Are you concerned about your drinking water? Maybe it smells or tastes funny or perhaps the water is not clear. If so, you are not alone.
This is due to the Safe Drinking Water Act (SDWA) of 1974 and 1986, setting minimum water quality standards for all water utilities that serve at least 25 people or 15 service connections. These standards limit the allowable amount of pollutants found in drinking water measured in Maximum Contaminant Levels (MCL's). MCL's are measured in parts per million or parts per billion and are substances we can't see.
The problem is there is no guarantee that all utilities comply with regulations. Enforcement is difficult on national, state and local levels, and all testing isn't necessarily accurate. Water quality can vary from day to day, and testing might give erroneous results.
Through the SDWA, the Environmental Protection Agency (EPA) is empowered to regulate water quality. The EPA set guidelines for contaminants, which affect health and contaminants, which are aesthetically displeasing, but not harmful. The EPA identified hundreds of toxic substances yet water suppliers are required to test only a few. The water is usually tested at the water plant before distribution, but impurities can be picked up on the way to your faucet.
Only 1% of the Earth's water is fresh water that we can drink. This 1% can be contaminated by:
When water leaves the water plant, the contaminants are either removed or their levels were reduced to meet EPA standards. Water can become contaminated on the way to your home. Lead and asbestos-cement pipes can allow harmful substances to leach into the water. Even chlorine which is used as disinfecting agent, can react with organic materials in water such as decaying leaves and branches, and create Trihalomethanes (THM's), which are known to be carcinogenic. Older homes have lead pipes, which can allow lead to leach into the water.