the connection between agriculture and drinking water contamination

Agriculture and farming is an important and necessary means of survival and is pervasive in the environment we live in today. Without agriculture, there would likely be a scarcity of food throughout the world.

For thousands of years, many farmers relied on natural fertilizers like fish, manure, or ground bones. This natural agricultural process didn’t harm the land. However, modern agricultural practices have introduced pollution processes into the mix, sometimes causing land, ecosystem, and environmental degradation — as well as agricultural runoff in drinking water.

In particular, irrigation using contaminated water is a source of agricultural pollution. For instance, some of the water we use derives from canals, groundwater reservoirs, and rain. Although plenty of it is pure and clean water, some sources contain pollutants with heavy metals and organic compounds. This happens due to the disbursement and disposal of agricultural and industrial waste in local water bodies.

Take the instance with Ione Cleverley. She had a farmer-tenant who left her with unplanted fields. She then learned that every spring, as the soil moistened and warmed, it released nitrogen, which was both left over from the last synthetic fertilizer application and naturally occurring. The chemical washed into her stream by rain where it then flowed into the Skunk River and later the Mississippi.

Nitrogen converts to nitrate in water, where it presents two serious issues:

  1. Individuals who drink tap water contaminated by nitrate have increased health risks.
  2. Once nitrate gets to the ocean, it hyper-charges the growth of aquatic bacteria and algae that use up the water’s oxygen and leaves it uninhabitable for numerous sea creatures.

This is just one example of the agricultural runoff effects on water.

To help you understand more about the connection between agriculture and drinking water contamination, this guide explains:

  • How water is used on a farm.
  • The different types of agriculture pollution.
  • How contaminated water makes its way to your home.
  • The link between water contamination and your body.
  • How to protect you and your family.

How Water Is Used on a Farm

how water is used on a farm

Unlike pollution from point sources, such as sewage and industrial treatment plants, nonpoint source (NPS) pollution comes from many sources. How does agriculture contribute to water pollution?

Snowmelt or rainfall moving through or over the ground can cause polluted runoff. As the water moves, it picks up human-made and natural pollutants and carries them away where it then deposits them into watersheds through rivers, lakes, coastal waters, and underground drinking water sources.

Pollutants resulting from ranching and farming include:

  • Pesticides
  • Sediments
  • Metals
  • Pathogens
  • Salts

Implementing management practices adapted to local conditions can reduce agricultural activities that have an impact on ground and surface water. Numerous methods created to decrease pollution also save farmers money and increase productivity.

Types of Agriculture Pollution

Several different types of agricultural pollution exist today, including:

1. Sedimentation

Water can become clouded with too much sediment, reducing the amount of sunlight aquatic plants receive. It can also smother fish larvae and clog the gills of fish.

2. Nutrients

Farmers apply nutrients like nitrogen, potassium, and phosphorus in the form of manure, chemical fertilizers, and sludge. They might enhance production by growing legumes and leaving crop residues. When these sources exceed the needs of the plants or are applied right before it rains, the nutrients may wash into aquatic ecosystems.

They then can cause algae blooms, which can take away boating and swimming opportunities, remove oxygen from water which kills fish, and create odor and a foul taste in drinking water. High nitrate concentrations in drinking water can lead to methemoglobinemia, a disease that can potentially cause death in infants — also referred to as blue baby syndrome.

3. Pesticides

Farmers use herbicides, fungicides, and insecticides to kill agricultural pests. These chemicals may then enter the water, contaminating it through direct application, atmospheric deposition, and runoff. They can poison wildlife and fish, destroy animals’ habitat they use for protective cover, and contaminate food sources.

4. Irrigation

Inefficient irrigation can lead to problems with water quality. For example, in arid areas, where the rainwater doesn’t carry minerals deep into the soil, irrigation water evaporation can concentrate salts. Excessive irrigation may affect the quality of water by:

  • Transporting pesticides, nutrients, and heavy metals
  • Causing erosion
  • Decreasing the amount of water naturally flowing in rivers and streams

Excessive irrigation can also cause selenium buildup. Selenium is a toxic metal that could harm waterfowl reproduction.

5. Animal Feeding Operations

Farmers confine animals in small lots or areas to efficiently maintain and feed livestock. The problem is, these confined lots become huge sources of animal waste. Approximately 238,000 working ranches and farms in the U.S. are considered animal feeding operations and generate around 500 million tons of waste each year.

Runoff from poorly-managed facilities can carry pathogens like:

  • Viruses
  • Bacteria
  • Oxygen-demanding organics and solids
  • Nutrients

These can all contaminate fishing areas and create problems with water quality. Waste seepage can also contaminate groundwater. Farmers can use appropriate waste management systems to store and manage facility wastewater and limit discharges.

6. Livestock Grazing

Overgrazing by livestock can cause many problems including:

  • Increasing erosion
  • Exposing soils
  • Encouraging undesirable plant invasion
  • Destroying fish habitat
  • Destroying floodplain vegetation and stream banks necessary for natural water filtration

Farmers can decrease the impact of grazing on water quality in several ways. They can keep livestock out of sensitive areas, adjust grazing intensity, promote revegetation, and provide alternative sources of shade and water.

How Contaminated Water Makes Its Way to Your Home

how contaminated water makes is way to your home

Contaminated water can get into your home in several ways. Agriculture is the primary source of pollution in streams and rivers in the U.S., although wetlands and lakes can also be contaminated.

According to the U.S. Environmental Protection Agency (EPA), agriculture is the top cause of impaired water quality in the U.S. As a primary source of pollution of water, agriculture accounts for 70 percent of worldwide water withdrawals and plays a significant role in the contamination of water. Agricultural runoff flows into the rivers and lakes where many towns get their water supply.

Farms discharge huge quantities of organic matter, agrochemicals, sediments, saline drainage, and drug residues into water bodies.

In between frequent storms, ranchers and farmers have brief dry weather stretches that are just long enough for them to apply fertilizers and pesticides. And, each time it rains, animal waste from livestock operations and farms, fertilizers, and pesticides wash pathogens like viruses, bacteria, and nutrients into our waterways.

In many emerging economies and high-income countries, agricultural pollution exceeds contamination from industries and settlements and is now the primary factor in inland and coastal water degradation.

Uneaten feeds and fish excreta from fed aquaculture diminish the quality of water. An increase in production combined with greater use of fungicides, antibiotics, and anti-fouling agents contributes to the pollution of downstream ecosystems.

Agriculture affects water quality through surface water and groundwater.

1. Surface Water

Surface water covers around 70 percent of the earth and fills our lakes, oceans, rivers, and other bodies of water. Surface water from freshwater sources accounts for over 60 percent of the water delivered to homes in the U.S.

Almost half of our streams and rivers and over a third of our lakes are polluted, making them unfit for fishing, swimming, and drinking. Nutrient pollution, including phosphates and nitrates, is the main type of contamination in these sources of freshwater.

Although animals and plants require these nutrients to grow, they’ve become a considerable pollutant due to fertilizer and farm waste runoff.

2. Groundwater

When rain falls and seeps into the ground, filling the crevices, cracks, and porous areas of underground aquifers, it becomes groundwater. Almost 40 percent of people in the U.S. rely on groundwater, pumped to the surface of the earth, for drinking water.

Groundwater is the only source of freshwater for some people in rural areas. It becomes polluted when fertilizers, pesticides, waste, and other contaminants leached from septic systems and landfills reach an aquifer and render it unsafe for humans to use. Groundwater may also spread these contaminants far from the initial pollution source as it seeps into lakes, oceans, and streams.

The Link Between Water Contamination and Your Body

Contaminated water affects your body in several ways. Here are some of the contaminants and their effects:

1. Sedimentation

Higher levels of turbidity, or cloudiness, are frequently linked with higher levels of microorganisms causing disease like parasites, viruses, and some bacteria. These microorganisms can cause symptoms in humans such as:

  • Cramps
  • Headaches
  • Diarrhea
  • Nausea

2. Nutrients

Too much phosphorus and nitrogen in the water cause a faster growth rate of algae than ecosystems can handle. Substantial increases in algae can harm habitats and food resources, water quality, and reduce the oxygen aquatic life needs to survive.

Some algal blooms can harm humans since they produce bacterial growth and elevated toxins that can make you sick if you consume tainted shellfish or fish, come into contact with polluted water, or drink contaminated water.

Nutrient pollutants in groundwater can be harmful to the millions of individuals in the U.S. who use groundwater as their drinking water source. Infants are especially susceptible to nitrates in drinking water. Excess nitrogen in our atmosphere can create pollutants like ozone and ammonia which can limit visibility, impair our ability to breathe, and alter plant growth.

3. Pesticides

The type of pesticide, route, and duration of exposure and health status of the individual determines the potential health outcome. In the human body, as well as in animals, pesticides can be metabolized, stored, excreted, or bioaccumulated in body fat. Chemical pesticides have been linked with numerous negative health effects that are:

  • Gastrointestinal
  • Dermatological
  • Respiratory
  • Carcinogenic
  • Reproductive
  • Neurological
  • Endocrine

4. Irrigation

In the agricultural sector, wastewater is increasingly being used to cope with the freshwater source depletion as well as water stress associated with changing climate conditions. Exposure to wastewater has been linked to diseases such as:

  • Bacterial
  • Viral
  • Shigellosis
  • Salmonellosis
  • Hepatitis A
  • Cholera
  • Protozoan
  • Amoebiasis
  • Giardiasis
  • Other diarrheal diseases

5. Animal Feeding Operations

Public health concerns linked with concentrated animal feeding operations include an increase in the risk of pathogens passed from animals to humans, food-borne disease, the emergence of antimicrobial and antibiotic-resistant microbes largely due to widespread antimicrobial use for nontherapeutic reasons, and worker health concerns.

6. Livestock Grazing

When cattle have uncontrolled access to bodies of water, grazing areas, or intensively managed domestic pastures, they can contaminate them with sediment from damaged streambanks and manure.

Drinking contaminated water can cause illnesses known as “water-borne diseases.” Contaminants often found in urine and feces of animals can be bacteria like:

  • Campylobacter
  • Salmonella
  • Parasites like cryptosporidium and giardia
  • Viruses
  • E. coli
  • Toxoplasma

Water contaminated with feces and urine from infected domestic animals is what usually causes water-borne diseases.

7. Household Pollution

People’s homes contribute to nutrient pollution through yards, appliances, pets, and driveways. Roadside storm drains frequently lead directly to local rivers and streams, therefore anything flowing into them can make their way to local waterways. Residential areas can be a source of phosphorus and nitrogen fertilizer pollution.

To understand the steps to take to protect you and your family, first evaluate your situation. For instance:

  • Do you live near a factory or industrial site?
  • Do you use water from a well?
  • Do you have pets?
  • Do your neighbors use pesticides and fertilizers on their yards?

These all put you at risk in many ways.

Over-watering and over-fertilizing a lawn is common among landscaping services and homeowners. When a garden or yard is over-watered, fertilizer can wash away more easily.

Pet waste contributes to phosphorus, nitrogen, bacteria, and parasites to water bodies when it’s not properly disposed of. It can also lead to unsafe conditions in local bodies of water for human recreation.

Many laundry, car and dishwashing soaps contain phosphates — a form of phosphorus — which are carried from households through drains into the water system.

Using electricity in our homes also adds excess nitrogen into our atmosphere. Many electricity sources come from burning fossil fuels, which cause environmental pollutants.

How to Protect You and Your Family

protect your family from water contamination

You can take action to reduce or avoid pollutant exposure. To reduce your contributions to contaminated drinking water:

  1. Choose phosphate-free soaps, detergents, and household cleaners.
  2. Pick up your pet’s waste.
  3. Reduce your use of pesticides, fertilizers, and herbicides.
  4. Inspect your septic system yearly.
  5. Only run your dishwasher or washing machine when there’s a full load.
  6. Pump your septic system out regularly.
  7. Avoid walking your pet near waterways like streams or rivers. Instead, walk them in parks, grassy areas, or undeveloped areas.
  8. Use commercial car washes since they’re required to dispose of wastewater properly and many of them filter and recycle their water.
  9. Repair leaking toilets, faucets, and pumps.
  10. Talk to local legislators about contaminated drinking water.
  11. Support your local surface-water or local storm program.
  12. Carpool with coworkers or friends. 
  13. Unplug electronics when not in use.
  14. Filter your own water.

Filter Your Water With a Multipure System

filter your water with Multipure

You should protect your family, particularly if you live in a rural area or your water supply is near farms. You can take actions like those described above to decrease nutrient pollution through the choices you make around your home, in lawn maintenance, with your pets, and in transportation.

Another great way to reduce your risk of pollutant exposure is through water filtration. Multipure drinking water systems offer a cleaner and healthier solution for drinking water you access right at your kitchen sink. Our systems help reduce many contaminants that are unsafe and harmful for your health with a wide range of filtering products.

Multipure provides innovative filter technology with outstanding performance. Through Multipure drinking water systems, you can reduce contaminants like PCBs, MTBE, VOCs, chloramine, chlorination byproducts, and heavy metals. With our drinking water systems, you get tastier, cleaner, and healthier water.