Frequently Asked Questions

Q:  Doesn't the EPA do a good enough job setting standards to make my water safe?

A:  No easy answer.  Most EPA standards are based on contaminant levels considered safe for a 154 lb. adult male.  Those compounds known to affect children radically different than adults, such as nitrates and lead, have different, usually more restrictive, standards. Either way, some question whether EPA levels are safe for them. 

Also, by law, when determining a standard level, the EPA must take into account the cost of achieving that level. Some standards therefore are more relaxed than some feel comfortable with, because the cost to municipalities to lower the contaminant level is judged to be too high to be worth it. For example, all carcinogens are automatically given a Maximum Contaminant Level (MCL) goal of zero, even though everyone knows that is unattainable, so the actual MCLs are a compromise.

The EPA has identified more than 700 toxic substances in random drinking water sampling, yet water suppliers are required to test only for the handful of contaminants listed by the EPA.

The few contaminants that are regulated by the EPA are given permissible levels based on the risk of death or disease of one in 100,000 or one in a million. Some people distrust such government-established levels.

The EPA governs the nation's public water supplies that have 15 or more hookups or those that serve 25 or more persons. Private wells and small systems are not monitored by the EPA.

Water quality can vary from day to day, so test results may be erroneously alarming or reassuring.

Q:  How does water become contaminated?

Chemicals that are dumped onto or pumped into the ground by industry can easily get into our water supply. There are an estimated 181,000 industrial waste sites, over 16,000 municipal landfills and 100,000 ruptured underground gasoline storage tanks in the United States that leak contaminants into our water supplies.  Agricultural pesticides and highway de-icing are among many other common practices that also can cause problems.

Water can become contaminated during its journey from treatment plant to home. Lead and asbestos-cement pipes, prevalent in miunicipal water distribution systems, can allow harmful substances to leach into the water. Even chlorine used to disinfect our water can react with naturally-occuring organic materials in water, such as from decaying leaves, and create Trihalomethanes (THMs), which are known to be carcinogenic.

Water can become contaminated right at home. Some older homes have lead pipes or use lead-based solder to join copper pipes. Both can allow lead to leach into drinking water.