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Irrigated Lands Regulatory Program - Monitoring Data

Irrigated Lands Regulatory Program - Water Quality Monitoring

Staff Monitoring Data Analysis

UC Davis ILRP Monitoring

  • University of California at Davis (UC Davis) Irrigated Lands Monitoring Project: On 23 November 2002, the Regional Board executed an interagency agreement with the UC Davis to conduct an evaluation of the water quality of the agricultural drains throughout the central valley. The Regional Board staff established a technical advisory committee to assist in developing and implementing the pilot monitoring program addressing discharges from irrigated lands. The advisory committee included members from the Association of Northern California Water Agencies, agricultural groups, environmental groups, Department of Pesticide Regulation, Department of Fish & Game, and UC Davis.

  • UC Davis developed the study plan entitled "Investigation of Water Quality in Agricultural Drains of Central Valley." The objective of this study is: 1 - Evaluate water quality, primarily through use of aquatic species toxicity testing, in a limited number of agricultural drains in the San Joaquin River and Sacramento River watersheds; 2 - Identify the cause of any water quality impairments; 3 - Determine the sources of contaminants based on the identified cause of impairments; and 4 - Recommend water quality investigation designs and approaches for future monitoring and assessment of agricultural runoff and drainage waters based on the lessons learned from this project.
    The Central Valley Regional Water Quality Control Board (CVRWQCB) contracted with the University of California, Davis Aquatic Toxicology Laboratory (UCD ATL) to conduct this investigation. The Study Plan, the final investigation report, and various appendices are available for download with the links provided below:
  • A three-year continuation of the UC Davis project was initiated, and interagency agreements were executed, in December of 2003. This additional investigative work was contracted to the UC Davis John Muir Institute of the Environment and to the California Department of Fish & Game. The additional investigation is known as “Phase II” of the UC Davis project. Phase II was designed to collect additional data to further characterize the quality of water in drains and other channels influenced by agricultural discharges in the Central Valley Region, over a wider geographic area. The Phase II study includes bioassays using three water species and one sediment test species to evaluate toxicity, the analysis of water and sediment for general chemical parameters and many common agricultural chemicals, and further use of toxicity identification evaluation procedures. The project also includes the analysis of drainage samples during both irrigation and storm water runoff events over a two-year period to establish baseline water quality information, and to allow the evaluation of seasonal and temporal changes in water quality. The final report for the Phase II investigation will be completed in December 2006. During the course of the project, UC Davis is providing quarterly status reports, including draft summaries of analytical data. The quarterly reports issued to date are available for download with the links provided below.



If you have any questions, please contact Susan Fregien at (916) 464-4813 or by email at sfregien@waterboards.ca.gov

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--Web page updated 04/25/2011