AWWA ACE59876

Under the Long-Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR), all utilities in the U.S. will receive ultraviolet (UV) disinfection credit using measurements made by UV sensors. Yet, performance issues exist with commercial UV sensors. Sensors are used within monitoring strategies that do not meet current guidelines, and current guidelines do not agree on criteria. The goal of AwwaRF project 2977, Design and Performance Guidelines for UV Sensor Systems, is to develop practical design and performance guidelines for UV sensors used for dose delivery monitoring by UV disinfection reactors. This goal will be met through a focused research approach that involves: benchmarking the state-of-the-art through a literature review and vendor survey; developing instrumentation for measuring UV sensor properties with different designs; measuring the performance of current UV sensors under field and laboratory conditions; analyzing the impacts of sensor properties on dose delivery monitoring using the latest in CFD-based dose and UV intensity modeling; obtaining feedback on draft guidance from stakeholders; and, implementing a NIST primary calibration and verification service for UV sensors. Specific deliverables will be a final report with the results from each task in our research approach, a software package for CFD-based dose and sensor modeling, and a NIST calibration and verification service for UV sensors. Includes 15 references, table, figures.