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DECISION ID |
16327 |
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| Pollutant: |
Indicator Bacteria |
| Final Listing Decision: |
List on 303(d) list (TMDL required list) |
| Last Listing Cycle's Final Listing Decision: |
New Decision |
| Revision Status |
Revised |
| Sources: |
Nonpoint Source | Point Source |
| Expected TMDL Completion Date: |
2021 |
| Impairment from Pollutant or Pollution: |
Pollutant |
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| Weight of Evidence: |
This pollutant is being considered for removal from the section 303(d) list under section 3.3 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.
One line of evidence is available in the administrative record to assess this pollutant.
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 Segment.
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. 19 of 211 samples, sampled year-round, from monitoring station VC14000 exceeded the updated Basin Plan single sample water quality objectives, nine of 48 samples exceeded the geometric mean water quality objectives for indicator bacteria, and this exceeds the allowable frequency listed in Table 3.2 of the Listing Policy for geometric means.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are met. |
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| RWQCB Board Decision / Staff 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. |
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| SWRCB Board Decision / Staff Recommendation: |
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| USEPA Decision: |
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| LOE ID: |
28188 |
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| Pollutant: |
Indicator Bacteria |
| LOE Subgroup: |
Pollutant-Water |
| Matrix: |
Water |
| Fraction: |
None |
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| Beneficial Use: |
Water Contact Recreation |
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| Number of Samples: |
211 |
| Number of Exceedances: |
19 |
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| Data and Information Type: |
Other Agencies/Organizations provided monitoring data |
| Data Used to Assess Water Quality: |
19 out of 211 samples exceeded the Basin Plan single sample water quality objectives for indicator bacteria in marine water and nine out of 48 samples exceeded the Basin Plan geometric mean water quality objectives. Water quality samples were taken and analyzed for indicator bacteria consistent with California Code of Regulations Title 17, sections 7958-7961 and related guidance issued by California Department of Public Health . |
| Data Reference: |
County of Ventura coastal beach bacteria monitoring data for AB411. |
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| Water Quality Objective/Criterion: |
The Basin Plan bacteria objectives state that to protect water contact recreation in marine waters individual samples shall not exceed the following limits: the total coliform density shall not exceed 10000/100 ml; the fecal coliform density shall not exceed 400/100 ml; the enterococcus density shall not exceed 104/100 ml; and the total coliform density shall not exceed 1,000/100 ml, if the ratio of fecal-to-total coliform exceeds 0.1 as single samples. The bacteria objectives also establish that the geometric means of individual samples shall not exceed the following limits: the total coliform density shall not exceed 1000/100 ml, the fecal coliform density shall not exceed 200/100 ml, and the enterococcus density shall not exceed 35/100 ml, as a geometric mean. The bacteria objectives are found in Attachment A of Regional Board Resolution No. 2001-018. |
| Objective/Criterion Reference: |
Water Quality Control Plan Los Angeles Region R4 Basin Plan |
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Basin Plan Amendments to the Water Quality Control Plan Los Angeles Region R4 Basin Plan as of 02/02/2009 |
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| Evaluation Guideline: |
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| Guideline Reference: |
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| Spatial Representation: |
The Ventura County Environmental Health Division conducted sampling at Surfers Knoll at beach monitoring station VC25000, located a 1/4 mile upcoast from Santa Clara River next to the parking lot (Lat: 34.2397, Long: -119.26683). |
| Temporal Representation: |
Grab samples were taken and analyzed on a weekly basis from January 2003 to February 2007. |
| Environmental Conditions: |
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| QAPP Information: |
Data was collected in compliance with the sampling and testing procedures detailed in the California Department of Public Health related guidance. |
| QAPP Information Reference(s): |
Draft Guidance for Salt Water Beaches. Last Update: April 10, 2006. Initial Draft: November 1997. Division of Drinking Water and Environmental Management, California Department of Health Services |
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California Code of Regulations Title 17, sections 7958-7960. |