Are Farmers Killing Our Water Supply?

Water waste and contamination from fertilizer, pesticides, and herbicides cause major problems for the environment
Are Farmers Killing Our Water Supply?


72 percent of the nation’s rivers are contaminated by agricultural practices, 26 percent specifically by pesticides.

This is one in a series of stories; visit The Daily Meal Special Report: Water for more.

When we talk about the impact of industrial farming practices, the conversation has a tendency to gravitate toward topics like organic growing practices, the use of antibiotics on livestock, and genetically modified foods. However, the impacts of industrial farming are far more complex and we rarely consider the impact that large farms have on our water supply.

There is no set definition for an industrial or factory farm. In general, these types of farms raise large numbers of animals or crops with a very limited amount of land and other resources and they use labor-saving practices like spraying pesticides and harvesting with heavy machinery to do so. Farms that operate this way have a tremendous impact on our water; they often use water wastefully and are the largest contributor the problem of its contamination. Not surprisingly, concerns about the dramatic and lasting impact of industrial agriculture on our ability to produce food sustainably continue to grow. 

A study conducted by the United States Environmental Protection Agency (EPA) found that 72 percent of the nation’s rivers are contaminated by agricultural practices, 26 percent specifically by pesticides. In this report, the EPA concluded that “agriculture is the leading source of impairment in the Nation’s rivers and lakes.”

Then there's simple water waste. The United Nations Food and Agriculture Organization (FAO) published a paper on the topic of water waste by farms, which concluded that “agriculture is single largest user of freshwater resources, using a global average of 70% of all surface water supplies.” That percentage is even higher in the U.S. The United States Department of Agriculture (USDA)’s 2012 report on Agricultural Resources and Environmental Indicators states that, in the United States alone, “agriculture is a major user of ground and surface water… accounting for approximately 80 percent of the Nation's consumptive water use” — or water that is not quickly returned to the environment. It is estimated that 60 percent of the water used by agriculture is wasted.

The majority of water wasted by industrial agriculture is wasted as the result of poor management and planning; farms that fail to tailor their practices on a case-by-case basis use far more water than they need to. For example, farms that use automatic flushing systems to clean out livestock stalls use 15 times more water than one that monitors need and modifies flushing accordingly. The same applies to irrigation systems; poor decisions about when to apply water and in what quantity account contribute to the overuse of this valuable resource.

Industrial farms not only use too much water, they have a significant impact on water quality because of fertilizer, pesticide, and herbicide runoff. One of the main problems is that large farms produce more animal waste than they can use; the United States alone produces 335 million tons of manure per year.  This waste is stored in “lagoons” (which often leak or overflow) until it can be used as fertilizer. This excess of available fertilizer often leads famers to over-fertilize their fields, applying more fertilizer than the soil can absorb. When the soil is saturated, the excess fertilizer runs off into nearby bodies of water or seeps into wells and other sources of groundwater. Fertilizer introduces phosphorous and nitrogen into water, both of which encourage plant growth. While that may be good when applied to a farmers’ fields in moderation, it’s not healthy for our water supplies; excess phosphorous and nitrogen encourage what is known as algal bloom) and this excess underwater plant growth can affect the water’s pH balance, making it undrinkable. Fertilizer also introduces ammonia, which can be converted into harmful nitrates, into our water. Drinking water with high nitrate levels has been linked to a number of human health concerns, including some that are fatal in infants. And, depending upon how an animal was raised, fertilizer runoff can introduce harmful pathogens and pharmaceuticals into drinking water as well.

Much like fertilizers, pesticides and herbicides are often applied to fields in excess, causing them to seep into groundwater or run off into nearby bodies of water. But chemicals sprayed on fields can also be carried by the wind, contaminating bodies of water hundreds of miles away.   

The majority of the water-related problems created by industrial farms come from mismanaged agriculture: poorly timed and applied irrigation water, fertilizer, and pesticides. Together they waste and degrade our already scarce water supply. With more than one fifth of the world’s population living in water scarcity, it is critical that we seek new and innovative solutions to the problem of agricultural water waste and contamination. The United States Agricultural Act (often referred to as the “Farm Bill”) of 2014 allocates only 6 percent of its funds to conservation, and only a limited amount of those conservation dollars will be dedicated to water.

There are a few things you can do to help. Write a letter to Congress letting them know that you think more government dollars should be allocated to the conservation of water; support small, local farms that use responsible methods to produce food; and purchase foods that require less water to grow, which means eating more plant-based foods. These are simple, small actions you can take today to make a difference worldwide.

Agricultural Runoff Threatens Fresh Water

Kristie Collado is The Daily Meal's Cook Editor. Follow her on Twitter @KColladoCook.