In June 2023, Brownline contributed to the completion of two parallel crossings in Rijswijk. To install heat pipelines, HDD was used to cross motorway A4 along with many other obstacles.
These HDD crossings were carried out by contractor A.Hak, commissioned by Gasunie, as part of the WarmtelinQ project. This project consists of pipelines to transport residual heat from the Rotterdam harbor to the The Hague area. It will then be used to heat residential and office buildings, but also greenhouse complexes. Using directional drilling, the pipelines were installed under motorway A4 in Rijswijk.
Various obstacles to cross
In addition to the A4, there were more obstacles for the drill to cross. On both sides of the motorway were sheet piles that needed to be crossed. Next to the motorway, there was also a viaduct for cyclists with foundation piles above the drilled line.
After the motorway, the drill crossed tram tracks and an archeological site, where objects from the Roman era were found in 2014. To safely cross under all these obstacles, the two bores were almost a kilometer long and 33 m / 108 ft deep.
GPS track & Pressure-While-Drilling
To ensure that the drillings would return to the surface at the exact planned spot, extra verifications were carried out using our GPS track add-on. This allowed for a perfectly accurate punch-out. Pressure-While-Drilling (PWD) was also used on this project. PWD allows the downhole pressures to be constantly monitored while drilling, which helps to achieve a safe HDD crossing without inadvertent returns.
The steel pipeline had to be laid out in a busy urban environment. During pullback, traffic could drive underneath the pipe. A.Hak made a video about this pullback operation. Drone footage shows the pipe laid out through the city and pulled in above an intersection. Watch this video using the link below: