Horizontal Directional Drilling (HDD)

We Use HDD to replace difficult water lines, repair work to complete replacement. Examples would be a long water line that runs under a neighbors property and they do not want the landscape trenched or a water main that runs under a driveway or patio. Directional drilling can also go under retaining walls and come up near or under a foundation. In Seattle sometimes the water main will be very close to a fence or even not be infront of the home because you are on a side street and your water meter is at the end of the block these are when having a directional drill can make the job possible and affordable.

We also use the HDD method for gas and electrical conduits. Sewer lines where there has never been one are another task that we can do. Some sewer lines have dips or bellies and pipe bursting or lining would only clone the bad spot in the line, we can use the Directional Boring method to create another line right next to the old sewer and the job will still be a trenchless installation.

Seattle has old galvanized water lines that fail or need replacement where Bothell or Kenmore usually have black Poly lines from the 80's that are failing. A different approach is used for each area. So A Seattle home is usually limited in space a Kenmore or Bothell home has usually lots of space to work in Galvanized pipe usually can not be repaired but a black poly pipe has a chance at being spliced. But a lot of times the poly will just get a hole in a different spot a short time later..

Houses that have water intrusion in the crawl space or basement can have clogged footing drains or perhaps even no footing drains at all and the cost for excavation is so high that it is prohibitive to do. This is where directional boring can install perferated pipe to drain the water away. Though not as good as a complete drain system with foundation coating and gravel installed it may be enough to reduce the water intrusion by providing a easy path for the water away from the home. Every job is different but by having HDD in our arsenal of tools we can win the battle.

The definition or Process description.

Horizontal directional drilling (HDD) is a steerable trenchless method of installing underground pipes, conduits and cables in a shallow arc along a prescribed bore path by using a surface launched drilling rig, with minimal impact on the surrounding area. Horizontal directional drilling is the most commonly used trenchless process for installing water pipe and is suitable for a variety of soil conditions and jobs including installation of pipe crossing waterways, roadways, congested areas, environmentally sensitive areas, and areas where other methods are costlier. Unlike other techniques, horizontal directional drilling provides less traffic disruption, lower cost, deeper and/or longer installation, no access pit, shorter completion times, directional capabilities, and environmental safety.

Horizontal directional drilling requires a specialized boring machine to create a horizontal shaft and subsequently pulls the new pipe into and through the opening with the aid of drilling fluid. Horizontal directional drilling involves three essential steps. First a pilot bore is created, covering the distance over which the pipe is to be installed. Highly sophisticated electronics enable the drilling rods to be carefully guided and its direction of travel to be monitored. Reamers are then pulled back to obtain a diameter large enough to accommodate the diameter of the pipe. Simultaneously, drilling mud is pumped into the bore to stabilize the boring and to prevent soil collapse. In the final step of horizontal directional drilling, the new pipe to be installed is pulled back through the bore. Horizontal directional drilling provides the option of completely replacing old pipelines in a new location as an option to rehabilitating an existing pipe.

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