Drinking water pipeline for Gothenburg permanently protected

In Gothenburg, a new drinking water pipeline was installed in contaminated soil under the Göta älv river using the HDD method. For safety reasons, the client requested an inspection of the pipeline both before and after installation. This task was successfully completed using the Barrier Pipe SLA^® system.

The island of Hisingen, Sweden’s fifth-largest island, is home to the majority of the Port of Gothenburg as well as several oil refineries. For the construction of a new water supply line from the center of Gothenburg to the island of Hisingen, the Göta älv river had to be crossed over a length of approx. 560 m. The HDD drilling was carried out by the company BAB Rörtryckning AB. Due to the geological conditions with contaminated soil and drilling at a depth of more than 30 m, the crossing of the Göta älv river was highly complex.

Therefore, the Barrier Pipe SLA^® system in the dimension 630 x 70.3 mm SDR 9 was used. The Barrier Pipe SLA^® system reliably prevents the permeation of pollutants. The metallic permeation barrier enables permanent protection of sensitive media and the environment. In addition, the electrical properties also offer the possibility of locating the pipeline and testing for integrity before and after installation. The core pipe and barrier layer are reliably protected by an additive protective layer, making the system suitable for trenchless installation.

The pipe connection was carried out using the heated tool butt welding process. The pipe string to be pulled in was tested for integrity using a breakdown test with a high-voltage testing device. The installation of the pipe string only began after a positive test result. After the horizontal directional drilling process was completed smoothly, the pipe string was tested again: the integrity of the pipeline was also confirmed after installation and accepted by the construction management. The pressure pipe and permeation barrier are intact.