Inverted siphons

Aarsleff Pipe Technologies is the world leader in No-Dig renewal of inverted siphons. Since the early 1980s we have renewed a large number of inverted siphons around the world. Actually, we have developed technologies and methods that we use today. We typically renew inverted siphons using Aarsleff CIPP Lining.

The process of renewing inverted siphons is very complicated. The planning phase is vital to the final result. In order to carry out a renewal process we need access to both ends of the siphon in question. Therefore an important part of the planning phase is to establish both a launching pit and a receiving pit - for example on each side of a river. Just like all parts of the process, the planning phase is of course complicated by the fact that inverted siphons are situated under water.

Before we commence installation of an Aarsleff CIPP Lining we always carry out inspection and cleaning processes. Sometime we have to send divers into the siphons to carry out CCTV inspections. Cleaning is often carried out by pulling special a cleaning tool through the siphons – from one side over a river to the other.

We carry out most of our inverted siphon renewal projects using a twin lining system. First, we install a preliner impregnated with a special type of resin. Afterwards, we typically install, or rather push, the main Aarsleff CIPP Lining inside the preliner by means of water pressure. The main lining is also impregnated with resin. When both preliner and main lining are in place we use heated water to cure the resin.

The effectiveness of our technology and methods have been proven time and again to be ideal for renewing live flooded siphons, and therefore it comes as no surprise for us that we experience an increased demand for our experience and skills.