San Francisco Public Utilities Commission (SFPUC), a large water purveyor serving 2.4
million of wholesale and retail customers, has installed 32 miles of prestressed concrete cylinder pipe (PCCP) since 1967.
To help manage its PCCPs proactively, SFPUC has selected and worked with Olivia
Chen Consultants (OCC) to develop a Prestressed Concrete Cylinder Pipes Reliability
Enhancement Program (PCCP REP). The implementation of this program would prevent
catastrophic failures and extend the service life of these pipelines.
The project involved evaluation of the existing condition, potential hazards, and
criticality of the installed PCCP. It also included a study of the causes of PCCP failure
and failure modes, case history evaluation of other utilities' PCCP failures, and review of
the state of the art monitoring and repair technologies for the PCCP. In addition, OCC
has developed a method to establish priorities for monitoring its PCCP and a decision-making
logic diagram to assist SFPUC in developing the most cost-effective PCCP
maintenance program. This program can also be used by other large utilities in their
effort to monitor and maintain their PCCP cost-effectively with limited funding and staff
resources. Includes abstract only.