AWWA QTC97174

Thames Water Utilities has operated a 1.3 km long, 100 mm diameter, once through pipe system since 1994 to study key factors affecting water quality changes through distribution networks. As part of these studies, water samples, pipe sections of various materials and coupons (iron and polyethylene) have been sampled from the supply tank and three points along the length of the pipe, to enumerate bacteria and determine adenosine triphosphate (ATP) levels. ATP has been used in many industries as a rapid measure of microbiological contamination and can be used to assess the potential of water to support biological growth. The study was conducted to compare traditional plate count testing with ATP measurements for biofilm and water samples and to assess the value of ATP measurements for determining biological activity in water distribution systems.