Why your next construction project might require directional drilling

Underground infrastructure plays such an important role in New Zealand's civil construction and infrastructure industry, and directional drilling provides an alternative by allowing contractors to install underground services along a planned route with minimal excavation at the surface.

The biggest benefit to directional drilling: it facilitates repairs, maintenance, or the installation and upgrade of new services around existing roads, buildings and utilities, which can make traditional trenching difficult or disruptive.

We talk about the benefits of underground directional drilling on your next infrastructure, development or services project.

1. Installing underground utilities and services

Utility installation is one of the most common applications for directional drilling, and for good reason. In tightly-packed new developments underground connections for water, telecommunications, electricity and other essential services can often be hard to achieve through traditional trenching, whereas directional drilling allows contractors to install these services without excavating a continuous trench along the entire route.

Excavating across a busy road requires traffic management and creates delays for road users, whereas directional drilling can reduce the extent of surface excavation, helping contractors limit disruption during installation.

The method also supports infrastructure upgrades in developed areas where existing underground services leave limited space for new connections. Contractors must still locate buried assets accurately and establish suitable clearances before drilling begins.

To keep things running smoothly and mitigate the risk of drilling into pre-existing structures or utilities, the contractor must consider the required bore diameter, installation depth and distance between entry and exit points. Planning these details early helps determine whether directional drilling is suitable for the project.

2. Crossing roads, waterways and other obstacles

Infrastructure projects frequently require underground services to cross physical obstacles like railway corridors, waterways and established landscaping can make conventional excavation challenging, particularly when surface disruption must be kept to a minimum.

Waterway crossings can benefit from this approach. However, these projects require careful consideration of ground stability, groundwater conditions and environmental requirements. Your contractor must assess the proposed route and manage drilling fluids to reduce the risk of unintended returns or contamination.

Railway crossings are also likely to require additional approvals, engineering requirements and restrictions on construction activities, and your contractor should consult the relevant asset owners early to establish the conditions for working beneath their infrastructure.

Although directional drilling can simplify certain crossings, it isn’t always the best method for every site or project.

Choosing the right application for directional drilling

Project teams should assess the proposed alignment alongside the wider construction programme. The location of entry and exit points, equipment access and the availability of accurate utility information can all influence the installation method. Coordinating these requirements early helps reduce avoidable delays and allows other construction activities to proceed more efficiently.

Directional drilling contractors can contribute during the planning stage by reviewing site constraints and advising on the feasibility of the proposed route.

Directional drilling offers practical advantages for utility installation, obstacle crossings and development projects where conventional excavation may cause significant disruption. Its suitability depends on the ground conditions, installation requirements and constraints surrounding the proposed route.

Before committing to a method, project owners should investigate underground services and confirm any environmental or asset-owner requirements. An experienced directional drilling contractor can help evaluate these factors and establish a suitable construction approach.

Early planning gives project teams a clearer understanding of the work involved, supporting safer installations and more predictable project delivery.