AWWA JAW68767

Utilities with uncovered finished water reservoirs face many water quality, security, and regulatory challenges. These utilities will need to provide covered storage or treatment to comply with the Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) requirements. This article provides an overview of the history of uncovered reservoirs, identifies drivers for improving protection of uncovered reservoirs, discusses options for compliance with the LT2ESWTR, presents an approach to decision-making regarding compliance, and presents case studies that demonstrate how utilities have implemented various compliance alternatives. A variety of cover and treatment options are potentially appropriate for LT2ESWTR compliance, and many evaluation criteria must be considered when selecting a compliance alternative. It is recommended that each utility determine, prioritize, and rank its alternatives based on criteria that are specific to its regulatory compliance and project goals. Typical evaluation criteria include regulatory compliance, water quality effects, site aesthetics, operations and maintenance requirements, vulnerability/ public safety, cost, permitting requirements, and design life. Includes 26 references, tables, figure.