30 YEAR POLYETHYLENE FIELD TRIAL
Assessing the risk of failure and remaining useable life of polyethylene water mains
Polyethylene potable water mains with an assumed minimum design life of 50 years have been in widespread use in the water industry for more than 30 years.
In the 1980s and 1990s Severn Trent Water in the UK buried two polyethylene pipe test beds in the Midlands. These two test beds near the pumping stations at Great Gates and Coopers Green, had all the pipe material analysed chemically and mechanically before installation. This was documented in several studies as well as the subsequent exhumations in the following years.
These reports showed that the pipe had not deteriorated significantly in the first 5 years
after installation.
These pipes have been exhumed and the tests repeated 30 years later. Analysis of these pipes showed that some of the newest PE100 pipes could last as long as 160 years. The variation in performance of early pipes compared to newer evolutions was also obvious from the results obtained.