When our current inner-city infrastructures were initially built, construction sites needed to employ a large number of people to get the work done. Trenches were excavated manually, pipes were lifted into the trenches without lifting equipment, and huge volumes of sand and filler material were placed back into the trenches by hand.
The most commonly used pipe material was cast iron; the pipe joints were tied off with hemp and sealed with lead.
Today, over 100 to 120 years later, the original pipe networks are in dire need of renovation and replacement.
In urban streets that were previously populated only by pedestrians and the odd vehicle belonging to a member of the wealthier classes, multiple lanes of dense traffic now thunder over the road surface; cars park along the sides of the road, forcing delivery vehicles to stop in the flow of traffic and causing further hindrance to road users.
If the essential renovation and replacement work were to be carried out in this kind of environment using a traditional open trench procedure, the transport system would collapse entirely – and the public would have to bear the costs of the resulting delays, exhaust gas and noise emissions and financial losses due to public transport delays.
It was with this kind of situation in mind that the urban centres of industrial nations started – as many as 30 years ago – to develop trenchless pipe installation procedures, initially to replace old drainage channels and to build new drainage systems, which are generally located under the surface on the lowest pipeline level.
These developments soon branched out to the replacement and renovation of drinking water and gas pipelines too. The new technology snowballed, creating a new segment for trenchless construction with its own special machinery, construction processes, technical standards and, of course, pipes that were suitable for this type of trenchless installation procedure.