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

# Supporting Information

## Regional Board 3 - Central Coast Region

Water Body Name: | Waddell Creek, East Branch
Water Body ID: | CAR3041101019980828121908
Water Body Type: | River & Stream

DECISION ID | 4203
Pollutant: | Nutrients
Final Listing Decision: | Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Delist from 303(d) list (TMDL required list)(2006)
Revision Status | Original
Reason for Delisting: | State determines water quality standard is being met
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for removal from the section 303(d) list under section 4.1 of the Listing Policy. Under section 4.1 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. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of removing this water segment-pollutant combination from the section 303(d) list. 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. None of the 54 samples exceeded the unionized ammonia water quality objective and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 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 removed from the section 303(d) list because applicable water quality standards for the pollutant are not being exceeded.
SWRCB Board Decision / Staff Recommendation: | After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should be removed from the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 4203

LOE ID: | 1834
Pollutant: | Nutrients
LOE Subgroup: | Testimonial Evidence
Matrix: | Not Specified
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 54
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Fifty-four samples were collected and the objective was not exceeded in any of the samples (CVRWQCB, 2004B). From Report: The east fork of the Waddell Creek was listed as impaired for nutrients in 1990. The creek was listed because of ammonia violations at the NPDES facility, California Department of Parks and Recreation, Big Basin Redwoods State Park Wastewater Treatment Plant. Another reason for the listing was the California Department of Fish and Game issued a report in 1980 indicating dense growths of filamentous algae were growing downstream of the treatment plant in sunlight areas. They attributed the algal growth to nutrients. Ammonia discharge violations have reoccurred in the past but no violations have occurred since 2002. Ammonia is converted to nitrate through the nitrogen cycle and becomes available as a possible promoter of plant growth. Since the listing in 1990, the treatment plant has been upgraded. The upgrade included the addition of clinoptolite filtration for ammonia removal. Ammonia violations have dramatically decreased since 1998.
Data Reference: | Placeholder reference 2006 303(d)
Water Quality Objective/Criterion: | From delisting report: The Water Quality Control Plan, Central Coast Region (Basin Plan), contains the following unionized ammonia objective: The discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters. The Water Quality Control Plan, Central Coast Region (Basin Plan), contains the following narrative objective: Biostimulatory Substances: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses. This objective does not prohibit biostimulatory substances; it only prohibits biostimulatory substances that cause nuisance or adversely affects beneficial uses.
Objective/Criterion Reference: | Placeholder reference 2006 303(d)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Waddell Creek, East Branch (Calwater Watershed: 30411010), located in Santa Cruz County, California approximately two-thirds of the way from San Francisco to Monterey Bay. Samples were collected at: West Waddell Creek upstream confluence of East Waddell Creek; Opal Creek upstream confluence of East Waddell Creek; Blooms Creek upstream confluence of East Waddell Creek; East Branch of Waddell Creek 145 feet upstream of NPDES discharge; East Branch of Waddell Creek 100 feet downstream of NPDES discharge; East Branch of Waddell Creek approximately 1000 feet upstream of old Last Chance Road bridge crossing; East Branch of Waddell Creek at old Last Chance Road bridge crossing; East Waddell Creek upstream confluence of West Waddell Creek; Lower Waddell Creek ~ one mile downstream confluence of East and West Waddell Creek; Lower Waddell at Alder Camp; Lower Waddell at bridge; Lower Waddell at Marsh Trail.
Temporal Representation: | Started sampling and collecting information on September 24, 2002. We completed the sampling and collection on October 7, 2003.
Environmental Conditions: |
QAPP Information: | All sampling, collection and analysis followed the Regional Board's Central Coast Ambient Monitoring Program's (CCAMP) Quality Assurance Plan.
QAPP Information Reference(s):