AWWA WQTC52877

New research indicates that ultraviolet (UV) disinfection holds great promiseas a cost effective disinfection alternative, but many implementation issues remain unresolved. Chief among these are the long-term performance (operations and maintenance) and reactor validation (assessment of delivered UV dose). Typical UV reactor validation methods involve performing bioassays with surrogate organisms. However, there still remains some question about the validity of these surrogate test data as long as simultaneous testing data is lacking to support its applicability to inactivation of target pathogens. During this study, a side-by-side live Cryptosporidium (the real target) challenge and MS-2(the surrogate) bioassay test was performed to directly link MS-2 surrogate inactivation to Cryptosporidium oocyst inactivation. In addition, this test fills a gapin the existing flow-through reactor dataset. Performance of the test will verify the efficacy and practicality of low-pressure UV lamp technology on Cryptosporidium inactivation in a flow-through reactor. This paper provides an assessment of the results of the MS-2 and Cryptosporidium bioassay, and the significance of these results for full-scale installations in terms of reactor UV dose validation and performance monitoring. In addition, the validity and appropriateness of each of the techniques for reactor validation are discussed. Includes 9 references, tables, figures.