The steady progress of fiber projects shows no signs of stopping as communities demand high-speed connections. While large cities were responsible for early projects, communities outside the major hubs have now become areas of growth for high-speed providers. As installation ramps up in these more rural, outlying areas, contractors are challenged with broader, varying ground conditions and unique underground obstacles.
To remain productive on the evolving landscapes and tough underground conditions, contractors in the underground industry know that using the correct horizontal directional drilling (HDD) equipment is key.
As fiber projects expand into these unique environments, ground conditions have become the newest technology challenge. Today, contractors face conditions underground that can vary widely, working at times in soft soil and, at others, in hard rock. In response, HDD tooling technology has evolved to help conquer what’s found underground.
HDD Technology, Soft to Tough Soils
Growth in HDD tooling has increased the complexity of matching technology to ground conditions, which likely results in premature wear when done incorrectly. HDD tooling options often focus on whether a contractor is working in conditions from soft soils to hard rock, but tooling is impacted even when operating in different soils. Sand, for instance, is abrasive and requires tooling that helps reduce premature wear.
In soft and medium soils, contractors should work with a bit that’s able to effectively penetrate the ground, assist with steering adjustments, and mix soil with drilling fluids. A drill bit that is designed with crushed carbide, for instance, provides optimized performance and extended tool life in abrasive soil conditions. Ditch Witch bits were designed for the most effective cutting structures and mixing capabilities when matched to the correct soils.
In hard, solid ground conditions, contractors run into a set of distinct challenges when installing fiber. Drill bit cutting structures often wear down prematurely, increasing the difficulty to penetrate the soil and mix drilling fluids effectively. Choosing a drill bit that more productively cuts material out of the way will give operators a more consistent annular space to install product.
Tooling made for hard rock has been one of the more important developments in the evolution of HDD. As technology has advanced, midsize drilling equipment is designed to now effectively drill and steer in solid rock. Ditch Witch All Terrain technology gives contractors the ability to have a small footprint, if needed, but also the opportunity to perform in open, rural areas when conditions require rock technology. Even in a rural area, you still have to deal with easements, and the smaller footprint is beneficial.
All Terrain systems work by using dual-pipe technology, which provides an inner drive shaft that reaches back to the HDD unit to better transfer power. With that inner shaft, the HDD’s motor can physically control exactly how much horsepower is sent downhole to the bit. If hard rock is hit underground, All Terrain technology helps drill through it by delivering more power without any other changes like increased pressure underground.
West Pacific Drilling, for instance, is no stranger to tough jobsites with hard ground conditions. The company started out as a small utility contractor in Oregon but has since grown to working on mid- and large-sized telecommunications projects, delivering fiber to communities across the region. As their work expanded, so did the geological norm of their jobsites. New projects consisted of complex environmental conditions, such as river crossings and hard rock. Despite new challenges, however, the company’s goal of efficiency and keeping project costs down remained unchanged.
“When you’re working with a variety of geographic conditions and mixed soil types, horizontal directional drills are the only way to finish utility jobs on time,” said Loyal Kuenzi, operations manager at West Pacific Drilling. “Backbone projects outside of major city hubs consist of larger diameter installations. We are laying packages of up to 24, 2-in conduits. HDDs need to maximize power to the bit for boring out and opening up a smooth path for a larger utility.”
Navigating Challenging Terrain
On a 2017 project, Loyal and his crew deployed part of a fiber backbone. The environmental conditions were tough, and they were required to complete one part of the project between January and February. This phase included laying 900 ft of conduit in 2 ft of snow.
For this portion of the project, the power and reliability of equipment was a major concern for the crew, since the frozen, rocky ground was tough enough to quickly wear down even a diamond-infused bit. Equipment also needed to handle a steep entry point so the crew could navigate a nearby river. The operator was required to quickly drill down to 40 ft before leveling off.
To efficiently navigate the challenging conditions, the company opted to rent a Ditch Witch JT100 All Terrain directional drill from its local dealer, Ditch Witch Northwest. For West Pacific Drilling, the 100,000 lb of pullback and 12,000 ft⋅lb of torque was well suited to handle the full-bore range and the large-diameter utility package. The All Terrain, patented two-pipe drilling system also improved their ability to effectively steer and drill at the steep entry angle.
Utilizing a JT100, West Pacific Drilling was able to complete a 6 ½-in pilot bore within four days. The smooth path created by the pilot bore allowed the team ample time to use a backreamer to further expand the hole and deploy the package within their time frame.
Powering Through Hard Rock
Months later, on another portion of the backbone project, weather improved for the crew, but the conditions underground were more extreme. Nearly 80 percent of this section of the project was hard rock—harder than what they previously experienced. Fractured rock was also scattered throughout the jobsite.
Between June and July, the crew deployed 1,000-ft and 800-ft bores. To finish on time, the crew was on the jobsite 24 hours a day. A first shift would operate for 10 hours, spending the remainder of their time on maintenance and upkeep. “When the night crews arrived, they’d trust the equipment was ready to operate for the full night shift,” said Loyal.
On this portion of the backbone work, operators used a Ditch Witch JT30 All Terrain drill to tackle the bores. The All Terrain technology—designed specifically for effective steering and drilling in rocky conditions—helped the team productively install utility through the tough ground and decrease the amount of fluid flow often used in rock drilling. Less fluid volume helped reduce waste, the associated cleanup tasks, and the environmental impact. For the mud that was created, the team used a Ditch Witch FX65 vacuum excavator to safely remove fluids during the drilling process.
As an added benefit for the day crew, the JT30 drill featured a hinged main and rear hood, allowing easier access to all service points in the engine and mud pump. The day maintenance crews saved time and money due to the improved serviceability.
“The importance of minimizing maintenance and maximizing reliability can’t be stressed enough when time is tight and underground conditions are taxing the equipment,” said Loyal. “Machines that are easy to maintain are important but so is being backed up by a reliable dealer. With the Ditch Witch dealership, if we needed additional rental equipment or ran into a snag on the job, they were available and ready to help.”
With the support of Ditch Witch equipment and the Ditch Witch Northwest team, Loyal and his crew met established completion dates. The hard rock made the timeline tight, but the All Terrain technology provided West Pacific Drilling a way to efficiently navigate the challenges of a demanding jobsite.
HDD tooling technology has advanced with the challenges of fiber installation. Diverse ground conditions have been one hurdle for contractors in the industry. But with the right drill and advanced tooling, even the toughest conditions like those faced by West Pacific Drilling can be overcome—and on time.
