1. Lower San Joaquin Valley Basin -Dormant Spray Organophosphate Monitoring

The United States Geological Survey (USGS) monitored organophosphate pesticides in the lower San Joaquin River Basin during the dormant spray season in January and February 2000. The monitoring plan was developed in cooperation with the Central Valley RWQCB. The weekly sampling will put the storm transport in context with overall transport during the dormant spray application period. Contract period: December 1999 - September 2000.

Final report: Kratzer, C.R., Zamora, C., Knifong, D.L., U.S. Geological Survey. 2002. Diazinon and Chlorpyrifos Loads in the San Joaquin River Basin, California, January and February, 2000. (PDF, 1.4 mb)

2. Lower San Joaquin Valley Dormant Spray Organophosphate Monitoring Continuation

Monitoring by USGS continues for fiscal year 2000. Contract period: January 2001 - December 2001 (winter season).

3. Sacramento/Feather River Diazinon Monitoring

The USGS jointly conducted a monitoring study with DPR to quantify the individual contributions of tributaries to the loading of diazinon to the Sacramento and Feather Rivers during peak flow events in the dormant-spray season. USGS will write the final report for the Feather River watershed diazinon loading study, incorporating data collected by DPR and UCD. Contract period: December 1999 - December 2000.

Final report: Dileanis, P.B., Bennett, K. B., Domalgalski, J.L., U.S.Geological Survey. CDPR. Occurence and Transport of Diazinon in the Sacramento River, California, and Selected Tributaries During Three Winter Storms, January - February, 2000. (PDF, 2 mb)

4. Sacramento/Feather River Diazinon Monitoring Continuation

Monitoring by USGS continues for the fiscal year 2000. Contract period: December 2000 - December 2001 (2000-01 winter runoff season).

5. Chollas Creek Watershed Diazinon/Chlorpyrifos Monitoring

This monitoring study extends the existing monitoring plan that the San Diego Regional Board established. Analysis involves chemical methods for diazinon and chlorpyrifos as well as freshwater bioassays for toxicity on the samples. Collected data will help aid the understanding of organophosphate loading in urban Chollas Creek and the development of the Chollas Creek diazinon TMDL. Contract period May 2000 - June 2002.

Final report: MEC Analytical Systems, Inc. 2002. 1999-2001 Chollas Creek Watershed Monitoring (PDF, 4.5 mb)

6. Upper Sacramento River Watershed Monitoring

The California State University, Chico conducted monitoring for diazinon at seven sites in the Upper Sacramento River watershed. Results will augment diazinon data from the monitoring study in the Sacramento/Feather River watershed. Contract period: January 2001 - June 2001.

7. Controlled Diazinon Runoff Study

California State University, Fresno's Center for Irrigation Technology performed diazinon runoff studies under simulated rainfall/irrigation conditions and differing environmental conditions. Initial studies focused on turf and other bare soil and vegetated surfaces. Variables included slope, rainfall/irrigation intensity, and diazinon formulation. These studies will provide critical information in determining relative contributions of various diazinon formulations in typical residential applications. Contract period April 2000 - June 2001.

EH 02-02 Spurlock, F., C. Garretson, G. Jorgenson, E. Norum, H. Gonsalves, H. Feng, J. Hernandez, and J. Hsu. 2002. Runoff of diazinon from turf: Effect of water application, slope, and formulation. (PDF, 632 kb)

Final Report: Wilen, C., University of California Statewide IPMProject, UC Cooperative Extension, 2001. Survey of Residential Pesticide Use and Sales in the San Diego Creek Watershed of Orange County, California (PDF, 1.9 mb)

9. Diazinon/Chlorpyrifos Runoff Potential Assessment

On behalf of the San Francisco Estuary Project, TDC Environmental conducted an analysis of the relative potential for release of various diazinon and chlorpyrifos products into surface water. The California Department of Pesticide Regulation funded this analysis. The information developed from this project is intended to help DPR, the California State and Regional Water Quality Control Boards, and other interested parties identify potentially problematic sites of use and formulations of diazinon and chlorpyfrifos in the urban setting.

Final report: TDC Environmental, 2001. Diazinon and Chlorpyrifos Products: Screening for Water Quality Implications (PDF, 807 kb)

10. Diazinon Urban Runoff Study

The County of Alameda is evaluating runoff potential of diazinon from paved surfaces. The county will design and construct concrete test plots, equipment will be installed and calibrated to measure flow volume, temperature, wind speed, and other meteorological conditions. Contract period May 2000 - September 2001.

Final report: Feng, A. and J. Scanlin, Prepared for the Alameda County Flood Control and Water Conservation District, 2001.Runoff of diazinon from paved plots and test sites: Summary of results (PDF, 2.6 mb)

11. Residential Irrigation and Rain Runoff Study

The Irvine Ranch Water District will gather data on urban pesticides in irrigation and storm water runoff from three residential neighborhoods. This multi-year study will provide baseline organophosphate residential runoff data during both dry and wet-weather periods. The study will also attempt to measure the effectiveness of runoff management practices on the test neighborhoods. Management practices will be applied by a parallel but independent study which aims to reduce residential runoff and improve runoff quality by using irrigation control devices and by promoting more efficient garden chemical usage. Contract period: December 2000 - June 2003.

12. Urban Land-use Rain Runoff Study

The Southern California Coastal Water Research Project collected and analyzed storm runoff samples associated with various urban land use types. The pesticides of focus are diazinon and chlorpyrifos. Results will help in the allocation of urban pesticide runoff based on land use. Contract period: January 2001 - June 2001.

Final report: Schiff, K. and M. Sutula, 2001. Southern California Coastal Water Research Project, Organophosphorous Pesticides in Stormwater Runoff from Southern California (PDF, 2.7 mb)

13. Irrigation-Season Organophosphate Monitoring in the San Joaquin River Basin

The USGS will assess the extent to which current farming and urban practices, with respect to pesticide usage, contribute to the contamination of surface waters in the Lower San Joaquin River during summer months. The monitoring program includes weekly sampling at 12 major mainstem and tributary sites. Contract period: April 1, 2001 - June 30, 2002.

The Southern California Coastal Water Research Project (SCCWRP) will assess leaching rate from various copper antifouling paints and mass loading from underwater hull cleaning activities under controlled conditions. Contract period: September 1, 2001 - June 30, 2003.

15. Bay Area/Sacramento Urban Pesticide Use Surveys

The University of California, Integrated Pest Management (UC IPM) will conduct surveys of urban pesticide use in the San Francisco Bay Area and Sacramento to help develop a better understanding of urban use patterns. There is no sales survey associated with this study. Contract period: April 1, 2002 - November 1, 2002.

16. California Central Coast Watersheds Study

The Watershed Institute and the Foundation of California State University Monterey Bay (CSUMB) will measure the concentrations of chlorpyrifos and diazinon in the water column and in sediments at 9 sites over a 2-year period. Monitoring will be conducted both during the non-winter irrigation season, and during winter storm events. The monitoring will clarify the linkage between urban and agricultural sources of chlorpyrifos and diazinon and their fate in receiving waters. Contract period: Spring 2002 - Spring 2004.

• Coverletter (PDF 125 kb)
• Interim Report (PDF 903 kb)
• Status Report: Kozlowski D., F. Watson F., J. Larson, J. Wikoff, J. Casagrande, J. Hager, W. Newman, T. Anderson, S. Gilmore. The Watershed Institute. December 2002. Monitoring Chlorpyrifos & Diazinon in Impaired Surface Waters of the Lower Salinas Region (PDF, 1.1 mb)
• Status Report No. 4. Kozlowski D., F. Watson F., Angelo M., J. Larson, J. Wikoff, J. Casagrande, J. Hager, W. Newman, T. Anderson, S. Gilmore. The Watershed Instite. November 2003. Monitoring Chlorpyrifos & Diazinon in Impaired Surface Waters of the Lower Salinas Region (PDF, 1.9 mb)
• Final Report 2004. Kozlowski, D., F. Watson, M. Angelo, and J. Larson. Monitoring Chlorpyrifos and Diazinon in Impaired Surface Waters of the Lower Salinas Region (PDF, 3.5 mb)

17. Aerial Deposition of Selected Pesticides in Southern California

SCCWRP will determine the impact of atmospheric deposition of pesticides transported from sources within the airshed to waterbodies of interest in selected regions of Southern California. The investigation will likely cover portions of RWQCB Regions 4, 7, 8, and 9. Contract period: April 2002 - June 2003.

18. Database Review

Statistical Approaches, UC Davis will develop statistical methodology when applied to the surface water database, will lead to confidence statements for pesticide levels and toxicity and lead to realistic estimates for probabilities of exceeding critical values established by various regulatory agencies.

Final report: Shumway, Robert H., 2001. Statistical Approaches to Assessing Pesticide Concentrations in the DPR Surface Water Database. (PDF 1.9 mb)

19. Diazinon ELISA Evaluation

The University of California, Davis, evaluated interferences in storm water runoff on the diazinon enzyme-linked immunosorbent assay (ELISA). They also evaluated methods to mitigate the presence of potential interferences to improve ELISA selectivity, such as clean-up or extraction procedure modifications. To test these modifications, they analyzed storm water runoff samples using ELISA and compared their results with gas chromatographic analysis performed by the California Department of Food and Agriculture's Center for Analytical Chemistry. Contract period: November 2000 through June 2001.

• Summary Memo (PDF 306 kb)
• Report (PDF 60 kb)

20. Runoff Potential of Multiple Active Ingredients

The California State University's Center for Irrigation Technology is comparing the runoff potential of several pesticide active ingredients. They are responsible for the design and preparation of plots (bare ground), pesticide application, water application, and sample collection. Contract period: August 2001 through June 2002. Project Canceled.

21. Atmospheric Transport of Pesticides in the Sacramento, California Metropolitan Area, 1996-1997

The USGS will finalize its monitoring study on atmospheric transport of pesticides. Air samples were collected in one urban and two agricultural locations in Sacramento County, California. The samples were analyzed for a variety of current use pesticides including dormant orchard spray insecticides, rice herbicides, and urban use pesticides.

Final report: Majewski, M.S. and D.S. Baston, U.S. Geological Survey. 2002. Atmospheric Transport of Pesticides in the Sacramento, California Metropolitan Area, 1996-1997 (PDF, 2.5 mb)

22. Development of Bioassessment Reference Sites in the San Joaquin Valley

In collaboration with the Central Valley Regional Water Quality Control Board, the Department of Fish and Game (DFG), and other government and private agencies, the Department of Pesticide Regulation (DPR) will establish bioassessment reference sites for the San Joaquin Valley. A quantitative method will be established for selecting thirty reference sites within this low-gradient (< 2% slope), anthropogenic-impacted region. Bidwell Environmental Institute (BEI), in association with the California State University, Chico will conduct taxonomy analysis of benthic macroinvertebrates for DPR. Jim Harrington of BEI and DFG will provide technical guidance and a final report to DPR. The final report will include recommendations for the use of bioassessment as a monitoring tool for DPR. Contract period: April 2002 - June 2004.

Harrington, J., California Department of Fish and Game, Water Pollution Control Laboratory and the Chico State Research Foundation. June 2004. Developing a Biological and Physical Habitat Assessment Program for the Department of Pesticide Regulation (PDF, 27 kb)

Contract Manager: Nina Bacey

Evaluate bioavailability of pyrethroids in aqueous/suspended sediment systems, and develop/validate a model that enables prediction of toxicity using LC50 values (determined in water) and basic properties of the aqueous sample, e.g. suspenede solid content and dissolved organic carbon (DOC). Extend model to pore water exposures in bed sediments and validate using biomimetic samplers.

Gan, J. 2004-2006, UC Riverside Workplan (PDF, 25 kb)
Contract Manager: Frank Spurlock

Recent DPR studies on urban pesticide runoff suggest that although residential users likely contribute a large portion of pesticides to urban runoff, other groups of urban users may also be significant contributors. This projects goal was to first comprehensively identify these non-residential urban user groups and then expand our understanding of their pesticide acquisition, use, and disposal practices. The information gathered in this assessment (in combination with those from recent DPR residential user surveys) will then be used to create the most promising comprehensive urban pesticide user outreach strategy. The project's study areas will include the watersheds of Arcade Creek (Sacramento County), San Diego Creek/Upper Newport Bay (Orange County), and Chollas Creek (San Diego County).

25. Mitigation of Urban Use Pesticides in Surface Water Runoff Contract No.: 06-0086C, The Regents of the UC, Davis

Project: This agreement will assist DPR in meeting the needs of protecting surface water from pesticide runoff by providing research in mitigating runoff from insecticide treatment of pests, in evaluating the source, fate, transport, and control of urban use pesticides in urban stream systems.
Term: January 5, 2007 through October 31, 2009

Manager: Kean S. Goh