What Are the Causes of Impure Water?

Humans are vulnerable to water supply contaminants every time they run their faucets. The average American household consumes 350 gallons of water every day inside their homes, according to the DrinkTap.org website presented by the American Water Works Association. These everyday water needs raise the potential for exposure to hazards that lurk in oceans, reservoirs, underground wells and even household piping. Scientists and governmental regulatory officials spend considerable resources analyzing the causes of impure water in order to protect consumers.

Wells

• Rain replenishes underground water tables as the droplets seep into pores of dense rock. More than 15 million U.S. homes rely on private wells, the Centers for Disease Control and Prevention reports. Toxic runoff also gets absorbed into these underground layers of rock, causing harmful substances to infiltrate water sources. Pollutants include raw sewage from cracked septic tanks, gasoline leaks from underground storage containers, and pesticides used in landscaping.

Lead

• Water pipes breed dangers if corroded plumbing allows lead to enter tap water, posing the greatest risks to children and pregnant women. Common offenders are brass or chrome-plated brass fixtures that leach serious dosages into household water, especially hot water supplies, according to the U.S. Environmental Protection Agency. Homes built before 1986 have a greater chance of using lead pipes. EPA authorities advise letting water run through lead-based faucets a minute or two before consuming it.

Medications

• Consumers often pour unused medications in their sinks and toilets. Authorities warn that human and veterinary medicines, antibiotics, and hormones are appearing in public water supplies. This cycle starts when tablets and capsules flow through public sewers and undergo processing at sewage treatment plants. Treated water eventually is returned to rivers and lakes, and later is drawn back into public water supplies. DrinkTap.org recommends that consumers contact a local pharmacist for advice on discarding any medications.

Industry

• Industrial discharges are heavily regulated, but mishaps such as the Exxon Valdez oil spill in 1989 in Alaska can contaminate water sources. The Environmental Pollution Centers website warns that the cost of disposing of wastes can lead to temptations to dump it illegally. In addition, routine handling and storage of chemicals carries risks of those poisons seeping into soils or underground water supplies. Agricultural runoff generates pollution when fertilizers, pesticides, and insecticides creep into ponds and rivers, prompting algae growth that indicates high phosphate and nitrate levels in the water.