Final California 2014 and 2016 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name: Shingle Mill Creek
Water Body ID: CAR3041202219980827102347
Water Body Type: River & Stream
 
DECISION ID
34448
Region 3     
Shingle Mill Creek
 
Pollutant: Sedimentation/Siltation
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2012)
Revision Status Revised
Sources: Channel Erosion | Erosion/Siltation | Highway/Road/Bridge Runoff | Road Construction
TMDL Name: San Lorenzo River Sediment
TMDL Project Code: 243
Date TMDL Approved by USEPA: 02/19/2004
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 4.9 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 this pollutant. The initial decision to place this water body segment-pollutant combination on the 303(d) list was made prior to 2006 and associated data and documentation are not held in an assessment database. As a result, there are no data associated with the LOE that is a placeholder for the original decision to add this water body segment/pollutant combination to the List. However, recent physical habitat and benthic invertebrate community data have been collected and are summarized in one LOE. The single sample did not have degraded biological community composition (EPT taxa richness less than 12) but did have more than 40 percent cover of deposited fine and sand sized sediment on the streambed.

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. The single sample did have more than 40 percent cover of deposited fine and sand sized sediment on the streambed. This supports the previous decision to add this water body segment/pollutant combination to the List.
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 34448, Sedimentation/Siltation
Region 3     
Shingle Mill Creek
 
LOE ID: 1842
 
Pollutant: Sedimentation/Siltation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Fish Spawning
 
Number of Samples:
Number of Exceedances:
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 34448, Sedimentation/Siltation
Region 3     
Shingle Mill Creek
 
LOE ID: 95257
 
Pollutant: Sediment
LOE Subgroup: Population/Community Degradation
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: BIOLOGICAL MONITORING
Data Used to Assess Water Quality: Water Board staff evaluated sediment grain size and EPT taxa data that was collected following the SWAMP physical habitat and benthic invertebrate protocol from Shingle Mill Creek. At one of the one stations, deposited fine and sand (FS) sediments on the stream bed were greater than 40%. However this sample had 14 EPT taxa, slightly more than 12 EPT taxa which is the threshold indicating degraded biological diversity and community composition at these locations.
Data Reference: Three papers summarizing numeric TMDL targets for benthic invertebrates and sediment indicators in the San Lorenzo River Watershed
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Central Coast Water Quality Control Plan (Basin Plan) general water quality objective. Waters shall not contain settable material in concentrations that result in deposition of material that cause nuisance or adversely affects beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan for the Central Coastal Basin
 
Evaluation Guideline: Loss of benthic invertebrate species diversity and altered community composition (based on the number of mayfly, stonefly and caddisfly taxa or EPT taxa richness) occurs when deposited fine and sand (FS) sediments on the stream bed exceeds 40% relative to Central Coast reference stream species composition and diversity (Herbst, D.B., et al, 2014 and Herbst, D.B., et al, 2011).
Guideline Reference: Three papers summarizing numeric TMDL targets for benthic invertebrates and sediment indicators in the San Lorenzo River Watershed
 
Spatial Representation: One monitoring location: Above Hwy 9 (2008).
Temporal Representation: Samples were collected in the spring - early season of 2007, 2008 and 2009
Environmental Conditions: None
QAPP Information: SWAMP protocols were followed for sample collection. SWAMP QAPP was followed.
QAPP Information Reference(s):
 
 
DECISION ID
37496
Region 3     
Shingle Mill Creek
 
Pollutant: Nitrate
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2012)
Revision Status Original
Sources: Agriculture | Collection System Failure | Natural Sources | Onsite Wastewater Systems (Septic Tanks) | Urban Runoff/Storm Sewers
TMDL Name: San Lorenzo River Nitrate
TMDL Project Code: 519
Date TMDL Approved by USEPA: 01/14/2003
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: No new data were assessed. The pollutant name was changed from the generic category of 'Nutrients' to 'Nitrate'.

This pollutant is being considered for removal from the section 303(d) list under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

A TMDL was approved by USEPA on January 14, 2003. The RWQCB is tracking the implementation of the TMDL through the Nitrate Management Plan being implemented by Santa Cruz County.

Three lines of evidence (LOEs) are available in the administrative record to assess this pollutant. One LOE (LOE #1841) is a placeholder that does not contain data or information. Staff are unable to reconstruct the original data used to place this water segment-pollutant combination on the section 303(d) list. A second LOE (#18640) contains all data evaluated for this assessment and compares that data to the Municipal and Domestic Supply Objective. None of the 110 samples exceed this objective (10 mg/L NO3 as N). The third LOE (#25223) assessed this same data, compared to the numeric target established by the TMDL. The numeric target meets the criteria of the Listing Policy (Section 6.1.3) as it is applicable to the beneficial use, protective of the beneficial use, linked to the pollutant under consideration, scientifically based and peer reviewed, well described and identified a range above which negative impacts will occur. Ninety-eight of 110 samples exceed the Evaluation Guideline (the numeric target from the TMDL, 2000).

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 section 303(d) list. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Ninety-eight of 110 samples exceed the Evaluation Guideline (the numeric target from the TMDL, 2000) and this exceeds the allowable frequency calculated from the equation 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 37496, Nitrate
Region 3     
Shingle Mill Creek
 
LOE ID: 1841
 
Pollutant: Nutrients
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 37496, Nitrate
Region 3     
Shingle Mill Creek
 
LOE ID: 18640
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 110
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Santa Cruz County Environmental Health Monitoring Program (R3_SCCEH) data for Shingle Mill Creek to determine beneficial use support and results are as follows: 0 of 110 samples exceed the criterion for Nitrate as N.
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1971-1996
  Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
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 Shingle Mill Creek was collected at 1 monitoring site [ 304SHM_SCC - SHINGLE MILL CR. at SLR]
Temporal Representation: Data was collected over the time period 3/19/1996-7/13/2006.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: This monitoring program has been underway for thirty years, with changes over time to protocols, level of QA, and documentation. In general, QA documentation included with the dataset is minimal. However, data quality appears to be reasonably good.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 37496, Nitrate
Region 3     
Shingle Mill Creek
 
LOE ID: 26448
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 103
Number of Exceedances: 98
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data collected by Santa Cruz County Environmental Health staff from the Shingle Mill Creek at confluence with San Lorenzo River are assessed relative to the numeric target for Nitrate, established by Resolution number 00-003 adopting the TMDL for nitrate in the San Lorenzo River Watershed. 98 of 103 samples exceed the numeric target.
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin has the following narrative General Objective: Waters shall not contain taste or odor-producing substances in concentrations that impart undesirable tastes or odors to fish flesh or other edible products of aquatic origin, that cause nuisance, or that adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Resolution number 00-003 adopting the TMDL for nitrate in the San Lorenzo River Watershed (specifically including Shingle Mill Creek) established the following numeric target for Nitrate: 1.5 mg/L Nitrate as NO3 (or 0.33 mg/L Nitrate as N).
Guideline Reference: San Lorenzo River Nitrate TMDL
 
Spatial Representation: Data were collected by Santa Cruz County Environmental Health staff from the Shingle Mill Creek at confluence with San Lorenzo River (304SHM).
Temporal Representation: Santa Cruz County Environmental Health staff conducted monitoring at Shingle Mill Creek at confluence with San Lorenzo River between January 1997 and August 2006.
Environmental Conditions:
QAPP Information: Santa Cruz County Environmental Health monitoring program QA.
QAPP Information Reference(s):
 
 
DECISION ID
37357
Region 3     
Shingle Mill 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)(2012)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: No new data were assessed.

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 lines of evidence are available in the administrative record to assess this pollutant. One of the 107 samples exceeded the water quality objective for dissolved oxygen in Cold Freshwater Habitats. The Basin Plan general water quality objective for oxygen saturation states that the median value shall not fall below 85% saturation. However, the oxygen saturation objective is only applied ?for waters not mentioned by a specific beneficial use?? and this water body is designated for Cold Freshwater Habitats. Therefore, the use support rating for oxygen saturation is set at Insufficient Information.

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 the 107 samples exceeded the 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: 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 37357, Oxygen, Dissolved
Region 3     
Shingle Mill Creek
 
LOE ID: 19910
 
Pollutant: Dissolved oxygen saturation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 17
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Santa Cruz County Environmental Health Monitoring Program (R3_SCCEH) data for Shingle Mill Creek to determine beneficial use support and results are as follows: 1 of 17 samples exceed the criterion for Oxygen, Saturation.
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1971-1996
  Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
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: Median values should not fall below 85% saturation as a result of controllable water quality conditions.
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 Shingle Mill Creek was collected at 1 monitoring site [ 304SHM_SCC - SHINGLE MILL CR. at SLR]
Temporal Representation: Data was collected over the time period 12/13/1995-5/27/1998.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: This monitoring program has been underway for thirty years, with changes over time to protocols, level of QA, and documentation. In general, QA documentation included with the dataset is minimal. However, data quality appears to be reasonably good.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 37357, Oxygen, Dissolved
Region 3     
Shingle Mill Creek
 
LOE ID: 19835
 
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: 107
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Santa Cruz County Environmental Health Monitoring Program (R3_SCCEH) data for Shingle Mill Creek to determine beneficial use support and results are as follows: 1 of 107 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1971-1996
  Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
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 Shingle Mill Creek was collected at 1 monitoring site [ 304SHM_SCC - SHINGLE MILL CR. at SLR]
Temporal Representation: Data was collected over the time period 12/13/1995-7/13/2006.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: This monitoring program has been underway for thirty years, with changes over time to protocols, level of QA, and documentation. In general, QA documentation included with the dataset is minimal. However, data quality appears to be reasonably good.
QAPP Information Reference(s):
 
 
DECISION ID
37411
Region 3     
Shingle Mill 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)(2012)
Revision Status Original
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 113 samples exceed the Evaluation Guideline (Moyle 1976) applied to protect the Cold Freshwater Habitat beneficial use.

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 113 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: 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 37411, Temperature, water
Region 3     
Shingle Mill Creek
 
LOE ID: 19917
 
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: 113
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Santa Cruz County Environmental Health Monitoring Program (R3_SCCEH) data for Shingle Mill Creek to determine beneficial use support and results are as follows: 0 of 113 samples exceed the criterion for Water Temperature.
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1971-1996
  Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
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 Shingle Mill Creek was collected at 1 monitoring site [ 304SHM_SCC - SHINGLE MILL CR. at SLR]
Temporal Representation: Data was collected over the time period 12/13/1995-7/13/2006.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: This monitoring program has been underway for thirty years, with changes over time to protocols, level of QA, and documentation. In general, QA documentation included with the dataset is minimal. However, data quality appears to be reasonably good.
QAPP Information Reference(s):
 
 
DECISION ID
37533
Region 3     
Shingle Mill 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)(2012)
Revision Status Original
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 97 samples exceed the Evaluation Guideline (Sigler et al., 1984) applied to protect for aquatic life beneficial uses.

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 97 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: 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 37533, Turbidity
Region 3     
Shingle Mill Creek
 
LOE ID: 19667
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 97
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Santa Cruz County Environmental Health Monitoring Program (R3_SCCEH) data for Shingle Mill Creek to determine beneficial use support and results are as follows: 0 of 97 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1971-1996
  Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
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 Shingle Mill Creek was collected at 1 monitoring site [ 304SHM_SCC - SHINGLE MILL CR. at SLR]
Temporal Representation: Data was collected over the time period 12/13/1995-7/13/2006.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: This monitoring program has been underway for thirty years, with changes over time to protocols, level of QA, and documentation. In general, QA documentation included with the dataset is minimal. However, data quality appears to be reasonably good.
QAPP Information Reference(s):
 
 
DECISION ID
37546
Region 3     
Shingle Mill 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)(2012)
Revision Status Original
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.

Four lines of evidence are available in the administrative record to assess this pollutant. One of the 112 samples exceed the Cold Freshwater Habitat water quality objective and 3 of 112 samples exceed the numeric objective for Municipal & Domestic Supply, Non-Contact Recreation and Water Contact Recreation.

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. One of the 112 samples exceed the Cold Freshwater Habitat water quality objective and 3 of 112 samples exceed the numeric objective for Municipal & Domestic Supply, Non-Contact Recreation and Water Contact Recreation and 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: 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 37546, pH
Region 3     
Shingle Mill Creek
 
LOE ID: 19780
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 112
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Santa Cruz County Environmental Health Monitoring Program (R3_SCCEH) data for Shingle Mill Creek to determine beneficial use support and results are as follows: 3 of 112 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1971-1996
  Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
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 Shingle Mill Creek was collected at 1 monitoring site [ 304SHM_SCC - SHINGLE MILL CR. at SLR]
Temporal Representation: Data was collected over the time period 12/13/1995-7/13/2006.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: This monitoring program has been underway for thirty years, with changes over time to protocols, level of QA, and documentation. In general, QA documentation included with the dataset is minimal. However, data quality appears to be reasonably good.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 37546, pH
Region 3     
Shingle Mill Creek
 
LOE ID: 19796
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 112
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Santa Cruz County Environmental Health Monitoring Program (R3_SCCEH) data for Shingle Mill Creek to determine beneficial use support and results are as follows: 3 of 112 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1971-1996
  Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
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 Shingle Mill Creek was collected at 1 monitoring site [ 304SHM_SCC - SHINGLE MILL CR. at SLR]
Temporal Representation: Data was collected over the time period 12/13/1995-7/13/2006.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: This monitoring program has been underway for thirty years, with changes over time to protocols, level of QA, and documentation. In general, QA documentation included with the dataset is minimal. However, data quality appears to be reasonably good.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 37546, pH
Region 3     
Shingle Mill Creek
 
LOE ID: 19781
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 112
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Santa Cruz County Environmental Health Monitoring Program (R3_SCCEH) data for Shingle Mill Creek to determine beneficial use support and results are as follows: 3 of 112 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1971-1996
  Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
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 Shingle Mill Creek was collected at 1 monitoring site [ 304SHM_SCC - SHINGLE MILL CR. at SLR]
Temporal Representation: Data was collected over the time period 12/13/1995-7/13/2006.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: This monitoring program has been underway for thirty years, with changes over time to protocols, level of QA, and documentation. In general, QA documentation included with the dataset is minimal. However, data quality appears to be reasonably good.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 37546, pH
Region 3     
Shingle Mill Creek
 
LOE ID: 19779
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Cold Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat
 
Number of Samples: 112
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed Santa Cruz County Environmental Health Monitoring Program (R3_SCCEH) data for Shingle Mill Creek to determine beneficial use support and results are as follows: 1 of 112 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: Santa Cruz County Environmental Health data 1971-1996
  Final Data File used for assessment: Santa Cruz County Environmental Health data 1997-2006
 
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 Shingle Mill Creek was collected at 1 monitoring site [ 304SHM_SCC - SHINGLE MILL CR. at SLR]
Temporal Representation: Data was collected over the time period 12/13/1995-7/13/2006.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
QAPP Information: This monitoring program has been underway for thirty years, with changes over time to protocols, level of QA, and documentation. In general, QA documentation included with the dataset is minimal. However, data quality appears to be reasonably good.
QAPP Information Reference(s):