In February 2023, Brownline was involved in two parallel HDDs in the Westland region. Installing a heat grid required crossing under greenhouses in an S-curve.
These parallel drillings were carried out by Heijmans and are part of the local heat grid project “Warmtesysteem Westland”. This project involves drilling for geothermal heat sources and connecting them to the local horticultural greenhouses. These greenhouses consume a lot of heat to grow their fruit, vegetables and flowers. A local source for this heat is important to increase the sustainability of the world-renowned Westland greenhouse industry.
S-curve under the foundation
To complete the network, two HDD crossings (for a supply line and a discharge line) were completed underneath a greenhouse complex, about 12 m / 40 ft below the foundation piles. With a few meters in between, the two pipelines were installed with an S-curve design. The drilling curved 31° right before curving 54° back left, with a combined radius of 270 m / 886 ft. At the other side of the greenhouse, the drill punched out after 520 m / 1706 ft.
Highly accurate underground localization was needed in order to carry out these crossings as planned. Using the Drillguide Gyro Steering Tool, the drill head’s exact position could be tracked during drilling. As a result, the pipelines were installed exactly as planned. The GST is not influenced by external interference and also does not require surface access. These benefits make it the perfect tool for these kinds of crossings.