A 60-Year History of the Efficacy of Polyethylene Encasement of an Iron Pipe Installation in an Aggressive Soil Environment

The Lafourche Parish Water District #1 (LPWD#1) has had an ongoing research project with the Ductile Iron Pipe Research Association (DIPRA) through the periodic evaluation of a four-inch cast iron water main in our system. Installed in 1958, it was the first known pipeline to use polyethylene encasement as a means of corrosion control. Over the past 60 years, the LPWD#1 has cooperated as DIPRA conducted field examinations of the pipe in an effort to evaluate the effectiveness of the film. In that time, some 10 investigations have been performed, with the most recent occurring in August 2018—after 60 years of service. Here, we summarize the results of those investigations, which culminated in the 60th-year investigation detailed in this report.