Water supply Maria Enzersdorf secured for the next decades

The pipeline between the Südstadt Federal Sports Centre and the elevated tank “Kleiner Rauchkogel”, with a total length of about 3.3 km, was rehabilitated over the course of several years and in several sections. RTi Rohrtechnik Group was commissioned with the rehabilitation of 450 metres.



Approximately 60 years old, the pipeline, which had been built by the predecessor organisation “Wassergenossenschaft Maria Enzersdorf” and later taken over by EVN Wasser, had to be renovated as a precautionary measure due to its age.

The supply of drinking water is an essential part of the daily quality of life and therefore of great every-day importance for the population of Maria Enzersdorf. In the summer, up to 15 million litres of drinking water are pumped through the pipeline of Maria Enzersdorf every day to ensure the water supply of this market town and some of the neighbouring communities. Timely rehabilitation of the pipeline is therefore a major concern for EVN Wasser.


EVN contracted the pipe rehabilitation specialist RTi Austria from Upper Austria to rehabilitate the last sections, amounting to a total of 450 metres.

Relying on trenchless rehabilitation technology, RTi used a pipe lining method with a fully load-bearing pressure pipe liner. This technology is based on a coated needle felt hose, which is impregnated with epoxy resin. The impregnated liner is inserted into the existing pipe by a special machine using compressed air in a reversion process and then cured with superheated steam. The cured liner is independent of the old pipe and can withstand internal pressure and external loads independently.  In addition, some preparatory and follow-up work was also carried out. Before the start of the rehabilitation work, the pipes were cleaned with ultra-high pressure cleaning systems and deposits were ground off with a special robot.

“Trenchless technologies represent an excellent alternative to conventional (open) construction methods and offer an environmentally friendly solution to rehabilitate pipelines quickly, efficiently and sustainably without excavation work,” Tobias Silberbauer, RTi Austria GmbH Project Manager, sums up.


The construction site was located in Franz-Josef Straße and Lichtenstein Straße in the area of the Maria Enzersdorf elementary school. Due to the proximity of the primary school and a bus station, even greater attention was paid to safety measures.

In order to minimise the size of the excavation pits as much as possible, two installation schemes were combined into one section and installed with an overlength.

During the rehabilitation project, slight gradients and several mitre arches had to be taken into account.

The RTi Group, which has more than 35 years of experience in pipe rehabilitation, mastered the challenges effortlessly.


The pipe rehabilitation specialist RTi successfully completed the rehabilitation of the drinking water pipeline at the end of March 2017.

The overall rehabilitation of the water pipeline is thus complete and the water supply for the population of Maria Enzersdorf is secured for decades to come.