Holy Toledo! Condition Assessment of a WWII Era 78″ Raw Water Steel Pipeline

The main water supply for the City of Toledo (City) is a 9-mi long, 78-in. diameter steel pipeline that was manufactured and installed during WWII. This pipeline has been in continuous service since that time except for shutdowns for condition assessment/asset management purposes. The City has a second raw water pipeline, 60-in. PCCP constructed in the 1970s, but the focus of this paper is on the original 78-in. raw water main steel pipe. In 1992, after the pipeline achieved its original 50-year service life, various condition assessments commenced over the next 25 years. This paper will summarize the overall known condition of the pipeline considering this 25-year history of condition assessments. With the present condition of the pipeline understood, the City desired to know if the pipeline was still safe to operate or if it was nearing the end of its useful service life. The previous condition assessments, improvements, and repairs will be utilized to develop a condition assessment “scoring” which will include both technical as well as subjective criteria. This effort will lead to an asset management task that would then guide the City as how to proceed, e.g., repair, rehabilitate or replace the raw water main. A summary conclusion will be provided as to the next step that the City took regarding this important raw water main.