Hot Tapping Facilitates 36-Inch PCCP Condition Assessment as a Sustainable Approach to Save $15 Million in Immediate Maintenance Expenditures

As the need for making better use of resources becomes more acute, hot tapping can facilitate access to pipelines for the introduction of devices to perform condition assessments without interruption of operation and services. Sets of assessment data can serve as a basis for more effective and sustainable solutions for pipeline maintenance or repair programs when a first set of data is used as baseline reference against data of later assessments to estimate the rate of deterioration occurring in the installation. The rate of deterioration can be used to establish a rational and more sustainable risk-based approach for maintenance and repairs, focused on distress locations, rather than a complete replacement of a pipeline approach based on an expected service life projection. The purpose of the paper will be to provide an illustrative case study of the organization, execution, and summary of the results of an initial in line condition assessment of several miles of 36-inch prestressed concrete cylinder pipe (PCCP), located in a congested urban area, which was accomplished with a free-floating device, facilitated by hot taps at the points of entry and retrieval. Projects using this type of procedure can provide the assessment data needed to define the first phases of a pipeline maintenance program.