Clean Water Information and Resources

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Fresh water is one of the world’s most vital resources. Water quality is directly related to the quality of life, as we rely heavily on water daily to produce our food and energy. A polluted water supply can result in devastating effects on human health. Therefore, it is necessary to understand the importance of water testing and the environmental impact of low-quality water.

Water Quality Basics

Water quality is defined as the measure of the suitability of water for a certain use based on biological, chemical, and physical characteristics. To determine the quality of water, researchers need to analyze and measure water characteristics such as bacteria count, dissolved mineral content, and temperature. Scientists work to determine the levels of common constituents in the water like calcium, bicarbonate, sodium, and chloride, which are not typically harmful to human health. However, when trace elements like arsenic, chromium, and selenium are found in water, steps may be necessary to improve water quality in order to prevent adverse effects.

Contaminants can access the water from manufacturing processes, agricultural practices, and sewer overflows. When pesticides, fertilizers, and naturally-occurring chemicals end up in the water, several health issues can result, including reproductive problems, neurological disorders, and gastrointestinal issues. The elderly, young children, and pregnant women are especially at risk for becoming sick after drinking water that has been contaminated.

Guidelines and standards regarding water quality have been put into place to protect water for drinking, irrigation, recreation, or the maintenance of aquatic life. The U.S. Environmental Protection Agency has established standards for drinking water quality to ensure that public water supplies are safe for human consumption. Other standards have been put into place to protect wildlife, including fish and animals that eat aquatic life, such as birds.

Safety for Public and Private Drinking Water Systems

In 1974, the U.S. Congress passed the Safe Drinking Water Act. This law has worked to protect the public drinking water of the U.S. by allowing EPA to set drinking water quality standards. The EPA also oversees the localities, states, and water suppliers who are responsible for implementing these standards. The law was later amended to protect drinking water and its original sources, including lakes, rivers, springs, reservoirs, and ground water wells.

People who get their drinking water from a municipal or public supply have greater protection than homeowners with a private supply because their water safety is governed by legal standards. Water supplies are also tested on a routine basis dictated by the population size. However, even people with public supplies may need to test their water if their household plumbing contains brass fittings or lead pipes, as the possibility exists for contaminants to enter their home’s water supply.

Homeowners with private drinking water systems such as a well or surface water impoundment serve as their own water safety regulatory agency. These residents will be responsible for the quality of water that their family consumes. Periodic testing is recommended since the signs that drinking water is contaminated aren’t always obvious, as contaminated water may not smell, taste, or appear any differently than safe drinking water.

Water safety can be tested by a regional or local office of a state’s Department of Public Health, or by a private laboratory. In the State of Illinois, for example, residents can take a sample of water in a sterile bottle before dropping off the sample at their local public health office. Upon request, the Illinois Department of Public Health can also collect the sample. Local engineering firms and water-treatment companies may also be able to test your water, but it is usually recommended that homeowners choose a private or public lab that doesn’t sell water-treatment products.

Testing Water Quality and Safety

Scientists perform a variety of tests in order to determine water safety. These tests measure a variety of important factors to determine the suitability of water for its intended function, whether that is for humans to drink, agriculture, or animal habitat:

  • Temperature: Scientists use water temperature to determine the types of animals that can survive in a habitat and to get a better understanding about water chemistry.
  • Dissolved oxygen: This test tells researchers how much oxygen is available for aquatic organisms and fish to breathe.
  • pH: Researchers determine pH to learn the concentration of hydrogen in water, as highly acidic water could be deadly to aquatic life.
  • Nutrients: Scientists will measure phosphorus and nitrogen levels to determine whether they are appropriate for the growth of healthy aquatic life.
  • Bacteria: Scientists may test for bacteria that can be found in the intestinal tracts of humans and animals, which are known as fecal coliforms. The presence of these bacteria could suggest animal waste or failing septic systems have affected a water source.
  • Toxic substances: Toxic substances in water could be harmful to plant and animal life, including oil, pesticides, or metals. Mercury that comes from mining and pollution is being found in fish, which can later be ingested by people if the fish are caught and eaten.

While direct sampling is important in testing water quality, it is not the only way that scientists gain information. Satellite and aerial photographs and observations of the surrounding environment are also crucial in measuring water quality.

Water Safety and Environmental Concerns

Dirty water is the world’s greatest health risk, and it threatens public health in the U.S. as well as the health of the environment. When water from melting snow and rain runs off roofs and streets and into the river, it picks up toxic chemicals, trash, dirt, and disease-carrying particles along the way. Many water resources also lack protections that make them vulnerable to pollution from activities like fracking, industrial plants, and factory farms. These issues can lead to plant and animal habitat degradation and the contamination of drinking water.

Recent studies of waters in the Midwest have shown that a wide variety of unregulated chemicals are ending up in rivers and lakes, including insecticides, pharmaceuticals, fire retardants, and fragrances. Many of these substances are known to interfere with the functioning of hormones in people and animals. Air pollution, agricultural runoff, and wastewater discharges are all sources of these chemicals in water, and additional safety precautions are needed in order to prevent further water contamination.