AWWA JAW65356

The link between the contamination of distributed water and the occurrence of operations and maintenance (O&M) activities in distribution systems (DSs) has mostly been based on specific cases resulting in waterborne disease outbreaks. It has also been possible to know the fraction of reported outbreaks, particularly in the United States, that can be attributed to DS deficiencies. However, without being in a situation of disease outbreak, water utilities can be faced with DS water quality variations such as the occurrence of coliform- positive samples, occurrences of heterotrophic plate count bacteria, and customer complaints. No specific study of the fraction of these water quality events originating from DS activities has been compiled. This research, using a data integration approach based on the simultaneous study of different types of historical databases, is a first step toward verifying and establishing such a link. The analysis shows that O&M activities can be related to water quality variations in various proportions, and some of the main causes of water quality changes are identified (e.g., pipe replacement and valve and hydrant operation). Water suppliers can apply this concept of data integration to assess their own systems. Includes 21 references, tables, figures.