AWWA WSC69992

This powerpoint presentation begins by providing a brief overview of Denver Water Pipeline Disinfection Practices. Principles of ozone disinfection of water mains are presented, along with a Denver Water applied research program that includes laboratory and pipe loop studies, and full-scale testing. Presentation conclusions indicate that: ozone provides a fast, effective method for disinfecting new or repaired water mains; a "flow-through" disinfection method using the "CT concept" is required due to rapid ozone decay rate; Denver Water's bacteriological pass rate for new water main installations is 84-88% for both ozone and chlorine; and, the use of pressure washing or pre-flushing is a critical step for proper disinfection of water mains. Includes tables, figures.