Prepared in cooperation with the San Luis and Delta Mendota Water Authority Dissolved Pesticide Concentrations Entering the Sacramento–San Joaquin Delta from the Sacramento and San Joaquin Rivers, California, 2012–13 Data Series 876 U.S. Department of the Interior U.S. Geological Survey Cover. View of bridge over the Sacramento River at Freeport, Sacramento, Calif. Photo taken by the author. Dissolved Pesticide Concentrations Entering the Sacramento–San Joaquin Delta from the Sacramento and San Joaquin Rivers, California, 2012–13 By James L. Orlando, Megan McWayne, Corey Sanders, and Michelle Hladik In cooperation with the San Luis and Delta Mendota Water Authority Data Series 876 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2014 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: Orlando, J.L., McWayne, Megan, Sanders, Corey, and Hladik, Michelle, 2014, Dissolved pesticide concentrations entering the Sacramento–San Joaquin Delta from the Sacramento and San Joaquin Rivers, California, 2012–13: U.S. Geological Survey Data Series 876, 28 p., http://dx.doi.org/10.3133/ds876. ISSN 2327-638X (online) iii Contents Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................1 Purpose and Scope ..............................................................................................................................2 Regional Setting ....................................................................................................................................2 Sacramento River Watershed ...................................................................................................2 San Joaquin River Watershed ...................................................................................................2 Pesticide Use .........................................................................................................................................2 Rainfall and Hydrologic Conditions ....................................................................................................4 Procedures and Methods .............................................................................................................................5 Sample Collection .................................................................................................................................5 Sample Processing ...............................................................................................................................5 Analytical Methods for Pesticides .....................................................................................................5 Gas Chromatography/Mass Spectrometry Analysis .............................................................5 Liquid Chromatography With Tandem Mass Spectrometry Analysis .................................8 Method Detection Limits ............................................................................................................8 Quality-Assurance and Quality-Control Methods and Results ..............................................................8 Results ...........................................................................................................................................................11 Sacramento River ...............................................................................................................................22 San Joaquin River ...............................................................................................................................25 Summary........................................................................................................................................................27 References Cited..........................................................................................................................................27 iv Figures 1. Map showing locations of sampling sites in the Sacramento–San Joaquin Delta ...........3 2. Graph showing daily mean streamflow from U.S. Geological Survey streamgages at Sacramento River at Freeport (11447650), and San Joaquin River near Vernalis (11303500) ....................................................................................................4 3. Graph showing pesticide detection frequencies at the Sacramento River at Freeport, May 2012 through July 2013 .....................................................................................23 4. Graph showing numbers of pesticides detected in Sacramento River samples and San Joaquin River samples, and average daily rainfall in the Central Valley ........................................................................................................................23 5. Graph showing concentrations of rice pesticides detected in Sacramento River samples, May 2012 through July 2013 .....................................................................................24 6. Graph showing concentrations of the most frequently detected pesticides in Sacramento River samples, May 2012 through July 2013 ....................................................24 7. Graph showing concentrations of selected pesticides in Sacramento River storm samples collected April 1, 2013, through April 5, 2013, and average daily rainfall in the Sacramento Valley .............................................................................................25 8. Graph showing pesticide detection frequencies at the San Joaquin River near Vernalis, May 2012 through April 2013 ....................................................................................26 9. Graph showing concentrations of the most frequently detected pesticides in San Joaquin River samples, May 2012 through April 2013 ..................................................26 v Tables 1. Surface-water sampling sites located on the Sacramento and San Joaquin Rivers .......4 2. Method detection limits for pesticides in water measured by the U.S. Geological Survey Organic Chemistry Research Laboratory ....................................................................6 3. Pesticide concentrations measured by gas chromatograph with mass spectrometry in environmental and field replicate water samples from the Sacramento and San Joaquin Rivers, and the relative standard deviations between results ............................................................................................................................9 4. Pesticide concentrations measured by liquid chromatography with tandem mass spectrometry in environmental and field replicate water samples from the Sacramento and San Joaquin Rivers, and the relative standard deviations between results ..........................................................................................................................11 5. Minimum, maximum, and median recovery, and standard deviation of the recoveries, represented as a percentage for all compounds added to laboratory spiked water samples .............................................................................................12 6. Pesticide detection frequencies and maximum concentrations measured in environmental water samples collected from the Sacramento and San Joaquin Rivers ............................................................................................................................................14 7. Pesticide concentrations measured in environmental water samples collected from the Sacramento River, May 2012 through July 2013 ....................................................15 8. Pesticide concentrations measured in environmental water samples collected from the San Joaquin River, May 2012 through April 2013 ..................................................18 9. Water-quality parameter data measured in water samples collected from the Sacramento and San Joaquin Rivers, May 2012 through July 2013 ..................................21 vi Conversion Factors SI to Inch/Pound Multiply By To obtain Length millimeter (mm) 0.03937 inch (in.) meter (m) 3.281 foot (ft) kilometer (km) 0.6214 mile (mi) meter (m) 1.094 yard (yd) Area millimeter (mm) 0.03937 inch (in.) Volume liter (L) 1.057 quart (qt) Mass gram (g) 0.03527 ounce, avoirdupois (oz) milligram (mg) 0.00003527 ounce, avoirdupois (oz) Inch/Pound to SI Multiply By To obtain Length inch (in.) 25.4 millimeter (mm) foot (ft) 0.3048 meter (m) mile (mi) 1.609 kilometer (km) Area square mile (mi2) 2.590 square kilometer