Maximizing Your Investment: An Incremental Approach to Assessment of Critical Large Diameter Transmission Mains

When New Jersey American Water (NJAW) experienced three failures on one of their major transmission mains, they faced the challenge of how to effectively and efficiently spend their budget to maximize the remaining life one of the backbones to their conveyance system. Recognizing that while the pipeline had previously failed, it may still have significant remaining useful life, NJAW embarked on a phased, incremental approach to assess the condition of the pipeline and ultimately make necessary improvements to the main, while maximizing the value of their investment. One of the most significant challenges was to determine if the pipe had a few isolated problem locations or if uniform deterioration existed, which caused the three failures. The flexible approach was structured to optimize the collection of pertinent data by using collection methods of increasing levels of resolution, such that once an adequate level of information had been collected, the process could be halted, and necessary repairs and improvements could be made. The intent was to develop a proven, repeatable process that could be used to assess all of their high-risk transmission mains. This paper will discuss the phased approach used by NJAW to confirm reliability of this pipeline for years to come.