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The WELL Building Standard™ (WELL) promotes safe and clean water through the implementation of proper filtration techniques and regular testing in order for building occupants to receive optimal quality of water for various uses.

Clean drinking water is a prerequisite for optimal health. Drinking water contamination is a major public health issue. The World Health Organization (WHO) reports that almost one billion people lack access to safe drinking water worldwide, and two million annual deaths are attributable to unsafe water, sanitation and hygiene.

The source of water contamination can sometimes be traced back to industry and its related processes. Contaminants like lead, arsenicglyphosateatrazine and microbes that are naturally occurring or inadvertently introduced into the water can pose serious health threats. However, treatment and distribution systems meant to keep our drinking water safe are also potential sources of contamination. For example, chlorine and chloramine which are commonly added to water to kill pathogenic organisms can lead to the formation of disinfectant byproducts such as trihalomethanes (THMs) and haloacetic acids (HAAs), as well as N-nitrosodimethylamine (NDMA), which may lead to cancer and other adverse health effects when exposure occurs at levels above the EPA standards. Finally, pharmaceuticals, personal care products (PPCPs) and other emerging contaminants are increasingly finding their way into our water supplies, with largely unknown health effects.

The quality of the U.S. surface water relies largely on The Clean Water Act of 1974. The U.S. Environmental Protection Agency (EPA) works to implement this Act and others (namely, the Safe Drinking Water Act), and publishes threshold concentration standards for water contaminants. These limits are set based on the likelihood of the development of cancer and other adverse health effects after long-term exposure to the specified contaminants. Nevertheless, drinking water contamination is a persistent problem. In a 2009 report, the EPA warned that “threats to drinking water are increasing,” adding that “we can no longer take our drinking water for granted.”

While taste and aesthetic preferences lead many people to drink bottled water, consumption of bottled water is not without its drawbacks. Overreliance on bottled water has environmental implications, but even putting aside those concerns, the quality of bottled water is subject to degradation. In one study, levels of antimony in 48 brands of bottled water from 11 European countries increased by 90% after 6 months of storage due to antimony leaching from polyethylene terephthalate bottles (PET(E) bottles, designated as recyclable “1”).

The same standards for quality are typically applied across all uses of potable water. This can result in a significant waste of resources, since each use does not require the same level of protection. The WELL Building Standard® seeks to simultaneously preserve this resource while enhancing its quality for human health in the context of different uses. Therefore, WELL requires a broad initial assessment to evaluate a building’s water source. From there, filtration can be installed to meet the thresholds required for each use. Buildings can continue to perform periodic testing to maintain quality water over time.


To read more about the WATER requirements of WELL, Click Here