Liner Strength Prevents Storm Pollution
CIPP lining manufacturers and companies have, almost since the technology was invented, laid claim to just how strong their liner materials are once installed. To some clients this has been seen as just ‘marketing.’ Well not any more.
Seven years ago Insituform Technologies Ltd. (ITL) undertook a pipeline rehabilitation project on the Isle of Man using a 4.5-mm thick standard, needle felt, resin impregnated CIPP liner to rehabilitate a deteriorated 225-mm diameter, clay, foul sewage pipe, part of which ran under the river bed close to the village of Laxey, located on the east coast of the island. Until recently, the pipeline operated as expected, passing flows out to sea off the harbor.
A major storm system passing over Isle of Man produced major rainfall, which caused the Laxey River to flow extremely fast. These flows were sufficient to scour the river bed to the point where the clay pipe and its concrete surround were exposed to the torrent at the point where it crossed the river. Cobbles and boulders brought down the river by the torrent crashed into the exposed pipe and its concrete surround, smashing it completely.
This was where the ITL Insituform CIPP liner came into its own. While the original concrete casing and the clay pipe were completely destroyed where it was exposed to the worst of the river flow, the standard Insituform CIPP liner held fast without noticeable damage. Not only did the strength of the seven-year old liner allow the pipeline to continue operating despite the terrible conditions, the fact that it did prevented a major pollution problem in the river. If the pipe had failed completely, foul water flows would have spilled directly into the river water. The polluting flows would most likely have continued for sometime, as the pipe break would not have been detected until the river flows had subsided sufficiently to expose the breach.
Commenting on the performance of the liner under the circumstances, Steve Knowles, of the Department of Transport for the IOM, said: “Had this clay pipe not been lined, we would have suffered a major pollution event during the flows caused by the storm. As it was, thankfully, this did not happen. To repair the pipeline, since we had no need to install over pumping we saved significant time and effort in the works to bring the pipeline back to a fit-for-purpose state of repair. The continuing presence of the liner also now reassures us that we have that little extra level of security on the pipeline at the river crossing point should anything similar happen in the future.”
For ITL, John Beech, Business Development Manager, commented: “We have always said that our liners were good even though perhaps some people thought this was just marketing talk. Now everyone knows it is not. Whilst we would not wish to see our clients put into a position where our products are tested in circumstances such as those recently found at Laxey, it is instances of this kind and the performance of the liners in such extreme conditions that reinforce our confidence in our products.”
This article was provided by Insituform Technologies Ltd.
