Water Resources

Nutrient & Pesticide Management

Water contaminants or pollutants that impact the quality and/or use of water are generally subdivided into five major categories. One of these major categories is chemicals, which includes inorganic (non-carbon containing) and organic (carbon-based) chemicals. Nutrients are inorganic mineral elements that are absolutely essential for both plant and animal nutrition. Pesticides are either organic or inorganic chemicals, which are used to control weeds, insects and other pests. There is a growing concern for water quality problems associated with both nutrients and pesticides. The nutrients of primary water quality concern are nitrogen and phosphorus. Numerous pesticides are a potential threat to water quality.

Most people think of nutrients as the chemical fertilizers used in agriculture and of pesticides as those chemicals used specifically to control agricultural pests. Agriculture is the primary user of these products, but there are other uses for both groups of chemicals. We use fertilizers and pesticides on our lawns and gardens, on our playing fields, on rights of way, and even in our water supplies. We also use pesticides in our homes, on our pets and even on our own bodies for disease and health protection. Nitrogen and phosphorus are components of plant and animal waste products and both are now used in numerous industrial products and processes, some of which result in their release into the environment.

Without human influence, nitrogen and phosphorus are cycled regularly throughout our environment. The atmosphere we breathe is 78 percent nitrogen. Many of our newer pesticides are similar to naturally occurring chemicals which plants produce to ward off diseases or insect attack. However, humans have significantly impacted what were once natural nutrient cycles for nitrogen and phosphorus, so that more of each are finding their way into both surface and ground water sources. And, we have developed many synthetic pesticide chemicals, which unlike natural chemicals, do not readily degrade to harmless, nontoxic products within a short period of time. Thus, more of these products are finding their way into water sources as well.

Nutrient and Pesticide Management in Your Watershed:

Contaminated runoff from agricultural and urban areas where fertilizers and pesticides are applied and nutrients from human and animal wastes, are the primary sources for nutrient enrichment and pesticide contamination of both surface and ground water supplies. Progress has been made in cleaning up nutrients from point source discharges, but land application of plant, human or animal waste products can lead to nutrient enrichment from these sources. Since land use is the primary indicator of potential nutrient and pesticide contamination, and regular stream monitoring is the best method to monitor and assess impacts as well as restoration efforts-nutrient and pesticide managementprograms can best be implemented and monitored for success on a watershed basis.

To determine if nutrient and pesticide management is adequate in your watershed, you must first make some sort of assessment as to the type, volume and distribution of these products within the boundary of your watershed. You must then determine if these products are being properly managed and utilized at appropriate rates and under satisfactory conditions to reduce both point source and storm water discharges of excessive levels into the water supplies within your watershed.

A basic knowledge of the recommended best management practices (BMPs) for reducing nutrient and pesticide contamination of surface and ground water supplies will help you make your assessment and implement watershed-based pollution prevention programs. See below for where to find information about BMPs.

Resources and Programs:

A multitude of resources and programs are now available on proper management and use of nutrients and pesticides to prevent water pollution.

Auburn University Nutrient and Pesticide Management Team:

The EPA Office of Wetlands, Oceans, and Watersheds has best management practice documents and information on nonpoint source categories including agriculture, forestry, marinas, and urban.

Agriculture Pollution Prevention techniques

National Stormwater Best Management Practice Database