A look at the six-phase process behind every Underground Connections horizontal directional drilling project — from desktop study to closeout documentation.
A horizontal directional drill installs utilities along a curved underground path — entering at one pit, exiting at another, leaving everything in between untouched. But the bore itself is one act in a longer sequence: each phase below carries its own equipment, its own risks, and its own success criteria.
Every successful bore starts on paper. Our pre-construction team performs a desktop study, walks the site, reviews subsurface utility records and geotechnical data, and develops a bore plan that accounts for grade, depth, soil conditions, existing infrastructure, and surface activity. We coordinate with utility owners and right-of-way authorities before the drill ever arrives.
Before the drill turns, every existing utility on the route is identified and physically verified. We follow OSHA-compliant locating protocols, perform vacuum-excavation potholing at every critical crossing, and stake the bore path. Equipment is staged, traffic control is deployed, and a documented pre-task safety brief is held with the crew.
The pilot bore establishes the route. Our operator drives the drill head along the engineered profile, steering with a downhole transmitter while a tracker maintains real-time depth and bearing readings on the surface. Drilling fluid — a controlled bentonite mix — is circulated to stabilize the borehole and remove cuttings.
The pilot bore is enlarged to the diameter required for the product pipe. We select reamer type and pass count based on soil conditions, pipe diameter, and bore length — maintaining fluid pressures within safe limits to prevent inadvertent surface returns.
The product pipe is fused, hydro-tested, and staged ahead of pullback. With a swivel between the reamer and pipe to relieve torque, the pipe is pulled through the bore in a controlled, continuous operation. Tension and torque are monitored throughout so the pipe is installed within manufacturer specifications.
With the pipe in place, we perform any final pressure or continuity testing, restore every disturbed surface to original or better condition, and deliver complete as-built documentation — coordinates, depth profile, deviation report — to the asset owner.
