AWWA JAW63841

Many engineers size an ultraviolet (UV) disinfection system based on design conditions of flow, UV transmittance (UVT), and lamp output, and then assess operation and maintenance costs based on average flow. However, flow and UVT vary among water treatment plants and response to these variables by the UV system varies among equipment. As a result of the limitations of this approach, many installed systems today are significantly overdosing. Simulations of the performance of UV system alternatives that account for critical variables provide the best foundation for selecting UV systems for drinking water applications. This article provides an overview of UV disinfection, identifying the benefits of applying the key features associated with dose monitoring, validation, and design and a new approach for integrating these factors to obtain optimal design. Includes 23 references, tables, figures.