Tap water is generally safe to drink in the US, but Americans can take additional steps to improve the quality of the drinking water and make it safer. A number of factors should be considered when talking about the safety of tap water.
Tap water in the U.S. is generally safe, but with some caveats.
While the U.S. has high standards for public drinking water, many substances can contaminate the water.
To make the drinking water safer, consider using a water filter, preferably using reverse osmosis technology.
The average American citizen consumes about one to two liters of drinking water per day, in addition to the water used for cooking or washing foods. Virtually all drinking water in the U.S. comes from fresh surface waters or groundwater aquifers and is tested according to high U.S. and international standards for making it safe to drink.
Health authorities regularly assess the quality of tap water. There are over 150,000 public water systems in the U.S. serving over 300 million Americans. The US Congress enacted the Safe Drinking Water Act (SDWA) in 1974, and this is the main federal law in America focused on the quality of tap water. The SDWA authorizes the US Environmental Protection Agency (EPA) to set national standards to tap water to protect Americans against health issues related to exposure to water contaminants.
Watch out for contaminants
According to the EPA, a variety of contaminants and pollutants can be found in tap water. Water contains small amounts of some contaminants, and the fact those contaminants are present does not necessarily mean that drinking water may be harmful. Tap water may cause health problems when certain contaminants reach a certain level in the water.
For example, in Flint, Michigan, there was a public health crisis back in 2014- 2016, which involved the municipal water supply system. Tens of thousands of local residents were exposed to dangerous levels of lead, and bacterial contaminants were responsible for sickening many and killing at least 12 people.
EPA has special regulation in place for more than 90 contaminants in drinking water. Water contaminants are broadly classified into:
- Physical contaminants like sediment or organic material from soil.
- Chemical contaminants, which can be naturally like minerals and toxins produced by bacteria, or man made like pesticides, plastic particles or drugs.
- Biological contaminants are microorganisms like bacteria, viruses, fungi and parasites.
- Radiological contaminants including cesium, plutonium and uranium.
More details on microbial contamination
While life threatening microbes responsible for cholera or typhoid fever are rare in the US and all Western countries, many viruses and other microbes can cause stomach pain, diarrhea, and vomiting. These infections are often self limited or require minimal treatment in healthy individuals, but can be severe and even life threatening for individuals with a weakened immune system.
Local health authorities issue warnings when dangerous levels of certain microbes are detected in the tap water and they may recommend boiling the water before consuming it, if necessary.
For example, bacteria like E.coli and parasites like giardia can leak from the sewage system into the drinking water. Food and other environmental contaminants are also reported to the public, along with recommendations on how to stay safe.
Water contaminants on the rise
In 2019, the Environmental Working Group (EWG) found 56 new contaminants in the drinking water in the U.S., which were added to the list of more than 300 known contaminants.
Many of these newly detected contaminants include various pesticides, disinfectant by-products and radioactive compounds. Some of these substances are associated with serious health conditions including cancer, reproductive disruptors and liver diseases. The EPA has not yet regulated these chemicals.
How to make tap water safer
While the U.S. has high standards for public drinking water, the regulation of the law in the U.S. is not perfect and it does not apply to homes that use private wells. EPA regulates over 90 contaminants, but a few more hundreds of substances found in the water should be monitored.
For these reasons, Americans can take a few additional steps to ensure the safety of the drinking water.
- Test your water. Most of the water contaminants can’t be seen with the naked eye, but fortunately can be tested. A variety of home test kits are available currently on the market. Some of them are basic kits testing for one contaminant such as lead and can be purchased from the local Home Depot for $20. Other tests like SimpleWater Tap Score Advanced City Water tests for more than 100 compounds including metals, volatile organic compounds, bacteria, industrial and agricultural contaminants and more.
- Individuals living in the U.S. can search the database from EWG and find contaminants in the local drinking water, by checking this link and typing in the zip code. You can also find the best water filters that can be used for those specific contaminants.
There are different types of water filters.
- Water filters based on carbon or activated carbon are often used to remove chlorine and improve the taste or odor, while some advanced filters based on this technology can also remove volatile organic compounds, asbestos lead and mercury.
- Water filters based on reverse osmosis have the ability to remove more contaminants, including arsenic, fluoride, hexavalent chromium, nitrates and perchlorate.
- Water filters using ion exchange and water filters reduce calcium, magnesium, barium and radium, with very little to no impact on other contaminants.
The EWG recommends using point- of-use filters and reverse osmosis technology for drinking and cooking water only.
The U.S. has high standards to evaluate and ensure safety of the drinking water. EPA has special regulation in place for more than 90 contaminants in the drinking water. However, more and more contaminants are found in the water and environment. Using quality water filters can further increase the safety of the drinking water.