Final California 2024 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 1 - North Coast Region

Water Body Name:	Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough
Water Body ID:	CAR1100004020140113044906
Water Body Type:	River & Stream


DECISION ID	75761	Region 1
Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough

Pollutant:	Indicator Bacteria
Final Listing Decision:	List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	A Source Unknown
Expected TMDL Completion Date:	2025
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	The "Eureka Plain HU, Elk River" water body has been split into three water bodies for the current Integrated Report cycle: (1) Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough, (2) Eureka Plain HU, Elk River Watershed, Upper Elk River, and (3) Eureka Plain HU, Elk River Watershed, Upper Little South Fork Elk River. LOEs 47453, 47450,47488, and 47489 are new for the current Integrated Report cycle. Fecal indicator bacteria (which includes E. coli and fecal coliform) are being considered for placement on the Section 303(d) list under Section 3.2 and 3.3 of the Listing Policy. Under these sections a single line of evidence (LOE) is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess fecal indicator bacteria in the lower mainstem Elk River and two lines of evidence are available to assess fecal indicator bacteria in Martin Slough. In accordance with Section 3.3 of the Listing Policy, a 4% exceedance rate shall be used to add waters to the List "if water quality monitoring was conducted April 1 through October 31 only". The E. coli data collected in Martin Slough (LOE 47489), the fecal coliform data collected in the lower Elk River (LOE 47450), and the E. coli data collected in the lower Elk River (LOE 47488) were collected during this timeframe only. One of one fecal coliform sample from the lower Elk River violates the evaluation guideline, however this sample size is insufficient to determine with the power and confidence of the listing policy if standards are being met as there must be either (1) at least 22 samples available for evaluation in order to make a listing determination or (2) 3 or more exceedances from less than 22 samples in which case listing can occur. Six of 8 E. coli samples from Martin Slough and 5 of 6 E. coli samples from the lower Elk River exceed the evaluation guideline and this violates the allowed 4% exceedance frequency. The fecal coliform data assessed in LOE 47453 for Martin Slough includes data collected during months outside the April - October range. Therefore, the data are being considered under section 3.2 of the Listing Policy, using a 10% exceedance rate. Four of 6 fecal coliform samples from Martin Slough exceed the evaluation guideline, and this sample size is insufficient to determine with the power and confidence of the listing policy if standards are being met as there must be either (1) at least 26 samples available for evaluation in order to make a listing determination under section 3.2 or (2) 5 or more exceedances from less than 26 samples in which case listing can occur. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing the lower mainstem Elk River and Martin Slough on the Section 303(d) list for Indicator Bacteria (i.e., sufficient justification to list). This conclusion is based on the staff findings that: (1) The data used satisfy the data quality requirements of Section 6.1.4 of the Policy. (2) The data used satisfy the data quantity requirements of Section 6.1.5 of the Policy. (3) 6 of 8 E. coli samples from the Martin Slough and 5 of 6 E. coli samples from the lower mainstem Elk River exceeded the evaluation guideline and this exceeds the allowable 4% exceedance frequency from 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 region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

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 75761, Indicator Bacteria	Region 1
Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough

LOE ID:

47489

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:

Not Specified

Data Used to Assess Water Quality:

Six of the eight samples exceeded the E. coli evaluation guideline.

Data Reference:

Data for bacteria in various North Coast Region water bodies

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2011): The bacteriological quality of waters of the North Coast Region shall not be degraded beyond natural background levels.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Draft Guidance for Fresh Water Beaches (CDPH 2011): Beach posting is recommended when single sample E. coli levels exceed 235 MPN / 100 ml.

Guideline Reference:

Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.

Spatial Representation:

The samples were collected at Martin Slough at Campton and Fern, tributary to Elk River and Martin Slough at Fairway.

Temporal Representation:

The samples were collected September 2008 to October 2009.

Environmental Conditions:

QAPP Information:

The samples were collected under the Redwood Community Action Agency's Humboldt Bay First Flush Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75761, Indicator Bacteria	Region 1
Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough

LOE ID:

47488

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:

Not Specified

Data Used to Assess Water Quality:

Five of the six samples exceeded the E. coli evaluation guideline.

Data Reference:

Data for bacteria in various North Coast Region water bodies

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Water Quality Control Plan, North Coast Region (NCRWQCB 2011): The bacteriological quality of waters of the North Coast Region shall not be degraded beyond natural background levels.

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Draft Guidance for Fresh Water Beaches (CDPH 2011): Beach posting is recommended when single sample E. coli levels exceed 235 MPN / 100 ml.

Guideline Reference:

Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.

Spatial Representation:

The samples were collected at Elk River at Berta, and Elk River at Zanes Road/Estevos.

Temporal Representation:

The sample was collected between September 2008 and October 2009.

Environmental Conditions:

QAPP Information:

The samples were collected under the Redwood Community Action Agency's Humboldt Bay First Flush Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75761, Indicator Bacteria	Region 1
Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough

LOE ID:

47453

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Four of the six samples exceeded the fecal coliform evaluation guideline. Since less than 5 samples over a 30-day period were collected, the evaluation guideline is used for comparison to the samples.

Data Reference:

Data for bacteria in various North Coast Region water bodies

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteriological quality of waters of the North Coast Region shall not be degraded beyond natural background levels. In no case shall coliform concentrations in waters of the North Coast Region exceed the following: In waters designated for contact recreation (REC-1), the median fecal coliform concentration based on a minimum of not less than 5 samples for any 30-day period shall not exceed 50 MPN/ 100 ml, nor shall more than 10% of total samples during any 30-day period exceed 400 MPN / 100 ml. Water Quality Control Plan, North Coast Region (NCRWQCB 2011).

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Beach posting is recommended when single sample fecal coliform levels exceed 400 MPN / 100 ml. Draft Guidance for Fresh Water Beaches (DHS 2011).

Guideline Reference:

Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.

Spatial Representation:

The samples were collected at Martin Slough at Campton and Fern, tributary to Elk River and Martin Slough at Fairway, tributary to Elk River.

Temporal Representation:

The samples were collected between September 2006to May 2008.

Environmental Conditions:

QAPP Information:

The samples were collected under the Redwood Community Action Agency's Humboldt Bay First Flush Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 75761, Indicator Bacteria	Region 1
Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough

LOE ID:

47450

Pollutant:

Fecal Coliform

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

One of the one sample exceededs the fecal coliform evaluation guideline. Since less than 5 samples over a 30-day period were collected, the evaluation guideline is used for comparison to the samples.

Data Reference:

Data for bacteria in various North Coast Region water bodies

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Water Quality Control Plan (Basin Plan) for the North Coast Region

Evaluation Guideline:

Beach posting is recommended when single sample fecal coliform levels exceed 400 MPN / 100 ml. Draft Guidance for Fresh Water Beaches (DHS 2011).

Guideline Reference:

Draft Guidance for Fresh Water Beaches. Last Update: May 8, 2006. Initial Draft: November 1997. California Department of Public Health.

Spatial Representation:

The samples were collected at Elk River at Berta, and Elk River at Zanes Road/Estevos. This water body will be changed to Lower Elk River and Martin Slough in the next Integrated Report cycle.

Temporal Representation:

The sample was collected on October 10, 2007.

Environmental Conditions:

QAPP Information:

The samples were collected under the Redwood Community Action Agency's Humboldt Bay First Flush Quality Assurance Project Plan.

QAPP Information Reference(s):


DECISION ID	74266	Region 1
Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough

Pollutant:	Sediment
Final Listing Decision:	List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision:	List on 303(d) list (TMDL required list)(2016)
Revision Status	Original
Sources:	Logging Road Construction/Maintenance \| Road Construction \| Silviculture
TMDL Name:	Upper Elk River and Upper Little South Fork Elk River Sediment TMDL
TMDL Project Code:	93
Date TMDL Approved by USEPA:	04/04/2018
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: The pollutant name has been changed from "sedimentation/siltation" to "sediment". The pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle, however there is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard. The previous conclusion remains unchanged, and is as follows: The "Eureka Plain HU, Elk River" water body has been split into three water bodies for the current Integrated Report cycle: (1) Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough, (2) Eureka Plain HU, Elk River Watershed, Upper Elk River, and (3) Eureka Plain HU, Elk River Watershed, Upper Little South Fork Elk River. LOE 47457 is a copy of placeholder LOE 3667 from the 2006 Listing cycle. There are no new data for this water segment-pollutant combination for the current Integrated Report cycle. Regional Water Board conclusion: This pollutant was considered for placement on the section 303(d) List in a previous Integrated Report cycle. No new information was reviewed for this current Integrated Report cycle. Therefore, the previous conclusion remains unchanged, and is as follows: 303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed.

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 74266, Sediment	Region 1
Eureka Plain HU, Elk River Watershed, Lower Elk River and Martin Slough

LOE ID:

47457

Pollutant:

Sedimentation/Siltation

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Cold Freshwater Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference pre-2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Unknown

Temporal Representation:

Unknown

Environmental Conditions:

Unknown

QAPP Information:

Unknown

QAPP Information Reference(s):