Surface Water Models

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Scientists in the Surface Water Protection Program (SWPP), California Department of Pesticide Regulation (CDPR) frequently use simulation models for pesticide risk assessments in product registration evaluation, post-use monitoring, and data analysis. Listed below are selected SWPP models with technical reports and user's manual.


SWMP (Surface Water Monitoring Prioritization Model) Yuzhou Luo, 2015

SWMP model is developed to prioritize pesticides for surface water monitoring in agricultural and urban areas of California. For the generation of monitoring priority lists of pesticide ingredients and their degradates, the model incorporates pesticide use and toxicity data, as well as chemical properties, monitoring results, and application information. Advanced options are also provided in the model for monitoring prioritization at various spatial and temporal scales, with user-defined months, years, counties, and watersheds.

  • SWMP Quick Start Guide, PDF (124 kb), Video
  • Executable and supporting database (.zip compressed file), version 3.0 (8.9 mb)
  • User’s manual, PDF (1.2 mb)
  • Technical Reports
    • Analysis Report, PDF (1.1 mb). Yuzhou Luo, Xin Deng, Robert Budd, Keith Starner, Michael Ensminger. 2013. May 28, 2013.
    • Analysis Memo, PDF (536 kb). Yuzhou Luo, Michael Ensminger, Robert Budd, Xin Deng, and April DaSilva, 2014. II: Refined Priority List.
    • Analysis Report, PDF (763 kb). Yuzhou Luo and Xin Deng, 2015. III: Watershed - Based Prioritization.
    • Analysis Memo, PDF (471 kb). Yuzhou Luo, Michael Ensminger, Robert Budd, Dan Wang, Xin Deng 2017. Methodology for prioritizing areas of interest for surface water monitoring of pesticides in urban receiving waters of California.

PREM (Pesticide Registration Evaluation Model)

The Pesticide Registration Evaluation Model (PREM) is used by DPR's Surface Water Protection Program (SWPP) to evaluate aquatic impacts of pesticide products submitted to California for registration. PREM assesses potential risks of products to adversely affect aquatic and benthic organisms thereby allowing SWPP to protect the environment & human health. The earliest version of PREM was released in 2012. It continues to evolve to better fit California conditions. New versions of the model are developed to incorporate major improvements in modeling capabilities. All posted versions are summarized as follows (please note that version 1 was only for internal development and test only and thus not listed below):

SWPP continues to improve the model's capabilities and specificity to California conditions. The following development has been completed, and will be incorporated into the model soon:


For content questions, contact:
Yuzhou Luo, Ph.D.
1001 I Street, P.O. Box 4015
Sacramento, CA 95812-4015
Phone: (916) 445-2090
E-mail: Yuzhou.Luo@cdpr.ca.gov