AWWA JAW57691

Combined central treatment and distribution are relatively recent phenomena, having only become standard in the last century or so. Given that <1% of treated water is actually ingested, the concept of treating all of the water in a system to optimal drinking water specifications is becoming more impractical, especially in the face of increasingly stringent regulations, high costs, water quality deterioration during distribution, and reduced access to high-quality source water. The Safe Drinking Water Act has created special opportunities for small systems to use decentralized compliance through point-of-use (POU) and point-of-entry (POE) techniques to provide supplemental treatment for part of the delivered piped water. Two-tier water systems that include the use of POU or POE devices or possibly even bottled water provide a feasible and cost-effective means of delivering safe water to consumers. Community-managed decentralized strategies also offer small systems the opportunity to achieve safer, higher-quality drinking water than these communities might otherwise have had, more quickly and at reasonable costs. These alternative approaches create new logistic, management, compliance, monitoring, and regulatory oversight issues, but these are solvable. Most of the principles supporting decentralized solutions for small systems are also applicable to providing community-managed "beverage-quality" drinking water in much larger systems. For all water providers, decentralized and centralized treatment combinations represent a better use of diminishing water resources and limited finances. Includes 19 references, table.