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

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name:	San Lorenzo Creek (Monterey County)
Water Body ID:	CAR3091800020020103133204
Water Body Type:	River & Stream


DECISION ID	125853	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Escherichia coli (E. coli)
Final Listing Decision:	Delist from 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status	Revised
Reason for Delisting:	Applicable WQS attained; due to change in WQS
TMDL Name:	San Lorenzo Creek FIB TMDL
TMDL Project Code:	1069
Date TMDL Approved by USEPA:	11/30/2011
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	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 greater than 1 part per thousand (ppt) 95 percent or more of the time, the enterococci bacteria objective applies, and the E. coli objective is not applicable. The 95th percentile of salinity samples from station 309LOR is 4.712 ppt (based on 29 samples) and therefore the E. coli water quality objective is not applicable for water contact recreation beneficial use support determination in this waterbody. Therefore, this waterbody is being considered for removal from the CWA section 303(d) List under section 4 of the Listing Policy due to a change in water quality standards. After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the CWA section 303(d) List because the E. coli bacteria water quality objective is not applicable.

Regional Board Decision Recommendation:	After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be removed from the CWA section 303(d) List because the water quality standard is not applicable for the pollutant, based on the salinity in this waterbody segment.

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 125853, Escherichia coli (E. coli)	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

10904

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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 San Lorenzo Creek (Monterey County) was collected at 2 monitoring sites [ 309LOK-San Lorenzo Creek at First Street in King City, 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/25/2006-12/11/2006. Salinas watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.

Environmental Conditions:

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

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission. All data are flagged as appropriate.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 125853, Escherichia coli (E. coli)	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51541

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Staff assessed public submissions data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Escherichia coli.

Data Reference:

Salinas Rotation field data 2007

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 of the USEPA Ambient Water Quality Criteria for Bacteria -1986).

Guideline Reference:

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

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 125853, Escherichia coli (E. coli)	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

148233

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Staff assessed public submissions data for San Lorenzo Creek to determine beneficial use support and results are as follows: 1 of 2 samples exceed the criterion for Escherichia coli.

Data Reference:

SWAMP FIB data: 1/4/2018--4/16/2018.

SWAMP Data:

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:

Data for this line of evidence for San Lorenzo Creek was collected at 1 monitoring site [309LOR]

Temporal Representation:

Data was collected on 2 sampling date(s): 04/24/2018 and 01/30/2018. CCAMP data is collected monthly and other samples associated with this project are included in another LOE for this site

Environmental Conditions:

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPrP. QA data are included in submission. All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 125853, Escherichia coli (E. coli)	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

150379

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for San Lorenzo Creek (Monterey County) to determine beneficial use support and the results are as follows: 2 of the 12 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:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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): 309LOR

Temporal Representation:

The samples were collected between the days of 2012-01-09 and 2018-12-18 .

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 125853, Escherichia coli (E. coli)	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

148232

Pollutant:

Escherichia coli (E. coli)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

SWAMP FIB data: 1/4/2018--4/16/2018.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective applicable to all non-saline waters, is a geometric mean (GM) of E. coli not to exceed 100 cfu/100 mL. The waterbody GM shall not be greater than the applicable GM magnitude in any six-week interval, calculated weekly (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:

Data for this line of evidence for San Lorenzo Creek was collected at 1 monitoring site [309LOR]

Temporal Representation:

Data was collected on 2 sampling date(s): 04/24/2018 and 01/30/2018. CCAMP data is collected monthly and other samples associated with this project are included in another LOE for this site

Environmental Conditions:

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAPrP. QA data are included in submission. All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	130242	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Fecal Coliform
Final Listing Decision:	Delist from 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status	Revised
Reason for Delisting:	Applicable WQS attained; due to change in WQS
TMDL Name:	San Lorenzo Creek FIB TMDL
TMDL Project Code:	1069
Date TMDL Approved by USEPA:	11/30/2011
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 of the Listing Policy due to a change in water quality standards. The State Water Boards 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: where the salinity level of a waterbody is equal to or less than 1 part per thousand 95 percent or more of the time, the E. coli bacteria objective applies; and where the salinity level of a waterbody is greater than 1 part per thousand 95 percent or more of the time, the Enterococci bacteria objective applies. These objectives supersede the fecal coliform water quality objective for water contact recreation. Consequently, the fecal coliform objective for water contact recreation is no longer applicable to this waterbody and those LOEs have been removed from this decision. Therefore, this waterbody is being removed from the CWA section 303(d) List under section 4 of the Listing Policy due to a change in water quality standards. However, three lines of evidence (LOEs) are available in the administrative record to assess this pollutant and the non-contact recreation use. Therefore, 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. Five of the 41 samples exceed the water quality objective for non-contact recreation. After review of the available data and information for the non-contact recreation beneficial use, RWQCB staff concludes that the water body-pollutant combination should not be placed on the CWA section 303(d) List because applicable water quality standards for the pollutant are not being exceeded. In accordance with section 2.2 of the Policy, there is sufficient justification to place it in the Being Addressed portion of the 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. Five of the 41 samples exceed the water quality objective for non-contact recreation, and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. The San Lorenzo Creek FIB TMDL has been approved by the USEPA on 11/30/2011. 5. 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 removed from the CWA section 303(d) List under section 4 of the Listing Policy due to a change in water quality standards. This water body pollutant combination should be placed 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.

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 130242, Fecal Coliform	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

150399

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed data for San Lorenzo Creek (Monterey County) to determine beneficial use support and the results are as follows: 0 of the 12 samples exceeded the water quality threshold for Coliform, Fecal. The water quality threshold is based on a 10% exceedance rate that is calculated for a 30-Day peroid.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section 3.3.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) 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 for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site(s), station(s): 309LOR

Temporal Representation:

The samples were collected between the days of 2012-01-09 and 2018-12-18 .

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 130242, Fecal Coliform	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51543

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

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:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 130242, Fecal Coliform	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

10888

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 2/2/1999-12/11/2006. Salinas watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	126397	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Specific Conductivity
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	No Source Analysis Available
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the Clean Water Act (CWA) section 303(d) List under section 4.2 of the Listing Policy. Under section 4.2 a single line of evidence is necessary to assess listing status. A total of five lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. Once summed, a total of 26 of 37 samples exceed the water quality objective for agricultural supply. Note that the pollutant name for the older LOEs is electrical conductivity. This was an error and the pollutant name should have always been specific conductivity. For this reason, all five of the LOEs are combined into this assessment for specific conductivity. 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. 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. A total of 26 of 37 samples exceed the water quality objective for agricultural supply and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

Regional Board Decision Recommendation:	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 126397, Specific Conductivity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

182671

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 7 of 7 samples exceeded the water quality threshold for SpecificConductivity.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

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 listed in the Central Coast Basin Plan and identified as the level at which severe problems may occur when EC exceeds 3.0 mmho/cm in irrigation supply water (meaurements reported at 25 degrees C). EC measured, at 25 degrees C , is referred to as specific conductivity. Also note that 1 mmho/cm = 1000 uS/cm.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-05-29 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 126397, Specific Conductivity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51581

Pollutant:

Specific Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Staff assessed public submissions data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 2 of 2 samples exceed the criterion for Conductivity(Us).

Data Reference:

Salinas Rotation field data 2007

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 3000 uS/cm in irrigation supply water.

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 126397, Specific Conductivity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

10889

Pollutant:

Electrical Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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:

Temporal Representation:

Data was collected over the time period 12/2/1999-12/11/2006. Salinas watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 126397, Specific Conductivity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

10924

Pollutant:

Electrical Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Conductivity(Us).

Data Reference:

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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 San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected on a single day 7/28/1999. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 126397, Specific Conductivity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

13868

Pollutant:

Electrical Conductivity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed Central Coast Watershed Studies (R3_CCOWS) data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 7 of 13 samples exceed the criterion for Conductivity(Us).

Data Reference:

Final Data File used for assessment: CCoWS (Central Coast Watershed Studies) Water Quality Data

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 San Lorenzo Creek (Monterey County) was collected at 2 monitoring sites [ No bridge, Bitterwater Rd (USGS stn), First Street (G15, King City)]

Temporal Representation:

Data was collected over the time period 3/15/2000-3/6/2001.

Environmental Conditions:

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

QAPP Information:

Data quality is good and Standard Operating Procedures are well documented in QAPP. However, data documentation is poor and replicate samples and other quality assurance measurements are not consistently documented in this data set.

QAPP Information Reference(s):


DECISION ID	108426	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	pH
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status	Revised
Sources:	No Source Analysis Available
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the Clean Water Act section 303(d) List under sections 4.2 of the Listing Policy. Under this section, a single line of evidence is necessary to assess listing status. Fifteen lines of evidence are available in the administrative record to assess this pollutant. Nineteen of the 30 samples exceed the maximum pH water quality objective for Municipal and Domestic Supply, Contact and Non-contact Recreation beneficial uses. Eleven of the 30 samples exceed the maximum pH water quality objective for Warm Freshwater Habitat and 17 of 30 samples exceeded the Agriculture Supply objective. 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. 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. Nineteen of the 30 samples exceed the maximum pH water quality objective for Municipal and Domestic Supply, Contact and Non-contact Recreation beneficial uses, 11 of the 30 samples exceed the maximum pH water quality objective for Warm Freshwater Habitat and 17 of 30 samples exceeded the Agriculture Supply objective and this exceeds the allowable frequency listed in Table 4.2 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 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 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

178425

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 8 of 14 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

178436

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 3 of 14 samples exceeded the water quality threshold for pH.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan, Central Coast Basin objective for warm fresh water habitat (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 7.0 nor raised above 8.5.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

178426

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan, Central Coast Basin objective for water contact recreation (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

177986

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

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 listed in the Central Coast Basin Plan and identified as the level 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 for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51593

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

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 Region 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:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

10906

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51607

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Staff assessed public submissions data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 1 of 2 samples exceed the criterion for pH.

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH value shall not be depressed below 6.5 or raised above 8.3 (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

10907

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51544

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

10922

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

10923

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51572

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH value shall not be depressed below 7.0 or raised above 8.5 (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51542

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The pH value shall neither be depressed below 6.5 nor raised above 8.3 (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

10921

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 108426, pH	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

178040

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan, Central Coast Basin objective for municipal and domestic supply (Section 3.3.2 Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries) states that the pH value shall neither be depressed below 6.5 nor raised above 8.3.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108432	Region 3
San Lorenzo Creek (Monterey County)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 108432, Aluminum	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

233116

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Aluminum.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The National Recommended Water Quality Criteria for the protection of aquatic life from aluminum, expressed in terms of total recoverable metal in the water column, is the chronic continuous concentration (4-day average) of 87 ug/L.

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108432, Aluminum	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

157220

Pollutant:

Aluminum

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan and identified as the maximum concentration for aluminum for irrigation supply as 5.0 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	128044	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Ammonia
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. Seven lines of evidence (LOEs) are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. The following is a summary of the sample and exceedances for each beneficial use: Based on LOEs summarizing un-ionized ammonia data, zero of the 21 samples exceed the water quality objective (Basin Plan) set to protect aquatic life. Based on LOEs summarizing total ammonia data (‘nitrogen, ammonia’ and ‘nitrogen as ammonia’) zero of the 8 samples exceed the EPA's Aquatic Life Ambient Water Quality Criteria set to protect aquatic life. This sample size is insufficient to determine an applicable beneficial use support rating with the power and confidence of the Listing Policy. In accordance with Table 3.1 of the Listing Policy, a minimum of 16 samples is needed to determine if a beneficial use is fully supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported. Based on LOEs summarizing total ammonia data (‘nitrogen, ammonia’ and ‘nitrogen as ammonia’) zero of the 42 samples exceed the EPA's Lifetime Health advisory level set to protect municipal and domestic supply 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 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 samples exceed the water quality objectives 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 128044, Ammonia	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

9506

Pollutant:

Ammonia as Nitrogen

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

USEPA Health Advisory 2006 Edition of the Drinking Water Standards and Health Advisories (EPA 822-R-06-013, 2006).

Objective/Criterion Reference:

2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013

Evaluation Guideline:

EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2006 edition of the drinking water standards and health advisories. This Advisory Level is defined as "the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for up to ten days of exposure."

Guideline Reference:

2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013

Spatial Representation:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 128044, Ammonia	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51595

Pollutant:

Ammonia as Nitrogen

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

2006 edition of the drinking water standards and health advisories. EPA 822-R-03-013

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 128044, Ammonia	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

184243

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 13 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

EPA's Lifetime Health advisory level for total ammonia is 30.0 mg/L as stated on page 8 of the 2012 edition of the drinking water standards and health advisories. This Advisory Level is defined as 'the concentration of a chemical in drinking water that is not expected to cause any adverse noncarcinogenic effects for a lifetime of exposure.'

Guideline Reference:

2018 Edition of the Drinking Water Standards and Health Advisories

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 128044, Ammonia	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51555

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

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 that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 128044, Ammonia	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

219405

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the water quality threshold for Ammonia as N, Unionized. Although a total of 13 samples were collected, 8 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Coast Basin General Objective, Chapter 3, Section 3.3.2 (Objectives for all Inland Surface Waters, Enclosed Bays, and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/L (as N) in receiving waters (page 32).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-01-09 to 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 128044, Ammonia	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

9552

Pollutant:

Ammonia (Unionized)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 128044, Ammonia	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

183895

Pollutant:

Nitrogen, ammonia (Total Ammonia)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 8 samples exceeded the water quality threshold for Ammonia as N.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

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

Objective/Criterion Reference:

Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-02-07 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108417	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Arsenic
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 Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy. A total of two lines of evidence are available in the administrative record to assess this pollutant. A total of zero of one sample exceeds the water quality objective for the agricultural supply beneficial use and zero of one sample exceeds the evaluation guideline for the municipal and domestic supply beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence 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 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. A total of zero of one sample exceeds the water quality objective for the agricultural supply beneficial use and zero of one sample exceeds the evaluation guideline for the municipal and domestic supply beneficial use. 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. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 108417, Arsenic	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

158358

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108417, Arsenic	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

158227

Pollutant:

Arsenic

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Maximum Contaminant Level for Arsenic is 10 ug/L.

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108418	Region 3
San Lorenzo Creek (Monterey County)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 108418, Cadmium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

160077

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Maximum Contaminant Level for cadmium is 0.005 mg/L (California Code of Regulations, Title 22).

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108418, Cadmium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

159704

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108418, Cadmium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

160064

Pollutant:

Cadmium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion continuous concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108431	Region 3
San Lorenzo Creek (Monterey County)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 108431, Chromium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

161880

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108431, Chromium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

161786

Pollutant:

Chromium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Maximum Contaminant Level for total chromium is 0.05 mg/L (California Code of Regulations, Title 22).

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108420	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Copper
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 Clean Water Act (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. A total of three lines of evidence are available in the administrative record to assess this pollutant. A total of zero of 13 samples exceed the water quality objective for the agricultural supply beneficial use, zero of 13 samples exceed the water quality objective for the municipal and domestic supply beneficial use and zero of seven samples exceed the water quality objective for the warm freshwater habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy. After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed 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. A total of zero of 13 samples exceed the water quality objective for the agricultural supply beneficial use, zero of 13 samples exceed the water quality objective for the municipal and domestic supply beneficial use and zero of seven samples exceed the water quality objective for the warm freshwater habitat beneficial use. 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. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 108420, Copper	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

162032

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The Copper criteria for the protection of human health from the consumption of water and organisms is 1.300 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108420, Copper	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

162723

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108420, Copper	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

162968

Pollutant:

Copper

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and the results are as follows: 0 of the 7 samples exceeded the water quality threshold for Copper. Although a total of 13 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-01-09 to 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108421	Region 3
San Lorenzo Creek (Monterey County)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 108421, Lead	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

233318

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All inland surface waters, enclosed bays, and estuaries shall not contain concentrations of organic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Article 5.5, Section 64444, Table 64444-A.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Maximum Contaminant Level for lead is 15 ug/L (California Code of Regulations, Title 22).

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108421, Lead	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

167660

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108421, Lead	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

167725

Pollutant:

Lead

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108422	Region 3
San Lorenzo Creek (Monterey County)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 108422, Manganese	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

168988

Pollutant:

Manganese

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in the Central Coast Basin Plan identified as the maximum concentration for manganese for irrigation supply as 0.2 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108423	Region 3
San Lorenzo Creek (Monterey County)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 108423, Nickel	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

170896

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108423, Nickel	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

170806

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Commercial or recreational collection of fish, shellfish, or organisms

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Human health risk associated with organism consumption is 4.6 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108423, Nickel	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

170840

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain concentrations of inorganic chemicals in excess of the maximum contaminant levels for primary drinking water standards specified in California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431 and 64433.2 (Water Quality Control Plan, Central Coast Basin)

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The maximum contaminant level of nickel in public water systems shall be 0.1 mg/L (California Code of Regulations, Title 22, Division 4, Chapter 15, Sections 64431).

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108423, Nickel	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

170996

Pollutant:

Nickel

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	128137	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Nitrate
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. Sixteen lines of evidence are available in the administrative record to assess this pollutant. Lines of evidence for the pollutant name Nitrate and for the pollutant name Nitrogen, Nitrate are combined (same pollutant). Where the fraction is none or not recorded, staff assumed that the fraction is identical to that reported for pollutants of the same name, based on the analytical method. In these cases, sample and exceedance counts are summed for the purpose of making this decision. Zero of the 52 nitrate samples and Zero of the 8 nitrate/nitrite samples exceed the water quality objectives for the Agricultural Supply and Municipal and Domestic Supply beneficial uses. Zero of the ten nitrate samples exceed and zero of the eight nitrate/nitrite samples exceed evaluation guideline for the Warm Freshwater Habitat beneficial use. Many of these sample counts are insufficient to determine a beneficial use support rating for this waterbody-pollutant combination with the statistical power and confidence 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 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 samples exceed the water quality objectives 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 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51558

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Technical approach to develop nutrient numeric endpoints for California, Tetra Tech, June 2006. The Central Coast Region numeric target for maximum nitrate concentration is based on the Tetra Tech NNE (Nutrient Numeric Endpoint) Model and CCAMP data for 193 sites, monitored monthly for at least 1 year between January 1998 and December 2006. The model numeric target for aquatic life habitats in the Central Coast Region is 1.0 mg/L Nitrate as N.

Guideline Reference:

Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111

Guideline Reference:

Central Coast RegionTechnical Paper: Interpreting Narrative Objectives for Biostimulatory Substances for California Central Coast Waters. This method uses the Technical Approach for Developing California Nutrient Numeric Endpoints.

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51606

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrate + nitrite (as N) that is incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51583

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

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. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3-4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for nitrate + nitrite for livestock watering is 100 mg/L.

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51557

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Technical Approach to Develop Nutrient Numeric Endpoints for California. U.S. EPA Region IX. State Water Resources Control Board. 68-C-02-108-To-111

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51605

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The California Maximum Contaminant Level for nitrate (NO3 as N) incorporated by reference in the Basin Plan is 10.0 mg/L (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

13799

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed Central Coast Watershed Studies (R3_CCOWS) data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 10 samples exceed the criterion for Nitrate as N.

Data Reference:

Final Data File used for assessment: CCoWS (Central Coast Watershed Studies) Water Quality Data

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:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Objective/Criterion Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 2 monitoring sites [ No bridge, Bitterwater Rd (USGS stn), First Street (G15, King City)]

Temporal Representation:

Data was collected over the time period 1/10/2001-3/6/2001.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

9549

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Objective/Criterion Reference:

Title 22, Division 4, Ch. 15, Article 4, Section 64431, Table 64431-A

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51582

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

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:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

13798

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed Central Coast Watershed Studies (R3_CCOWS) data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 10 samples exceed the criterion for Nitrate as N.

Data Reference:

Final Data File used for assessment: CCoWS (Central Coast Watershed Studies) Water Quality Data

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 San Lorenzo Creek (Monterey County) was collected at 2 monitoring sites [ No bridge, Bitterwater Rd (USGS stn), First Street (G15, King City)]

Temporal Representation:

Data was collected over the time period 1/10/2001-3/6/2001.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

9548

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

173109

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Nitrate as N.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Maximum Contaminant Level for nitrate (as N) 10.0 mg/L (California Code of Regulations, Title 22).

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

172602

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and the results are as follows: 0 of the 8 samples exceeded the water quality threshold for Nitrate as N. Although a total of 12 samples were collected, 4 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (Water Quality Control Plan, Central Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR).

Temporal Representation:

Data for this waterbody was collected over the date range 2012-01-09 to 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

173128

Pollutant:

Nitrogen, Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

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 listed in the Central Coast Basin Plan and identified as the level 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 for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

171421

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 6 samples exceeded the water quality threshold for Nitrate + Nitrite as N.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2012-06-11

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

171521

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Maximum Contaminant Level for nitrate + nitrite (as N) is 10. mg/L (California Code of Regulations, Title 22).

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2012-06-11

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 128137, Nitrate	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

171625

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2012-06-11

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	130639	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Nitrogen, Nitrite
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 Clean Water Act (CWA) section 303(d) List under section 3.1 of the Listing Policy. A total of two lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “dissolved” are grouped together with those having the fraction “total”, based on the analytical method used. A total of zero of 15 samples exceed the water quality objective for the agricultural supply beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy. After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed 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. A total of zero of 15 samples exceed the water quality objective for the agricultural supply beneficial use. 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. 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 130639, Nitrogen, Nitrite	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

173486

Pollutant:

Nitrogen, Nitrite

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicalslisted in the Central Coast Basin Plan and identified as the maximum concentration for nitrite for livestock watering as 10 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 130639, Nitrogen, Nitrite	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51592

Pollutant:

Nitrogen, Nitrite

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

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. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3-4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for nitrite for livestock watering is 10 mg/L.

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	108425	Region 3
San Lorenzo Creek (Monterey County)

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:	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. Six lines of evidence are available in the administrative record to assess this pollutant. Zero of 16 samples exceed the water quality objective for fish spawning (Basin Plan). Zero of 44 samples exceed the water quality objective for warm freshwater habitat (Basin Plan). Note that there is no difference between samples fractions ‘dissolved’ and ‘total,’ therefore sample and exceedance counts will be summed for the purpose of this decision. Previous decisions (pre-2020) included dissolved oxygen saturation LOEs as ancillary evidence. This decision will no longer include dissolved oxygen saturation and these LOEs will be retired next cycle. 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. The data support the conclusion that the aquatic life beneficial use is fully supported. For fish spawning, the data is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. 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. No samples exceed the objective for fish spawning or warm freshwater habitat. These do 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 108425, Oxygen, Dissolved	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

13016

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Oxygen, Dissolved.

Data Reference:

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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, dissolved oxygen concentration shall not be reduced below 5.0 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 San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 7/2/1999-7/28/1999. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 108425, Oxygen, Dissolved	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51570

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 108425, Oxygen, Dissolved	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51545

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 108425, Oxygen, Dissolved	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

175083

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed SWAMP RWB3 CCAMP Salinas Rotation data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 14 samples exceeded the water quality threshold for Oxygen, Dissolved.

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108425, Oxygen, Dissolved	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

174897

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Fish Spawning

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time (Water Quality Control Plan, Central Coast Basin).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108425, Oxygen, Dissolved	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

12998

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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, dissolved oxygen concentration shall not be reduced below 5.0 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:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	108427	Region 3
San Lorenzo Creek (Monterey County)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 108427, Selenium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

180999

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

The criterion continuous concentration to protect aquatic life in freshwater is 0.005 mg/L (California Toxics Rule, 2000).

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108427, Selenium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

181157

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The California Maximum Contaminant Level for selenium is 0.05 mg/L (California Code of Regulations, Title 22).

Guideline Reference:

California MCLs - Title 17 and Title 22 documents for 2019 - California Regulations Related to Drinking Water

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108427, Selenium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

181050

Pollutant:

Selenium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108428	Region 3
San Lorenzo Creek (Monterey County)

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

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

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

State Board Review of Regional Board Conclusion and Recommendation:

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

Line of Evidence (LOE) for Decision ID 108428, Silver	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

181927

Pollutant:

Silver

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

California Toxics Rule (CTR) lists criterion maximum concentrations to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion.

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2018-12-18 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108430	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Zinc
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 Clean Water Act (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. A total of two lines of evidence are available in the administrative record to assess this pollutant. A total of zero of 13 samples exceed the water quality objective for the agricultural supply beneficial use and zero of 13 samples exceed the water quality objective for the warm freshwater habitat beneficial use. These data are insufficient to determine the applicable beneficial use support rating with the power and confidence required by the Listing Policy. After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed 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. A total of zero of 13 samples exceed the water quality objective for the agricultural supply beneficial use and zero of 13 samples exceed the water quality objective for the warm freshwater habitat beneficial use. 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. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:

Line of Evidence (LOE) for Decision ID 108430, Zinc	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

156688

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108430, Zinc	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

182819

Pollutant:

Zinc

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program


DECISION ID	108429	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Turbidity
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:	No Source Analysis Available
Expected TMDL Completion Date:	2035
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the Clean Water Act (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. A total of three lines of evidence are available in the administrative record to assess this pollutant. Sample and exceedance counts for the lines of evidence with the fraction identified as “none” or “not recorded” are grouped together with those having the fraction “total”, based on the analytical method used. Once summed, a total of six of 29 samples exceed the evaluation guideline for warm freshwater habitat (Shoup, D.E. and Wahl D.H., 2009) used to interpret the water quality objectives for the aquatic life beneficial use. 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. 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. A total of six of 29 samples exceed the evaluation guideline for warm freshwater habitat 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.

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 108429, Turbidity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

183043

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Total

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Field, Habitat, Sediment, Tissue, Toxicity, Water data for the 2020/2022 integrated report in Region 3.

SWAMP Data:

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).

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Turbidities of 40 NTU or greater can cause a reduced foraging efficiency and a shift in prey selection in piscivorous fish (largemouth bass) due to interference with their ability to find prey (Shoup, D.E. and Wahl D.H., 2009).

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

The samples were collected at 1 monitoring site (309LOR)

Temporal Representation:

The samples were collected between the dates of 2012-01-09 and 2018-12-18

Environmental Conditions:

QAPP Information:

SWAMP 2008, SWAMP 2017

QAPP Information Reference(s):

Quality Assurance Program Plans, Quality Assurance Project Plans, and Standard Operating Procedures for the SWAMP program

Line of Evidence (LOE) for Decision ID 108429, Turbidity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

13001

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 108429, Turbidity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51573

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses (Basin Plan).

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Turbidities of 40 NTU or greater can cause a reduction in piscivorous fish (largemouth bass) growth due to interference with their ability to find food (Shoup, D.E. and Wahl D.H., 2009).

Guideline Reference:

The Effects of Turbidity on Prey Selection by Piscivorous Largemouth Bass

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	68331	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Boron
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2027
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 this pollutant. All 25 samples exceed the water quality objective for agricultural uses. However, the water bearing formations in the watershed are Purisima and Aromas Red Sands. These formations contain CaCO3 and contribute to naturally elevated salt levels and pH in surface water. 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. All 25 samples exceed the water quality objective 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 68331, Boron	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

9550

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Waters shall not contain concentrations of chemical constituents in amounts which adversely affect the agricultural beneficial use. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3.4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for boron for irrigation supply is 0.75 mg/L.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 7/2/1999-12/11/2006. Salinas watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68331, Boron	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51569

Pollutant:

Boron

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

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. In addition, waters used for irrigation and livestock watering shall not exceed concentrations for those chemicals listed in Table 3-4 (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland and Surface Waters, Enclosed Bays and Estuaries). Table 3-4 (page III-9) lists the maximum concentration for boron for irrigation supply is 0.75 mg/L.

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	73159	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Chloride
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown \| Grazing-Related Sources \| Natural Sources
Expected TMDL Completion Date:	2027
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 4.2 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. Twenty-eight of the 29 samples exceed the water quality objective for agricultural uses. However, the water bearing formations in the watershed are Purisima and Aromas Red Sands. These formations contain CaCO3 and contribute to naturally elevated salt levels and pH in surface water. 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. Twenty-eight of the 29 samples exceed the water quality objective and this exceeds the allowable frequency listed in Table 4.2 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 73159, Chloride	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

9507

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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 chloride exceeds 106 mg/L in irrigation supply water.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 73159, Chloride	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51580

Pollutant:

Chloride

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

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 chloride exceeds 106 mg/L in irrigation supply water.

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	73216	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Sodium
Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Do Not Delist from 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2027
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 4.2 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. All 25 samples exceed the water quality objective for agricultural uses. However, the water bearing formations in the watershed are Purisima and Aromas Red Sands. These formations contain CaCO3 and contribute to naturally elevated salt levels and pH in surface water. 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. All 25 samples exceed the water quality objective and this exceeds the allowable frequency listed in Table 4.2 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 73216, Sodium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51594

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

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 sodium exceeds 69 mg/L in irrigation supply water.

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Line of Evidence (LOE) for Decision ID 73216, Sodium	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

9551

Pollutant:

Sodium

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Agricultural Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

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 sodium exceeds 69 mg/L in irrigation supply water.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):


DECISION ID	108419	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Chlorophyll-a
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	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	No new data were assessed for the 2020 listing cycle. 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. Four of the 26 samples exceed the evaluation guideline (North Carolina Administrative code, Title 15A) used to interpret the narrative water quality objective for bio-stimulation risk and 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 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 the 26 samples exceed the evaluation guideline 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 108419, Chlorophyll-a	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

9508

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Objective/Criterion Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Objective/Criterion Reference:

Water quality standards table

Evaluation Guideline:

North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Spatial Representation:

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 108419, Chlorophyll-a	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

51556

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Salinas Rotation field data 2007

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Data for Various Pollutants in Westside San Joaquin Water Quality Coalition, 2004-2009.

Evaluation Guideline:

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Guideline Reference:

North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards

Guideline Reference:

Water quality standards table

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 1/9/2007-2/13/2007.

Environmental Conditions:

Central Coast Water Board Staff are not aware of any special conditions that might affect interpretation of the data.

QAPP Information:

All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). All data are flagged as appropriate.

QAPP Information Reference(s):

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)


DECISION ID	87013	Region 3
San Lorenzo Creek (Monterey County)

Pollutant:	Toxicity
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:	No new data were assessed. This pollutant is being considered for placement on the section 303(d) list under section 3.1 and section 3.6 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day and time at the same location. Three LOEs summarize water samples. Two water samples are summarized in LOEs using each of the test organisms as the pollutant name (i.e. plant toxicity, invertebrate toxicity or vertebrate toxicity). Zero of the two water samples resulted in a significant toxic effect to one or more test organisms. This sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples is needed to determine if a beneficial use is supported and a minimum of two exceedances is needed to determine if beneficial uses are not supported using table 3.1. Therefore, the use support rating is set to '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 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 samples were toxic to test organisms and therefore do not exceed the narrative General Objective for toxicity, set to protect for aquatic life beneficial uses 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 87013, Toxicity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

24415

Pollutant:

Vertebrate Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCAMP Salinas (Salinas) data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Toxicity, Cyprinodon variegatus Survival (%) 7 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which 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, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (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:

Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.

Guideline Reference:

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Data was collected over the time period 6/14/2006-2/13/2007. Salinas watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 87013, Toxicity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

24426

Pollutant:

Plant Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCAMP Salinas (Salinas) data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Toxicity, Thalassiosira Growth (Cell Density) 4 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Significant reduction in cell count of test organism relative to the control (alpha < 0.05) and cell count <80% of control.

Guideline Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 87013, Toxicity	Region 3
San Lorenzo Creek (Monterey County)

LOE ID:

24425

Pollutant:

Invertebrate Toxicity

LOE Subgroup:

Toxicity

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

TOXICITY TESTING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed CCAMP Salinas (Salinas) data for San Lorenzo Creek (Monterey County) to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Toxicity, Hyalella azteca sediment 10-day survival %. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).

Data Reference:

Final Data File used for assessment: CCAMP Salinas Toxicity data

Final Data File used for assessment: CCAMP Water Quality Data_file1

Final Data File used for assessment: CCAMP Water Quality Data_file2

Final Data File used for assessment: CCAMP Water Quality Data_file3

SWAMP Data:

SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)

Evaluation Guideline:

Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.

Guideline Reference:

Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)

Spatial Representation:

Data for this line of evidence for San Lorenzo Creek (Monterey County) was collected at 1 monitoring site [ 309LOR-San Lorenzo Creek at Bitterwater Road east of King City]

Temporal Representation:

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):