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

Supporting Information

Regional Board 5 - Central Valley Region

Water Body Name: Chowchilla River (below Eastman Lake)
Water Body ID: CAR5357000020020610134523
Water Body Type: River & Stream
 
DECISION ID
70108
Region 5     
Chowchilla River (below Eastman Lake)
 
Pollutant: Invasive Species
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: Pollution
 
Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.10 of the Listing Policy. Under section 3.10 one line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Three studies, two in 1969-1971 and one in 1986 were used for this assessment, which showed an overall increase of native and non-native species over time.

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) Three studies were conducted, two in 1969-1971 and one in 1986.
2) Baseline data was taken from the 1969-1971 studies. All three studies sampled the same geographic area, with similar sampling sizes.
3) Rank abundance, Pearson product moment correlations, and principal components analysis were the statistical analyses employed during these studies.
4) The comparison showed a net increase of native and non-native species observed at all sampling sites. The data was based on the percentage of sites the species were collected at for each study.
5) Some native species were collected at more sites in 1986 than in 1969-71. Some non-native species were collected at more sites than in 1969-71. Eight native species increased in the watersheds they were observed from 1969-71 to 1986, while 5 native species decreased. Nine non-native species increased over time from 1969-71 to 1986, while 7 non-native species decreased.
6) It cannot be determined if the trend in water quality is expected to meet water standards by the next listing cycle.
7) 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 70108, Invasive Species
Region 5     
Chowchilla River (below Eastman Lake)
 
LOE ID: 2757
 
Pollutant: Invasive Species
LOE Subgroup: Population/Community Degradation
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Fish surveys
Data Used to Assess Water Quality: California roach are almost completely gone from the upper San Joaquin, Fresno, and Chowchilla river systems in central California, apparently from predation from green sunfish. Green sunfish invade small intermittent streams favored by both species, where they can eliminate the roach when the two become trapped together in isolated ponds during summer (Moyle, P.B. 1976).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. Compliance with this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, and biotoxicity tests of appropriate duration or other methods as specified by the Regional Water Board (Central Valley Regional Board Basin Plan, Page III-8.00, Water Quality Objectives.)
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions: Changes in relative diversity and abundance of native species may also be driven by habitat alteration, flow changes, or hydromodification.
QAPP Information: Peer Reviewed Journal Article and Reports.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 70108, Invasive Species
Region 5     
Chowchilla River (below Eastman Lake)
 
LOE ID: 2758
 
Pollutant: Invasive Species
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Fish surveys
Data Used to Assess Water Quality: Two previous studies (conducted in 1969-71) (Moyle and Nichols, 1973; Moyle and Nichols, 1974) were used as baseline comparisons to a study conducted in 1986 (Brown and Moyle, 1993). Data as species percentage was collected and were the same for each baseline study at the sampling sites. The baseline studies and this study each sampled the same geographic area, with each having similar sampling sizes. The baseline data was compared to the data collected in 1986. The comparison showed an overall net increase of native species observed at all sampling sites, as well as a net increase in non-native species. The data was based on the percentage of sites the species were collected at for each study. Overall, some native species were collected at more sites in 1986 (an increase in percent) than in the 1969-71 studies (Brown and Moyle, 1993). Some non-native species were collected at more sites (an increase in percent) than in the 1969-71 studies. Eight native species increased in the watersheds they were observed at (collected at more sites over time) from 1969-71 to 1986, while 5 native species decreased (collected at less sites over time). Nine non-native species increased over time (collected at more sites over time) from 1969-71 to 1986, while 7 non-native species decreased (collected at less sites over time).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life. This objective applies regardless of whether the toxicity is caused by a single substance or the interactive effect of multiple substances. Compliance with this objective will be determined by analyses of indicator organisms, species diversity, population density, growth anomalies, and biotoxicity tests of appropriate duration or other methods as specified by the Regional Water Board (Central Valley Regional Board Basin Plan, Page III-8.00, Water Quality Objectives.)
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Water bodies in the Sierra Nevada were sampled between 90 and 1100 meters elevation and included the Chowchilla River.
Temporal Representation: Baseline studies: 37 samples taken during the summer and autumn of 1969, 1970 and 1971 and 130 samples were taken from 7/27 - 9/4/1970. Another survey was conducted from Sept. 1985 to Sept. 1986 at 186 sites. Only 156 sites were used from this study for statistical analyses, (Brown and Moyle, 1993).
Environmental Conditions: Changes in relative diversity and abundance of native species may also be driven by habitat alteration, flow changes, or hydromodification.
QAPP Information: Peer Reviewed Journal Articles.
QAPP Information Reference(s):