Final California 2012 Integrated Report( 303(d) List/305(b) Report)

Supporting Information

Regional Board 4 - Los Angeles Region

Water Body Name: Medea Creek Reach 2 (Abv Confl. with Lindero)
Water Body ID: CAR4042300019990201140017
Water Body Type: River & Stream
 
DECISION ID
30331
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
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)(2010)
Revision Status Original
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

Regional Board Conclusion:
This pollutant is being considered for the section 303(d) list under section 3.9 of the Listing Policy. Under section 3.9, waters are listed when a bioassessment shows diminished numbers of species or other metrics (compared to a reference site) and it is associated with another pollutant.

One line of evidence is available in the administrative record to assess this pollutant. Benthic macroinvertebrates as measured by Southern California IBI (Index of Biological Integrity) in Medea Creek Reach 2 were very poor in the spring and very poor in the fall of 2005 indicating impairment of benthic community structure.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification to place the water segment in category 4C on the section 303(d) list in the Water Quality Limited Segments.

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. There is at least one bioassessment sample (Index of Biological Integrity score) to satisfy Section 3.9
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.



State Board Review and Conclusion:
State Water Board staff used a situation-specific weight of evidence approach to evaluate the Los Angeles Water Board benthic macroinvertebrate –bioassessment listing. State Water Board staff determined that it is necessary to include these listings because additional data analyses and multiple line of evidence show that benthic macroinvertebrate populations are impacted by a wide range of stressors. Using this approach staff followed a three-step process for evaluation of all available water quality data including the chemistry and bioassessment data. In the first step, staff reviewed the Los Angeles Water Board data evaluation for bioassessment listing. In the second step, staff reviewed all other available bioassessment data because State Water Board staff learned that some data had not been considered for this listing decision by the Regional Water Board. In step 3 staff reviewed the chemistry water quality data available for total nitrogen and total phosphorus to determine the water quality condition in this water body segment.

In step 1 and 2, State Water Board staff evaluated the bioassessment data using the Southern California index of biological integrity (IBI). Staff reviewed the line of evidence prepared by the Los Angeles Water Board and additional bioassessment data. Benthic macroinvertebrate as measured by Southern California IBI in Medea Creek Reach 2 (Abv Confl. with Lindero) were poor in years 2000 through 2006 indicating impairment of benthic community structure.

In step 3, the water quality data for total nitrogen and total phosphorus were evaluated by State Water Board staff. Data for selenium, invasive species trash, coliform bacteria, sedimentation/siltation, and algae.were evaluated in a previous listing cycle. Selenium, invasive species trash, coliform bacteria, sedimentation/siltation, and algae showed impairment to the warm freshwater habitat, non-contact recreation, and water contact recreation and it resulted in listing this water body in 1996 and 2002. In this step State Water Board staff evaluated the most recent available data for total nitrogen and total phosphorus. The data for total nitrogen show that samples exceeded the water quality objective. The data for total nitrogen show that samples exceeded the water quality objective. The weight of evidence of the data and information indicate that the beneficial use of the water is not supported.

The water quality chemistry and bioassessment data provide a substantial basis that benthic macroinvertebrate populations are impacted by a wide range of anthropogenic stressors. Based on the available data and information, staff recommend to list for benthic macroinvertebrate-bioassessment.
 
Regional Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be added to the section 303(d) list because applicable water quality standards are not being attained.
 
State Board Staff Review of Regional Board Conclusion and Recommendation: The water quality chemistry and bioassessment data provide a substantial basis that benthic macroinvertebrate populations are impacted by a wide range of anthropogenic stressors. Based on the available data and information, staff recommend to list for benthic macroinvertebrate-bioassessment.
 
State Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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 30331, Benthic-Macroinvertebrate Bioassessments
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
LOE ID: 30181
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat | Preservation of Rare & Endangered Species | Wetland Habitat | Wildlife Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: The IBI scores at these sites ranked in the “very poor” range (13 and 10) in the spring and “very poor” (11 and 10) in the fall.
Data Reference: Malibu Watershed 2005 Bioassessment Monitoring Report. (2005) The Malibu Creek Watershed Monitoring Program City of Calabasas, Environmental Services Division. Submitted by: Aquatic Bioassay and Consulting Laboratories.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Basin Plan states that: "All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration or other appropriate methods as specified by the State or Regional Board.”
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 Basin Plan 1997-2009
 
Evaluation Guideline: The IBI is a multi-metric assessment that employs biological metrics that respond to a habitat or water quality impairment. Each of the biological metrics measured at a site are converted to an IBI score then summed. These cumulative scores are then ranked as very good (80-100), good (60-79), fair (40-49), poor (20-39) and very poor (0-19) habitat conditions. Sites with scores below 39 are considered to have impaired conditions.
Guideline Reference: A Quantitative Tool for Assessing the Integrity of Southern Coastal California Streams. Appendix 7-B Environmental Management Vol. 35, No. 4, pp. 493-504.
 
Spatial Representation: Two sites in Medea Creek were sampled, MED1 above the confluence with Lindero Creek at 34° 10.180' N 118° 45.762' W and MED2 near the confluence with Malibu Creek at 34° 06.865' N 118° 45.328' W.
Temporal Representation: Sites were sampled in Spring and Fall of 2005
Environmental Conditions: Benthic macroinvertebrate populations and IBI scores may also be affected by a wide range of anthropogenic stressors.
QAPP Information: Data was collected in compliance with California Stream Bioassessment Procedure.
QAPP Information Reference(s): California Stream Bioassessment Procedure (Protocol Brief for Biological and Physical/Habitat Assessment in Wadeable Streams) California Department of Fish and Game Water Pollution Control Laboratory Aquatic Bioassessment Laboratory Revision Date - December, 2003
 
 
DECISION ID
28858
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
Pollutant: Invasive Species
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)(2010)
Revision Status Original
Sources: Source Unknown
Expected TMDL Completion Date: 2021
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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, waters are listed when a declining trend in water quality is substantiated.

Two lines of evidence are available in the administrative record to assess this pollutant. One of 4 sites showed an increase in density of mud snails over the three years of sampling (2006, 2007, 2008) and 4 out of 4 sites sampled showed medium or high densities of mud snail in 2008.

At high numbers, mud snails can completely cover a stream bed and damage local stream ecosystems. The colonies outcompete native aquatic invertebrates that the watershed’s fish and amphibians rely on for food, disrupting the entire food web.

Benthic macroinvertebrates as measured by Southern California IBI (index of biological integrity) in Medea Creek were very poor in 2005 indicating impairment of benthic community structure.

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. Data was collected over a three years time frame and a baseline condition of zero abundance of the invasive species was used.
3. One of three sites showed an increase in density of mud snails over a three years of sampling and three of three sites sampled showed medium or high densities of mud snail in 2008.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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 Staff Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
 
Line of Evidence (LOE) for Decision ID 28858, Invasive Species
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
LOE ID: 28713
 
Pollutant: Invasive Species
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat | Preservation of Rare & Endangered Species | Wetland Habitat | Wildlife Habitat
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: A total of one of three sites showed an increase in density of mud snails over the three years of sampling (2006, 2007, 2008) and three of three sites sampled showed medium or high densities of mud snail in 2008.
Data Reference: New Zealand Mudsnail Surveys July 2006, July 2007 and October 2008 Santa Monica Mountains. Santa Monica Bay Restoration Commission / Santa Monica Baykeeper.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Basin Plan states that: "All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration or other appropriate methods as specified by the State or Regional Board.”
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 Basin Plan 1997-2009
 
Evaluation Guideline: Presence of high densities and increasing densities. While quantitative and predictive research continues, due to its ability to attain extremely high densities, the impacts of the mudsnails on aquatic ecosystems where it occurs in the western U.S. are large and include: decreased densities of native macroinvertebrates and reduced food resources; decreased whole-stream algal production; poor food source in that mudsnails are much more difficult to digest, with their hard shells and operculum than are the thin-shelled, native pulmonate snails that do not have opercula or than soft-bodied, aquatic insect larvae.
Guideline Reference: The New Zealand Mudsnail Invades the Western United States. Aquatic Nuisance Species Digest Volume 4 No. 4.
 
Spatial Representation: Four sites were sampled in the following locations in Medea Creek Reach 2: Conifer St. under bridge on left side; Chumash Park; Cornell at Kanan Rd; and the outlet at Paramount Ranch.
Temporal Representation: All sites were sampled in July of 2006, July of 2007 and October of 2008.
Environmental Conditions:
QAPP Information: Data was collected as detailed in the Santa Monica Bay Restoration Commission and Santa Monica Baykeeper New Zealand Mudsnail Surveys.
QAPP Information Reference(s): New Zealand Mudsnail Surveys July 2006, July 2007 and October 2008 Santa Monica Mountains. Santa Monica Bay Restoration Commission / Santa Monica Baykeeper.
 
Line of Evidence (LOE) for Decision ID 28858, Invasive Species
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
LOE ID: 30181
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Cold Freshwater Habitat | Preservation of Rare & Endangered Species | Wetland Habitat | Wildlife Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: The IBI scores at these sites ranked in the “very poor” range (13 and 10) in the spring and “very poor” (11 and 10) in the fall.
Data Reference: Malibu Watershed 2005 Bioassessment Monitoring Report. (2005) The Malibu Creek Watershed Monitoring Program City of Calabasas, Environmental Services Division. Submitted by: Aquatic Bioassay and Consulting Laboratories.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Basin Plan states that: "All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrimental physiological responses in, human, plant or animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analysis of species diversity, population density, growth anomalies, bioassays of appropriate duration or other appropriate methods as specified by the State or Regional Board.”
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 Basin Plan 1997-2009
 
Evaluation Guideline: The IBI is a multi-metric assessment that employs biological metrics that respond to a habitat or water quality impairment. Each of the biological metrics measured at a site are converted to an IBI score then summed. These cumulative scores are then ranked as very good (80-100), good (60-79), fair (40-49), poor (20-39) and very poor (0-19) habitat conditions. Sites with scores below 39 are considered to have impaired conditions.
Guideline Reference: A Quantitative Tool for Assessing the Integrity of Southern Coastal California Streams. Appendix 7-B Environmental Management Vol. 35, No. 4, pp. 493-504.
 
Spatial Representation: Two sites in Medea Creek were sampled, MED1 above the confluence with Lindero Creek at 34° 10.180' N 118° 45.762' W and MED2 near the confluence with Malibu Creek at 34° 06.865' N 118° 45.328' W.
Temporal Representation: Sites were sampled in Spring and Fall of 2005
Environmental Conditions: Benthic macroinvertebrate populations and IBI scores may also be affected by a wide range of anthropogenic stressors.
QAPP Information: Data was collected in compliance with California Stream Bioassessment Procedure.
QAPP Information Reference(s): California Stream Bioassessment Procedure (Protocol Brief for Biological and Physical/Habitat Assessment in Wadeable Streams) California Department of Fish and Game Water Pollution Control Laboratory Aquatic Bioassessment Laboratory Revision Date - December, 2003
 
 
DECISION ID
20649
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
Pollutant: Sedimentation/Siltation
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)(2010)
Revision Status Original
Sources: Source Unknown
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
State Board Staff Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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 20649, Sedimentation/Siltation
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
LOE ID: 4347
 
Pollutant: Sedimentation/Siltation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--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: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
 
DECISION ID
30407
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
Pollutant: Selenium
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)(2010)
Revision Status Original
Sources: Source Unknown
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
State Board Staff Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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 30407, Selenium
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
LOE ID: 4348
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--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: Unspecified
Objective/Criterion Reference: Placeholder reference pre-2006 303(d)
 
Evaluation Guideline: Unspecified
Guideline Reference: Placeholder reference pre-2006 303(d)
 
Spatial Representation: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
 
DECISION ID
20651
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
Pollutant: Trash
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)(2010)
Revision Status Original
Sources: Source Unknown
Expected TMDL Completion Date: 2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
State Board Staff Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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 20651, Trash
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
LOE ID: 4349
 
Pollutant: Trash
LOE Subgroup: Visual
Matrix: -N/A
Fraction: Not Recorded
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--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: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
 
DECISION ID
28847
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
Pollutant: Algae
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 (being addressed by USEPA approved TMDL)(2010)
Revision Status Original
Sources: Agriculture-animal | Atmospheric Deposition | Golf course activities | Groundwater Loadings | Irrigated Crop Production | Major Municipal Point Source-dry and/or wet weather discharge | Onsite Wastewater Systems (Septic Tanks) | Urban Runoff/Storm Sewers
TMDL Name: Malibu Creek Nutrients
TMDL Project Code: 239
Date TMDL Approved by USEPA: 03/21/2003
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

This pollutant is being considered for removal on the section 303(d) list under sections 2.2 of the Listing Policy. Under 2.2 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Two lines of evidence are 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 against removing this water segment-pollutant combination from the section 303(d) list. There is sufficient justification to place it in the Being Addressed portion of the 303(d) list because a TMDL has been established by USEPA, and is expected to result in attainment of the standard.
 
Regional Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the Water Quality Limited Segments Being Addressed category of the section 303(d) list because a TMDL has been established by USEPA, and applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Staff Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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 28847, Algae
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
LOE ID: 28630
 
Pollutant: Algae
LOE Subgroup: Narrative Description Data
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: A TMDL has been established for this water segment-pollutant combination. The Malibu Creek Watershed Nutrient TMDL was established by USEPA on March 21, 2003.
Data Reference: Staff report, appendix, and letter to SWRCB and Los Angeles RWQCB establishing a TMDL for Nutrients in the Malibu Creek Watershed.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA information unavailable.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 28847, Algae
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
LOE ID: 4346
 
Pollutant: Algae
LOE Subgroup: Pollutant-Nuisance
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Unspecified--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: Unspecified
Temporal Representation: Unspecified
Environmental Conditions: Unspecified
QAPP Information: Unspecified
QAPP Information Reference(s):
 
 
DECISION ID
20546
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
Pollutant: Coliform Bacteria
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 (being addressed by USEPA approved TMDL)(2010)
Revision Status Original
Sources: Nonpoint Source
TMDL Name: Malibu Pathogens
TMDL Project Code: 236
Date TMDL Approved by USEPA: 01/10/2006
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

This pollutant is being considered for listing under section 2.2 of the Listing Policy. Under this section of the Policy, a minimum of one line of evidence is needed to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. A TMDL has been developed and approved by USEPA and an approved implementation plan is expected to result in attainment of the standard. The Malibu Creek Watershed Bacteria TMDL was approved by USEPA in January of 2006.

Based on the readily available information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination in the Water Quality Limited Segments Being Addressed portion of the section 303(d) list.
 
Regional Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
State Board Staff Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: Region 4 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.

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 20546, Coliform Bacteria
Region 4     
Medea Creek Reach 2 (Abv Confl. with Lindero)
 
LOE ID: 2262
 
Pollutant: Coliform Bacteria
LOE Subgroup: Pollutant-Water
Matrix: Not Specified
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: NJK: This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion:
Objective/Criterion Reference:
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation:
Temporal Representation:
Environmental Conditions:
QAPP Information: QA Info Missing
QAPP Information Reference(s):