Water Purification in Standard Construction
Poor indoor air quality is not the only form of pollution that affects human health. Our water sources, both public supplies and private domestic wells, have also become increasingly contaminated. Public concern about water quality has increased dramatically. In late 2005, the Environmental Working Group (EWG) found in an analysis of more than 22 million tap-water quality tests (most of which were conducted to meet EPA compliance) that 260 contaminants were detected in water served to the public.1
Of the contaminants identified in the EWG study, the EPA has set enforceable health limits for 114 contaminants and nonenforceable, recommended standards for five. More than half (141) of the total contaminants identified are unregulated and without safety standards. The statistics reported by EWG are believed to represent an underestimate of the exposure of American consumers to unregulated contaminations in the nations tap water. Not considered in the study were unregulated pharmaceuticals and personal care product chemicals, which, surprisingly, were found in the tested water. The good news is that EWGs analysis found over 90 percent compliance with enforceable health standards.
Water purification is not standard in home construction, and unless you specify water testing and purification they will not be included. Although water purification is usually considered an “extra,” whole-house systems are best planned for and installed at the time of construction. But before you can contemplate options for water quality improvement, you need to know what is in your water.
This is relatively easy to determine if you are on a city or other public water system, but water in private wells is not regulated. The Safe Drinking Water Act (SDWA), passed in 1974 and amended in 1986 and 1996, gives the
Environmental Protection Agency (EPA) authority to set drinking water standards for public water systems that provide water for human consumption through at least 15 service connections or regularly serve at least 25 individuals. To find out more about regulated water contaminants and to learn about the potential health effects and the sources of these contaminations, consult the EPAs Drinking Water Contaminants website.2
There are two categories of EPA drinking water standards: primary and secondary. Primary standards (NPDWRs) are legally — enforceable standards that apply to public water systems and are classified into the following categories: microorganisms, disinfectants, disinfection byproducts, inorganic chemicals, organic chemicals, and radionuclides. Primary standards protect drinking water quality by limiting the levels of specific
