
LOE ID: 17519
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 1 of 3 samples exceed the criterion for Escherichia coli.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: USEPA Ambient Water Quality Criteria for Bacteria -1986.
Objective/Criterion Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Evaluation Guideline: Single sample maximum allowable density for E. coli in freshwater is 235 MPN/100mL (as stated in Table 4, page 15)
Guideline Reference: Ambient Water Quality Criteria for Bacteria - 1986. EPA440/5-84-002
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/1/2004-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
 
DECISION ID
14632
Region 3     
Paso Robles Creek
 
Pollutant: Fecal Coliform
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 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.

Two lines of evidence are available in the administrative record to assess this pollutant. The single sample did not exceed the Water contact Recreation water quality objective.

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. The single sample did not exceed the Water contact Recreation water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. In addition, the sample size is insufficient to determine with the power and confidence of the Listing Policy if water quality standards are met or exceeded.
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 and the sample size is insufficient to determine with the power and confidence of the Listing Policy if water quality standards are met or exceeded.
 
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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 14632, Fecal Coliform
Region 3     
Paso Robles Creek
 
LOE ID: 17621
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Coliform, Fecal.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 200 MPN/100 ml, nor shall more than ten percent of total samples during any 30-day period exceed 400 MPN/100 ml.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected on a single day 5/17/2003. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 14632, Fecal Coliform
Region 3     
Paso Robles Creek
 
LOE ID: 17622
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Coliform, Fecal.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 ml, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 ml.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected on a single day 5/17/2003. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
 
DECISION ID
14634
Region 3     
Paso Robles Creek
 
Pollutant: Low Dissolved Oxygen
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 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.

One line of evidence is available in the administrative record to assess this pollutant. One of the 4 samples exceed the Cold Freshwater Habitat water quality objective.

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 4 samples exceed the Cold Freshwater Habitat water quality objective 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 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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 14634, Low Dissolved Oxygen
Region 3     
Paso Robles Creek
 
LOE ID: 18033
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 1 of 4 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, Cold Water Habitat Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
 
DECISION ID
14633
Region 3     
Paso Robles Creek
 
Pollutant: Nitrate
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 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. None of the 4 samples exceed the water quality objectives for Municipal and Domestic Supply or for Agricultural Supply.

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 the 4 samples exceed the water quality objectives for Municipal and Domestic Supply or for Agricultural Supply 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 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 applicable water quality standards for the pollutant are not exceeded.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 14633, Nitrate
Region 3     
Paso Robles Creek
 
LOE ID: 18366
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Nitrate as N.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin Objective for municipal and domestic supply uses of inland surface waters (Section II.A.2) states the following: waters shall not contain concentrations of chemical constituents in excess of the limits specified in California Code of Regulations, Title 22, Article 4, Chapter 15, Section 64435, Tables 2 and 3 as listed in Table 3-2. The maximum contaminant level listed in Table 3-2 (inorganic and fluoride concentrations not to be exceeded in domestic or municipal supply) for nitrate is 10.0 mg/L (NO3 as N).
Objective/Criterion Reference: Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A
  Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 14633, Nitrate
Region 3     
Paso Robles Creek
 
LOE ID: 18286
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Nitrate as N.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when nitrate exceeds 30 mg/L NO3 as N in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
 
DECISION ID
14635
Region 3     
Paso Robles Creek
 
Pollutant: Temperature, water
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 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.

One line of evidence is available in the administrative record to assess this pollutant. None of the 4 samples exceed the Evaluation Guideline (Moyle 1976) applied to protect the Cold Freshwater Habitat beneficial use.

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 the 4 samples exceed the Evaluation Guideline (Moyle 1976) applied to protect the Cold Freshwater Habitat beneficial use 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 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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 14635, Temperature, water
Region 3     
Paso Robles Creek
 
LOE ID: 18781
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for Water Temperature.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: 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 (General Objective in Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).
Guideline Reference: Inland Fishes of California
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
 
DECISION ID
14636
Region 3     
Paso Robles Creek
 
Pollutant: Turbidity
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 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.

One line of evidence is available in the administrative record to assess this pollutant. None of the 3 samples exceed the Evaluation Guideline (Sigler et al., 1984) applied to protect for aquatic life beneficial uses.

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 the 3 samples exceed the Evaluation Guideline (Sigler et al., 1984) applied to protect for aquatic life beneficial uses 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 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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 14636, Turbidity
Region 3     
Paso Robles Creek
 
LOE ID: 18686
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/1/2004-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
 
DECISION ID
14637
Region 3     
Paso Robles Creek
 
Pollutant: pH
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the 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.

Five lines of evidence are available in the administrative record to assess this pollutant. One of the 4 samples exceed the Agricultural Supply water quality objective, None of the samples exceed the Cold Freshwater Habitat water quality objective and one of the 4 samples exceed the numeric objective for Municipal & Domestic Supply, Non-Contact Recreation and Water Contact Recreation.

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 4 samples exceed the Agricultural Supply water quality objective, None of the samples exceed the Cold Freshwater Habitat water quality objective and one of the 4 samples exceed the numeric objective for Municipal & Domestic Supply, Non-Contact Recreation and Water Contact Recreation.
None of these 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 and the sample size is insufficient to determine with the power and confidence of the Listing Policy if water quality standards are met or exceeded.
 
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.
 
USEPA Action (if applicable):
 
 
Line of Evidence (LOE) for Decision ID 14637, pH
Region 3     
Paso Robles Creek
 
LOE ID: 18127
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Agricultural Supply
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 1 of 4 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. Interpretation of adverse effect shall be as derived from the University of California Agricultural Extension Service guidelines provided in Table 3-3 (Central Coast Waterboard Basin Plan, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). In Table 3-3 of the Basin Plan (page III-8), water quality guidelines state that severe problems may occur when pH is greater than 8.4 or less than 6.5 in irrigation supply water.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 14637, pH
Region 3     
Paso Robles Creek
 
LOE ID: 18145
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 1 of 4 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 14637, pH
Region 3     
Paso Robles Creek
 
LOE ID: 18144
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 1 of 4 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 14637, pH
Region 3     
Paso Robles Creek
 
LOE ID: 18143
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 4
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 1 of 4 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin, Section II.A.2. Municipal and Domestic Supply Objectives, Section II.A.2.a states the following: The pH value shall neither be depressed below 6.5 or raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 14637, pH
Region 3     
Paso Robles Creek
 
LOE ID: 18142
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Coastal Watershed Council (Snapshot day monitoring) (R3_Snap) data for Paso Robles Creek to determine beneficial use support and results are as follows: 0 of 4 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Monterey Bay National Marine Sanctuary Volunteer Monitoring Network Data. 2003-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Paso Robles Creek was collected at 1 monitoring site [ 309-PASOR-41 - Paso Robles Creek at Santa Rita Rd]
Temporal Representation: Data was collected over the time period 5/17/2003-5/6/2006. Coastal Watershed Council Snapshot Day Monitoring is conducted annually.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: State Board approved QAPP. Multiple errors were identified in data and were flagged or fixed by RB staff (in communication with Project staff) prior to assessment of data.
QAPP Information Reference(s):