All Nebraskans are stakeholders when it comes to the well-being of the state's water resources. In addition, Nebraska's fish and wildlife rely on clean water to live. When using pesticides, you have a responsibility to keep Nebraska's water unpolluted and safe for all to use. Dutiful handling, transportation, application, storage, and disposal of pesticides is essential in preventing water contamination. Nebraska Extension's pesticide safety publications can help you in this effort.
Leaching and Runoff
Reading a pesticide's label is the first defense against leaching and runoff, which lead to the contamination of watersheds. The label is a legal document that provides specific information and instructions to help avoid these problems. Learn more about understanding a pesticide label from Nebraska Extension.
Some things to keep in mind:
- A pesticide's label specifies its maximum application rate. Applying more than this rate is illegal and can be a serious cause of leaching/runoff.
- Soil types vary greatly. Soil that is coarse or sandy tends to be more penetrable and is prone to leaching. Soil that is fine or high in clay tends to be less penetrable and is prone to runoff. Read more about soil structure from UNL Water.
- Ill-timed applications in relation to irrigation or rainfall can be culprits of leaching/runoff. Refer to the label for guidance and keep an eye on the weather forecast when considering an application. See also: Stormwater Management: Pesticide Use in the Lawn and Garden
- Many pesticides are toxic to fish and other aquatic life. Labels may include safety recommendations such as buffer strips to help avoid dangerous leaching/runoff. Read more about Planning a Riparian Buffer and Installing a Riparian Buffer from Nebraska Extension.
More Applicator Resources
OSU Extension Pesticide Properties Database – This page lists several hundred common pesticides along with ‘pesticide movement ratings’ and three key characteristics of each: soil half-life, water solubility, and sorption coefficient. A simple explanation of each characteristic is also included. Applicators can use the Pesticide Properties Database to compare how much risk different pesticides pose to surface and/or groundwater.
Applicator's Map and Guide to Prevent Groundwater Contamination – Select a county on the state map to view a detailed map of leaching potential in that county (in printable PDF format).
Nebraska Buffer Strip Program – Producers who enroll land adjacent to streams, ponds, and wetlands in the Nebraska Buffer Strip Program are compensated by NDA. Buffer strips reduce soil erosion and filter out agrichemicals, thereby protecting surface water. Everyone wins!
Fertilizer and Pesticide Containment – An introduction to the federal and state regulations on bulk pesticide container labeling and secondary containment/loadout of bulk pesticides and fertilizers. These complex regulations involve several government agencies, and flowcharts exist to help determine if and how they apply to you.
Safe Transport, Storage, and Disposal of Pesticides, EC2507 – Transporting, storing, and disposing of pesticides safely is critical to protecting Nebraska’s water resources.
Hazardous Waste Disposal – Nebraska does not have a statewide pesticide disposal program. This page lists commercial firms that can consult about the safe transport, storage, and disposal of waste/excess pesticides.
Regulatory and Data Resources
Pesticides of Interest – NDA is required to evaluate ‘pesticides of interest’ in surface and groundwater. Read the evaluation summary for Nebraska’s 88 ‘pesticides of interest,’ including two ‘pesticides of concern’—acetochlor and atrazine.
State Management Plan for Pesticides and Water Resources –
The process described here will be used as a guide for developing Pesticide-specific Management Plans (or PMPs) for protecting human and/or environmental health from unreasonable adverse effects of pesticides in water for specific, potentially more localized, situations that can’t be, or most likely won’t be, addressed by product label language approved at the Federal level.
Agrichemical Contaminant Database for Nebraska Ground Water – Extensive collection of agrichemical contamination data from well water sampling in Nebraska. Narrow your search by county, NRD, chemical, date, well depth and type, and more.
Nebraska Pesticide Use Trends – Trends in the use of various pesticides are one factor in determining the potential impacts of pesticides on water quality. Estimates of common pesticide use in Nebraska from the USDA National Agricultural Statistics Service (NASS) and the US Geological Survey (USGS) can be viewed here.
Clean drinking water is essential to healthy living. When contaminants, including pesticides, enter the watershed, the safety of both public and private drinking water is jeopardized. The EPA sets regulatory limits on the acceptable amounts of certain contaminants in public water supplies. However, private drinking water is not regulated by either state or federal drinking water mandates in Nebraska. According to the National Pesticide Information Center (NPIC),
Point-of-use devices like charcoal filters and reverse-osmosis treatments can be used to remove or minimize pesticides in drinking water. Explore UNL Water's Drinking Water and Water Wells section to find detailed information and resources about the protection of drinking water.
Atrazine is the most frequently detected pesticide in Nebraska's groundwater. Watersheds and community drinking water systems continue to be monitored for atrazine levels. The EPA provides oversight for these and other triazine-related assessments.
For Private Well Owners
Potential Well Water Contaminants and Their Impacts – A brief discussion of some common contaminants of well water (microorganisms, nitrate/nitrite, heavy metals, organic chemicals, radionuclides, fluoride), where they come from, and their potential impacts on human health.
Protect Your Private Well – An infographic with tips for keeping private water wells safe and remediating contaminated wells.
What to Do With Your Private Well After a Flood – Well and pump inspection, emergency disinfection of flooded wells, and sampling/testing of well water are discussed.
Nitrates in Groundwater
Widespread use of soil fertilizers over many decades has led to increasing nitrate levels in Nebraska's groundwater. Excess fertilizers from agricultural lands and residential areas are types of nonpoint source (NPS) pollution. Read more about NPS pollution and what you can do about it. Most Nebraskans rely on groundwater as the source of their drinking water. When nitrate levels in water exceed acceptable limits, the health and safety of those who drink it, especially children and pregnant women, are at risk. This danger has forced some communities to install expensive purification systems to keep residents safe.
- Activity for kids: Nonpoint Source Pollution Awareness: Word Search Puzzle
Bazile Groundwater Management Area
In 2011, four Natural Resources Districts (NRDs) and the Nebraska Department of Environmental Quality (NDEQ) teamed up to develop a management plan for combatting nitrate contamination in the Bazile Groundwater Management Area (BGMA). In 2016, the EPA accepted their plan, which became the nation's first groundwater management plan to receive funding through section 319 of the Clean Water Act.
“NDEQ hopes other NRDs and municipalities will use the Bazile plan as a template to develop additional groundwater management plans in the state and nation.”
The four NRDs and NDEQ share data from ongoing sampling and analysis in the BGMA, as well as evaluation of the project, with the public at area meetings and with producers at nitrogen certification classes. The NRDs' boards of directors also receive this information. The project's 20-year assessment plan exemplifies the need for long-term adoption of responsible practices to improve groundwater quality.
Groundwater Vulnerability Map
Historical detections of four corn herbicides in ground water compared to relative ground water vulnerability (alachlor, atrazine, metolachlor, and simazine). Data are from the University of Nebraska-Lincoln Conservation Services Division (CSD) (1999) and Nebraska (2000).
Nebraska Conservation and Survey Division. 1999. Pesticides and Groundwater: An Applicator's Map and Guide to Prevent Groundwater Contamination.