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

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name:	Bennett Slough
Water Body ID:	CAR3060001420080611160605
Water Body Type:	River & Stream


DECISION ID	72421	Region 3
Bennett Slough

Pollutant:	Chlorophyll-a
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:	2018
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the 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. Six lines of evidence are available in the administrative record to assess this pollutant. Forty-eight of the 234 samples exceed the evaluation guideline used to interpret the narrative water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list. 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. Forty-eight of the 234 samples exceed the evaluation guideline used to interpret the narrative 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 72421, Chlorophyll-a	Region 3
Bennett Slough

LOE ID:

15224

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

153

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed National Estuarine Research Reserve Monitoring Program (R3_ESNERR) data for Bennett Slough to determine beneficial use support and results are as follows: 35 of 153 samples exceed the criterion for Chlorophyll a.

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

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 (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).

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:

Data for this line of evidence for Bennett Slough was collected at 5 monitoring sites [ 306BENEH1 - Bennett Slough, East, 305BENSTP - GoMoss Landing, 306BENWH1 - Bennett Slough, West, 306BENJTR - Jetty Road, 306MSLSKL - Skipper's Landing]

Temporal Representation:

Data was collected over the time period 7/31/2001-10/10/2006.

Environmental Conditions:

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

QAPP Information:

QAPP was adopted for work conducted since 2005. Prior to 2005 no QAPP was in place and data entry was completed by volunteers. Multiple errors were identified in data and were flagged by RB staff (in communication with Elkhorn Slough Program staff) prior to assessment of data.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 72421, Chlorophyll-a	Region 3
Bennett Slough

LOE ID:

15225

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:

153

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-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:

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:

Data was collected over the time period 7/31/2001-10/10/2006.

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 72421, Chlorophyll-a	Region 3
Bennett Slough

LOE ID:

52814

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Central Coast Water Board Staff assessed public submissions data for Bennett Slough to determine beneficial use support and results are as follows: 3 of 53 samples exceed the criterion for Chlorophyll a (lab).

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

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 Bennett Slough was collected at 4 monitoring sites [ 306BENEH1 - Bennett Slough East of Highway 1 , 306BENWH1 - Bennett Slough West of Highway 1 , 306BENJTR - Bennett Slough at Jetty Road , 305BENSTP - Bennett Slough at Struve Pond ]

Temporal Representation:

Data was collected over the time period 6/3/2008-7/7/2009.

Environmental Conditions:

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

QAPP Information:

Data was collected following the Quality Assurance Project Plan for Elkhorn Slough National Estuarine Research Reserve's Volunteer Monthly Water Quality Program. Replicate data were identified in data and were qualified by RB Central Coast Water Board S

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 72421, Chlorophyll-a	Region 3
Bennett Slough

LOE ID:

52922

Pollutant:

Chlorophyll-a

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Central Coast Water Board Staff assessed public submissions data for Bennett Slough to determine beneficial use support and results are as follows: 10 of 28 samples exceed the criterion for Chlorophyll a.

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

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:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 72421, Chlorophyll-a	Region 3
Bennett Slough

LOE ID:

52821

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:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

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:

Temporal Representation:

Data was collected over the time period 6/3/2008-7/7/2009.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 72421, Chlorophyll-a	Region 3
Bennett Slough

LOE ID:

52929

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:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

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:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3


DECISION ID	71858	Region 3
Bennett Slough

Pollutant:	Oxygen, Dissolved
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:	2018
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the 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. Ten lines of evidence are available in the administrative record to assess this pollutant. Low dissolved oxygen in impacting two of the three aquatic life beneficial uses. Two hundred twenty six of 822 samples exceed the Cold Freshwater Habitat water quality objective for dissolved oxygen, and nine of 28 samples are exceed the Estuarine Habitat beneficial uses. However, 99 of the 822 samples exceed the Warm Freshwater Habitat water quality objective and this does not exceed the allowable frequency in the Listing policy and so the use support rating for dissolved oxygen and the Warm Freshwater Habitat use is set at ¿fully supporting¿. The Basin Plan general water quality objective for oxygen saturation states that the median value shall not fall below 85% saturation. Furthermore, the oxygen saturation objective is only applied ¿for waters not mentioned by a specific beneficial use¿¿ and this water body is designated for both Cold and Warm Freshwater Habitats, and Estuarine Habitats. Therefore, the use support rating for oxygen saturation is set at Insufficient Information. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two hundred twenty six of 822 samples exceed the Cold Freshwater Habitat water quality objective for dissolved oxygen, nine of 28 sample are exceed the Estuarine Habitat and these exceed 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 71858, Oxygen, Dissolved	Region 3
Bennett Slough

LOE ID:

52899

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:

Central Coast Water Board Central Coast Water Board Staff assessed public submissions data for Bennett Slough to determine beneficial use support and results are as follows: 5 of 28 samples exceed the criterion for Oxygen, Dissolved.

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 71858, Oxygen, Dissolved	Region 3
Bennett Slough

LOE ID:

15308

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:

794

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed National Estuarine Research Reserve Monitoring Program (R3_ESNERR) data for Bennett Slough to determine beneficial use support and results are as follows: 94 of 794 samples exceed the criterion for Oxygen, Dissolved.

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, 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 Bennett Slough was collected at 5 monitoring sites [ 306MSLSKL - Skipper's Landing, 305BENSTP - GoMoss Landing, 306BENJTR - Jetty Road, 306BENWH1 - Bennett Slough, West, 306BENEH1 - Bennett Slough, East]

Temporal Representation:

Data was collected over the time period 1/20/1990-10/10/2006.

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 71858, Oxygen, Dissolved	Region 3
Bennett Slough

LOE ID:

52883

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Central Coast Water Board Staff assessed public submissions data for Bennett Slough to determine beneficial use support and results are as follows: 9 of 28 samples exceed the criterion for Oxygen, Dissolved.

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 71858, Oxygen, Dissolved	Region 3
Bennett Slough

LOE ID:

15307

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

794

Number of Exceedances:

217

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed National Estuarine Research Reserve Monitoring Program (R3_ESNERR) data for Bennett Slough to determine beneficial use support and results are as follows: 217 of 794 samples exceed the criterion for Oxygen, Dissolved.

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Coast Basin, Cold Water Habitat Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: The dissolved oxygen concentration shall not be reduced below 7.0 mg/l at any time.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/20/1990-10/10/2006.

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 71858, Oxygen, Dissolved	Region 3
Bennett Slough

LOE ID:

52860

Pollutant:

Oxygen, Dissolved

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3


DECISION ID	72146	Region 3
Bennett Slough

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)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2018
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for removal from the 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. Eight lines of evidence are available in the administrative record to assess this pollutant. Four beneficial uses are assessed. Three-hundred-twelve of the 884 samples exceed the water quality objectives for Cold and Warm Freshwater Habitats and 422 of the 884 samples exceed the water quality objectives for Recreation. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list. 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. Three-hundred-twelve of the 884 samples exceed the water quality objectives for Cold and Warm Freshwater Habitats and 422 of the 884 samples exceed the water quality objectives for Recreation and these 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 72146, pH	Region 3
Bennett Slough

LOE ID:

52901

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Central Coast Water Board Staff assessed public submissions data for Bennett Slough to determine beneficial use support and results are as follows: 15 of 28 samples exceed the criterion for pH.

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 72146, pH	Region 3
Bennett Slough

LOE ID:

15155

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

856

Number of Exceedances:

297

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/20/1990-10/10/2006.

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 72146, pH	Region 3
Bennett Slough

LOE ID:

52944

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:

Central Coast Water Board Central Coast Water Board Staff assessed public submissions data for Bennett Slough to determine beneficial use support and results are as follows: 20 of 28 samples exceed the criterion for pH.

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 72146, pH	Region 3
Bennett Slough

LOE ID:

15157

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Non-Contact Recreation

Number of Samples:

856

Number of Exceedances:

402

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/20/1990-10/10/2006.

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 72146, pH	Region 3
Bennett Slough

LOE ID:

15158

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

856

Number of Exceedances:

297

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/20/1990-10/10/2006.

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 72146, pH	Region 3
Bennett Slough

LOE ID:

52952

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:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 72146, pH	Region 3
Bennett Slough

LOE ID:

15156

Pollutant:

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

856

Number of Exceedances:

402

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.

Objective/Criterion Reference:

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

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/20/1990-10/10/2006.

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 72146, pH	Region 3
Bennett Slough

LOE ID:

52937

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:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3


DECISION ID	80355	Region 3
Bennett Slough

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)(2016)
Revision Status	Original
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Three of the 48 nitrate samples exceed the water quality objective and 6 of the 81 nitrate/nitrite samples exceed the evaluation guideline used to interpret the narrative water quality objective for bio-stimulatory substances. 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. Three of the 48 nitrate samples exceed the water quality objective and 6 of the 81 nitrate/nitrite samples exceed the evaluation guideline used to interpret the narrative water quality objective for bio-stimulatory substances 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 80355, Nitrate	Region 3
Bennett Slough

LOE ID:

52842

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:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

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:

Staff Report Division of Water Quality Nutrient Screening Tools for Use in the Clean Water Act Section 303(d) Listing Process

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 Bennett Slough was collected at 4 monitoring sites [ 305BENSTP - Bennett Slough at Struve Pond , 306BENEH1 - Bennett Slough East of Highway 1 , 306BENWH1 - Bennett Slough West of Highway 1 , 306BENJTR - Bennett Slough at Jetty Road ]

Temporal Representation:

Data was collected over the time period 1/8/2007-7/7/2009.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 80355, Nitrate	Region 3
Bennett Slough

LOE ID:

52867

Pollutant:

Nitrate/Nitrite (Nitrite + Nitrate as N)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Central Coast Water Board Staff assessed public submissions data for Bennett Slough to determine beneficial use support and results are as follows: 6 of 81 samples exceed the criterion for Nitrate/Nitrite as N.

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Staff Report Division of Water Quality Nutrient Screening Tools for Use in the Clean Water Act Section 303(d) Listing Process

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:

Temporal Representation:

Data was collected over the time period 3/5/2007-7/7/2009.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 80355, Nitrate	Region 3
Bennett Slough

LOE ID:

52832

Pollutant:

Nitrate

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Staff Report Division of Water Quality Nutrient Screening Tools for Use in the Clean Water Act Section 303(d) Listing Process

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:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/7/2009.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 80355, Nitrate	Region 3
Bennett Slough

LOE ID:

52906

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:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Guideline Reference:

Staff Report Division of Water Quality Nutrient Screening Tools for Use in the Clean Water Act Section 303(d) Listing Process

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:

Temporal Representation:

Data was collected over the time period 3/5/2007-7/7/2009.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3


DECISION ID	80353	Region 3
Bennett Slough

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

Regional Board Conclusion:	This pollutant is being considered for placement on the 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. A total of 114 of the 932 samples exceed the evaluation guideline (Moyle 1976) used to interpret the aquatic life water quality objective. 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. A total of 114 of the 932 samples exceed the evaluation guideline (Moyle 1976) used to interpret the aquatic life water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

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

State Board Review of Regional Board Conclusion and Recommendation:

State Board Decision Recommendation:	After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.

Line of Evidence (LOE) for Decision ID 80353, Temperature, water	Region 3
Bennett Slough

LOE ID:

15242

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

904

Number of Exceedances:

110

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed National Estuarine Research Reserve Monitoring Program (R3_ESNERR) data for Bennett Slough to determine beneficial use support and results are as follows: 110 of 904 samples exceed the criterion for Water Temperature.

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Natural receiving water temperature of intrastate waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses (General Objective in Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).

Objective/Criterion Reference:

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

Evaluation Guideline:

Inland Fishes of California (Moyle 1976) states that for rainbow trout the optimum range for growth and completion of most life stages is 13-21 degrees C (page 129).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/20/1990-10/10/2006.

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 80353, Temperature, water	Region 3
Bennett Slough

LOE ID:

52975

Pollutant:

Temperature, water

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Central Coast Water Board Staff assessed public submissions data for Bennett Slough to determine beneficial use support and results are as follows: 4 of 28 samples exceed the criterion for Water Temperature.

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

The optimum range for growth and completion of most life stages of rainbow trout is 13-21 degrees Celsius (Moyle 1976).

Guideline Reference:

Inland Fishes of California

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3


DECISION ID	80354	Region 3
Bennett Slough

Pollutant:	Turbidity
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2023
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	This pollutant is being considered for placement on the section 303(d) list under sections 2.1 and 3.2 of the Listing Policy. Four lines of evidence are available in the administrative record to assess this pollutant. Two-hundred-eighty-none of 907 samples exceed the Evaluation Guideline (Shoup, D.E. and Wahl D.H., 2009) used to interpret the Warm Freshwater Habitat water quality objective and 292 of 907 samples exceed the evaluation guideline (Sigler et al., 1984) used to interpret the Cold Freshwater Habitat water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two-hundred-eighty-none of 907 samples exceed the Evaluation Guideline (Shoup, D.E. and Wahl D.H., 2009) used to interpret the Warm Freshwater Habitat water quality objective and 292 of 907 samples exceed the evaluation guideline (Sigler et al., 1984) used to interpret the Cold Freshwater Habitat water quality objective 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 80354, Turbidity	Region 3
Bennett Slough

LOE ID:

52960

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Water Board Central Coast Water Board Staff assessed public submissions data for Bennett Slough to determine beneficial use support and results are as follows: 12 of 28 samples exceed the criterion for Turbidity(NTU).

Data Reference:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

Evaluation Guideline:

Turbidities of 25 NTU or greater can cause a reduction in juvenile salmonid growth due to interference with their ability to find food (Sigler et al. 1984).

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:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 80354, Turbidity	Region 3
Bennett Slough

LOE ID:

52967

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:

Data from Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program, Jan. 2007-Jul. 2009

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:

Water Quality Control Plan for the Central Coastal Basin

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:

Temporal Representation:

Data was collected over the time period 1/8/2007-7/10/2007.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):

Quality Assurance Project Plan, Elkhorn Slough National Estuarine Research Reserve Volunteer Monthly Water Quality Program. May 15, 2009, Ver.1.3

Line of Evidence (LOE) for Decision ID 80354, Turbidity	Region 3
Bennett Slough

LOE ID:

15277

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Aquatic Life Use:

Cold Freshwater Habitat

Number of Samples:

879

Number of Exceedances:

280

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed National Estuarine Research Reserve Monitoring Program (R3_ESNERR) data for Bennett Slough to determine beneficial use support and results are as follows: 280 of 879 samples exceed the criterion for Turbidity(NTU).

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.

Objective/Criterion Reference:

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

Evaluation Guideline:

Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.

Guideline Reference:

Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150

Spatial Representation:

Temporal Representation:

Data was collected over the time period 1/20/1990-10/10/2006.

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 80354, Turbidity	Region 3
Bennett Slough

LOE ID:

15292

Pollutant:

Turbidity

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Warm Freshwater Habitat

Aquatic Life Use:

Warm Freshwater Habitat

Number of Samples:

879

Number of Exceedances:

280

Data and Information Type:

PHYSICAL/CHEMICAL MONITORING

Data Used to Assess Water Quality:

Central Coast Regional Board Staff assessed National Estuarine Research Reserve Monitoring Program (R3_ESNERR) data for Bennett Slough to determine beneficial use support and results are as follows: 280 of 879 samples exceed the criterion for Turbidity(NTU).

Data Reference:

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Field Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 2006

Final Data File used for assessment: ESNERR (Elkhorn Slough National Reserve) Water Quality Data from 94-04

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

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:

Data was collected over the time period 1/20/1990-10/10/2006.

Environmental Conditions:

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

QAPP Information:

QAPP Information Reference(s):