This Old Pipeline: The Assessment of a Century Old Steel Pipeline

This paper presents an approach to evaluate a steel penstock over a century old using initial analyses to identify areas of the pipe that are most susceptible and most impacted by different types of threats to the penstock’s integrity. This starts with understanding how the asset was designed, constructed, operated, and maintained through its life and the available repair and rehabilitation methods. The paper will cover the available information, including historic design, fabrication, and construction practice; the analyses performed under this project and how they were used to support decisions regarding condition assessment methods and limits; the findings of the condition assessments; and lessons learned. Experience and lessons learned from other steel pipeline evaluations that influenced the approach taken for this project will also be presented. The benefits of a programmatic condition assessment approach are reviewed. Penstocks are a specific type of high-pressure pipeline intended to feed a hydroelectric facility for power generation. The presented approach for this penstock is applicable to other steel pipelines of a variety of vintages, including raw water conveyance and potable water transmission lines.