Draft 2008 California 303(d)/305(b) Integrated Report

Supporting Information

Regional Board 4 - Los Angeles Region

Water Body Name: Canada Larga (Ventura River Watershed)
Water Body ID: CAR4021001020020131161119
Water Body Type: River & Stream
 
DECISION ID
13212
 
Pollutant: Total Dissolved Solids
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Weight of Evidence: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant.

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. 21 of 51 samples exceed the Basin Plan Water Quality Objective for Selected Constituents in Inland Surface Waters (water body specific for Ventura River Reach 2) of 1500 mg/L for TDS, 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 met.
 
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.
 
SWRCB Board Decision / Staff Recommendation:
 
USEPA Decision:
 
 
Lines of Evidence (LOEs) for Decision ID 13212
 
LOE ID: 25720
 
Pollutant: Total Dissolved Solids
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Municipal & Domestic Supply
 
Number of Samples: 51
Number of Exceedances: 21
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Data collected for the Santa Barbara ChannelKeeper Water Quality Monitoring Program (2001 to 2007). A total of 21 out of 51 samples exceeded the water quality objective of 1500 mg/L.
Data Reference: Santa Barbara Channelkeeper Water Quality Data Submittal and 303(d) List Recommendations
 
Water Quality Objective/Criterion: Los Angeles RWQCB Basin Plan Water Quality Objective for Selected Constituents in Inland Surface Waters--water body specific for Ventura River Reach 2--is 1500 mg/L for TDS. By the tributary rule this objective also applies to Canada Larga.
Objective/Criterion Reference: Water Quality Control Plan Los Angeles Region R4 Basin Plan
  Basin Plan Amendments to the Water Quality Control Plan Los Angeles Region R4 Basin Plan as of 02/02/2009
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: VR04 sampling site is located downstream of the Canada Larga bridge (Lat 34.336916, Long -119.294114). VR05 sampling site is located 3.5 miles up Canada Laraga Road, at a small bridge over the creek (Lat 34.357559, Long -119.252581).
Temporal Representation: Grab samples taken and analyzed on monthly basis from August 2001 to May 2006.
Environmental Conditions:
QAPP Information: Data collected and analyzed according to the provisions of the Ventura River Watershed Monitoring Program Quality Assurance Project Plan (Santa Barbara Channelkeeper, October 2004).
QAPP Information Reference(s): Ventura River Watershed Monitoring Program Quality Assurance Project Plan (Santa Barbara Channelkeeper, October 2004)