Date Available


Year of Publication


Degree Name

Doctor of Philosophy (PhD)

Document Type

Doctoral Dissertation




Civil Engineering

First Advisor

Dr. Lindell Ormsbee


Water distribution systems have changed the landscape of communities through two services: 1) providing water supply for domestic and industrial use, and 2) providing water required to fight fires. However, a substantial portion of the water infrastructure in the country, as many of other public assets built over 50 years ago, are now reaching the end of their useful life; which combined with rapid growth and changes in demographics have placed water distribution pipe networks at a state that requires revitalization. The aging infrastructure along with the growing threat of natural and man-made disruptions have led water utilities to place a greater emphasis on developing better strategies to minimize the impact on the system users when a failure event occurs (i.e., improve the reliability of the system).

The proposed segment-based analysis considers valve location to estimate the number of pipes taken out of service to seclude the initial pipe break or element failure. The objective of the assessment is to identify critical segments (i.e., smallest set of pipes that can be secluded using the closest isolation valves) and critical valves in a set of real water distribution networks.

The critical elements, the segments or valves that when taken out of service cause the greatest reduction in the supply delivered and the level of service provided, are identified using the performance metrics based on: loss of connectivity, and the failure to meet hydraulic and fire protection requirements. This type of assessment seeks to be a simple method to provide information on critical elements that considers the role of isolation valves, thus offering a more realistic view of the effects of a breakdown. This framework is then used to define valve locations that could offer the improvement in reliability for a given capital investment.

Digital Object Identifier (DOI)