Pesticide is the generic name for a group of chemicals designed to kill, inhibit, or repel weeds, insects, fungus, and rodents from bothering, eating or damaging crops, livestock, humans, or items that humans utilize. Pesticides include herbicides, insecticides, fungicides, and rodenticides and can also be placed within two other categories; Agricultural (crop, aquaculture, and livestock), and urban (home, garden, and yard, right-of-way, business, and industrial) applications. Specific pesticides have physical and chemical properties that result in their release and concentration or dispersal into groundwater resources.

Pesticides and Groundwater

Once pesticides are introduced into the environment, they are mobile and can travel far beyond their application or release.

Pesticides can find their way into groundwater through a variety of ways: leaching into the soil from direct application, accidental spills and leaks, improper storage or disposal and injection through wells or pits, such as those used to dispose of agricultural or urban runoff. Pesticides can also get into groundwater through seepage of contaminated surface water or through unplugged abandoned water wells.

Concern about pesticides in ground water is especially acute in agricultural areas, where most pesticides are used, and where more than 95% of the population relies upon ground water for drinking water. However, pesticides can also get into groundwater in urban areas through landscaping and home use. Both state and federal monitoring confirm the presence of pesticides in groundwater in Texas.

The Texas Commission on Environmental Quality (TCEQ) developed and maintains the Interagency Pesticide Database (IPD), which compiles all of the groundwater samples in the state for which pesticides have been analyzed. As of February 2022, the IPD contained data provided by nine agencies and other entities for over:

  • 388,000 pesticide analyses;
  • 15,000 groundwater samples; and,
  • 6,800 water wells and springs.

Although the IPD itself is not yet available on the TCEQ website, a map and draft report are available.

  • Texas Water Development Board's (TWDB) Groundwater Data page
  • The Texas A&M AgriLife Extension Service on-line Bookstore offers a number of publications on pesticides - from application and safety issues to agricultural use. Hard copies or free electronic downloads of these publications are available after setting up an account.
  • Tex*A*Syst also provides a number of great resources for handling pesticides safely, reducing groundwater contamination, and maintaining wells.
  • U.S.Geological Survey's National Water-Quality Assessment (NAWQA) Pesticide National Synthesis Project

Pesticides and Health

Pesticides and Agriculture

Groundwater White Papers

Groundwater Frequently Asked Questions (FAQs)

Frequently Asked Questions (FAQs)