Runoff and/or leaching can occur when pesticides are carried off the application site into water such as rivers, lakes and streams, wells, storm sewers, or into groundwater. Runoff/leaching can occur when too much pesticide is applied or is spilled on the surface, too much rainwater or irrigation water occurs in a short period of time, or highly water soluble pesticides are used.

To gain a better understanding of how, where and why water runs off and how to prevent pollution read the following UNL publications:

Targeting Watershed Management Practices for Water Quality Protection: a Heartland Regional Water Coordination Publication, RP195
An overview of how to target best management practices in watersheds or landscapes to maximize the impact of investments in water quality protection.  

Pesticides and Groundwater: An Applicator's Map and Guide to Prevent Groundwater Contamination (School of Natural Resources Web site contains index to county maps and PDFs)

• To learn about protecting water when using herbicides, refer to the "Environmental Considerations When Applying Herbicides" section of the Guide for Weed Management.

• Specific recommendations for atrazine were compiled by UNL, the Natural Resource Conservation Service and Nebraska Department of Agriculture, Recommended Atrazine Best Management Practices for Surface Water Quality.

• County specific information on the conservation of soil, water, air, and related plant and animal resources is available in the Electronic Field Office Technical Guide developed by the Natural Resource Conservation Service.

• To help identify the restrictions intended to protect water quality that can be found on pesticide labels, refer to a listing of water quality restrictions from the Nebraska Department of Agriculture.

Several means are available to help prevent runoff and leaching of pesticides including:

• The use of buffer strips to slow down runoff and allow pesticides to adhere to soil particles and plant tissue, thereby preventing contamination of water. For more details read the UNL Extension NebGuides: Planning a Riparian Buffer, and Installing a Riparian Buffer.
• The use of mixing/loading/cleaning pads to contain pesticides on the mixing/loading/cleaning site. For more details read the UNL Extension NebGuide: Cleaning Pesticide Application Equipment.
• Practicing proper disposal of excess pesticides and empty pesticide containers and good spill prevention habits. For more details see: Rinsing Pesticide Containers NebGuide
  PDF version (958 KB; 4 pages)
  Safe Transport, Storage and Disposal of Pesticides Extension Circular (381KB; 13 pg.)
  The Pesticide Container Recycling Program, on the UNL Pest Education Web site.

• The use of anti-siphon and anti-backflow devices when filling pesticide application equipment to prevent contamination of well or domestic water supplies.