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The dos and don’ts of horizontal directional drilling On HDD projects, particularly for larger and more complex ones, there are some things you do want to see and some you don’t. HDD is not as simple as it appears. Maxibor outlines what to look for. Maxibor is a leading horizontal directional drilling company in Australia. Photo by Maxibor
HORIZONTAL DIRECTIONAL DRILLING (HDD) is the design and installation of underground pipelines to serve as conduits for water, sewer, electricity, gas, fuel and oil, telecommunications and hydrogen. The technology makes it possible for drillers to direct their drilling equipment horizontally to create pathways through a wide variety of terrain ranging from alluvial sands, gravel and cobble to fractured or very hard rock. The innovative design of bore pathways can solve many complex project challenges. Challenges including environmental, traffic, geological and underground utility congestion can be overcome. There are various smarts in your approach to an HDD project. Outlined below are some dos and don’ts. Dos – before drilling 1. Getting the design right is paramount. The borehole needs to be constructible. It would help
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if you looked for HDD designers who are experienced in delivering projects. Technical design knowledge is important, but it is even better with understanding the equipment to be used and practical in-field involvement in delivering difficult HDD projects. 2. HDD designer with experience. Engaging those with experience on more challenging and innovative HDD projects facilitates the exploration of solutions beyond the conservative traditional shorter and smaller diameter bores. Designers with experience add significant value by examining alternative HDD solutions. 3. Geological investigation. It needs to be sufficiently representative of the designed borehole alignment. The geological conditions drive the Rate of Penetration (ROP) and equipment required, which drives the time, cost, and price for the HDD works. If there is doubt that the geological information is
INSIDE WATER September/October 2022
insufficient, the additional cost to achieve more certainty is a good investment for all stakeholders. 4. Visit the site. Site visits and interaction with the asset owner are vital to designing and delivering the best HDD solutions. Informed design and delivery solutions can be explored when people are face to face at the site. 5. HDD designer and installer relationship. Where there is a close relationship between the HDD designer and installer, they develop a productive and costeffective design, construction methodology and a realistic construction schedule. It will optimise delivery outcomes for all stakeholders. Integrated design and construction HDD providers like Maxibor will achieve the best client outcomes. 6. HDD equipment. Engaging an HDD delivery provider with fitfor-purpose HDD equipment to deliver the project is essential. On larger and remote projects, having equipment in good working order and spares is critical to projects running to schedule. An HDD provider with an expansive fleet of equipment allows for more adaptability in overcoming uncertainties. 7. Other HDD resources. Engaging an HDD delivery provider with sufficient resources ensures that project management, drilling operations and HSEQ are all maintained and managed to good practice standards. Insurance coverage and financial capacity are among the other important factors to consider. 8. Cooperation and knowledge sharing. HDD design and delivery providers that cooperate and share add more value to your business. They increase the potential for optimised project