All Terrain Technology Confidently Bores Path for Power Cable Underground

NPL Construction Company turns to Ditch Witch All Terrain drill to complete difficult river crossing other HDD equipment could not.

The horizontal directional drilling (HDD) equipment available and the skill levels of experienced HDD crews make many of today’s HDD drilling installations seem “routine.”

While no two drilling jobs are the same, a high percentage of current HDD installations are initiated with a reasonable assurance that they will be successfully completed. But this is not always the case. There are difficult, challenging jobs in conditions that put the end result in question.

Utility contractor NPL Construction Company recently completed a challenging project when working to cross the Blue Earth River about 10 miles south of Mankato, Minnesota.

“The job was to install duct under the river to replace aerial electric cable,” said Mike Theis, NPL superintendent. “The project owner was Benco Electric. The overhead cable along the river was the only part of the system in the area that was not underground. Benco had been planning to take the power cable underground for several years, and we got involved after three failed attempts made by another contractor using rented equipment.”

Both surface and subsurface conditions on the job site posed challenges for operators, described Theis. The launch point was 75 feet above the river. The job then required operators to proceed 22 feet below the river bottom, cross the river and come up 188 feet to the exit point on an eroded hillside. The soils contained sand, sandstone, limestone and cobble.

“Two of the unsuccessful attempts using equipment by another contractor were made with a 36,000-pound pullback machine, and with a larger 60,000-pound pullback model,”Theis said. “Representatives of the rented equipment’s manufacturer were on site to assist with the project. On every shot, they were unable to track the bore to the exit point and had to abandon each attempt.”

NPL was asked to try what others couldn’t accomplish, and brought in a Ditch Witch® JT60 All Terrain (AT) drill unit and support equipment to get the job done with confidence.

“NPL does joint trench work with Benco,” added Theis. “We’ve done a lot of river crossings in southern Minnesota. We are known for having experience in this type of work.”

The pilot bore under the river was completed on the first attempt, but the four-inch poly duct got stuck during pullback. A second pilot hole was made without incident, and this time pullback was completed. The bore length of the finished job was 1,220 feet. “We could not have done this job without the AT machine,” said Theis.

Ditch Witch AT models are equipped with a dual-pipe, mechanical drilling system that enables them to drill and be steered effectively in rock and other hard conditions impossible for a machine with conventional equipment of comparable size. An inner rod drives a rock bit, and the outer pipe steers the downhole tool while drilling the pilot holes and providing rotary torque for the hole opener during backreaming.

The JT60 AT (60,000 pounds of pullback) utilized a 6 ½-inch bit on the pilot bore and a 8 ½-inch hole opener on the pre-ream.

A Subsite® Electronics TKQ tracking system with a locating range to depths of 110 feet, and tracker with drill-rig range to 2,000 feet was used to guide the bore. The shallow, 4 ½-foot depth of the river allowed the tracking receiver operator in waders to walk the length of the bore. The signal remained strong throughout the crossing, Theis described.

Another factor contributing to the success of the project was recycling drilling fluid. “It was imperative to avoid inadvertent returns that would release drilling fluids into the river,” Theis said. “The AT drill units use about the same amount of fluid as a conventional machine and enabled us to drill through rock and avoid using a mud motor, which was unacceptable for this job. In addition, we recycled drilling fluids, which reduced the amount of fluids on-site and brought us significant savings in total costs.”

Until recently, recycling was limited to installations made by large drilling units of 100,000 pounds pullback and above. However, the introduction of compact recycling systems enables recycling with smaller, midsize HDD equipment.

NPL used a trailer-mounted Ditch Witch MR90 recycling system designed specifically for drill units with pullback ratings from 20,000 to 60,000 pounds. It is a self-contained, drilling-fluid mixing and recycling system and is the only unit in its class with an integrated rear spoil hopper with mixer for drying additives.

“We estimate that recycling saved about 75 percent in fluid costs by reducing the amount of water needed, saving on fluid additives, and reducing hauling costs to bring in water and dispose of fluid,” Theis said.

An added benefit of the MR90 is that it can be transported when supply and spoil tanks are full.

“We completed the installation in two weeks, start to finish,” Theis said. “Benco personnel ran cable through the duct and connected it to their system at each end.”

Benco Electric is a Touchstone Energy partner and provides electricity for 18,000 co-op members in Minnesota. The association was established in 1936.

Based in Phoenix, Arizona, NPL is a national utility contractor which installs and replaces more than 10 million feet of pipe and cable each year employing a variety of construction technologies. The Blue Earth River project was done by the company’s Upper Midwest division.

The Ditch Witch product line includes HDD equipment, drill pipe, downhole tools and performance parts; fluid recyclers; trenchers; vibratory plows; vacuum excavators; mini skid-steer loaders and other utility equipment; and support accessories and equipment. Ditch Witch products are sold and serviced by the worldwide Ditch Witch dealer organization. Ditch Witch is a Charles Machine Works company.

HYDRAULIC BREAKER
Used for construction and demolition, our breakers can be used to break up asphalt, concrete or even clay. The hydraulic hammer is perfect for any small or medium job you might have. More up-time in the field is always the goal, and with only two moving parts and a few seals, there’s no reason for down-time.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

ROCK SAW

Best suited for irrigation and fiber installation, the Rock Saw attachment can effortlessly cut through rock, concrete, and other tough materials with unmatched precision. 

Compatible Models

SK1050, SK1550, SK1750

BACKHOE
Easily move materials for rebuilds, new construction, footings, utility repairs and more with this compact and versatile attachment.
Compatible Models

SK800, SK900, SK1050, SK1550, SK1750

STUMP GRINDERS
Featuring a heavy-duty boom design, powerful stump grinding attachments quickly shred stumps down to nothing. Easy maneuvering from stump to stump and increased visibility turns more ground stumps into more profit.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750, SK3000

MULTITASK TOOL
Your multipurpose tool for the ultimate multi-tasker is here. Engineered to grab tight to heavy materials and move them with ease and precision, the multi-task tool is your go-to for heavy applications. Easy to operate with convenient, functional levers.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

CORE DRILL
With the MC-450 coring attachment, utility maintenance is simple and less disruptive. Featuring intuitive controls and an integrated water tank, the MC-450 is the perfect choice for quick cuts and a more productive coring process. A fully adjustable 0 to 280 rpm speed allows for enhanced control and greater productivity.
Compatible Models

SK1050, SK1550, SK1750

SOIL CULTIVATOR
Prepare food plots, gardens, and landscaping projects with a soil cultivator. It gets land ready by stirring organic material back in the soil for a healthier, more stable lawn. Buries the biggest of rocks for a looser topsoil.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

BLADES
Whether you’re looking to increase dump height or digging depth, attaching a backfill blade is an easy way to save manpower on your jobsite while working with precision and timeliness. Available in various widths.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

AUGER DRIVER
Ideal for landscaping and tree care, an auger attachment will expedite hole creation and allow operators to quickly plant trees or install fence posts than if they were hand-digging or relying on a hand-held auger. Available in 6" to 30" diameters.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

TILLER
Tough and effective tillers prepare your garden by breaking up tough soil and removing unwanted weeds. Available in 4' width.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

GRAPPLES
Tree grapples come with 48" or 57" openings to efficiently remove logs and debris from the jobsite. It has an excavator style boom design with a powder coat finish and a cylinder lock for increased safety. Brush grapples available with a gap opening of 29" and widths of 42" or 54".
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

CARRY ALL LEVELER
One of our most simple yet versatile attachments, the Carry-All Leveler is perfect for carrying bulky material, leveling soil and adding a flat, smooth finish to your project. Available in 49" width.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

BUCKETS

From landscaping and hardscapes to tree care and construction-grade tasks, your stand-on skid steer can take on more than you think. We've got you covered with a variety of buckets from 4-in-1 to heavy and light material buckets. Widths range from 34" to 66".

Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750, SK3000

PALLET FORKS
Take on your heaviest loads with precision and dependability with Ditch Witch pallet forks. They easily attach to any of our skid steers and can easily accessorize with hay spikes, brick guards, and much more to add even more ROI. Available in widths ranging from 36-48.75" and lengths from 36-48".
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750, SK3000

MICROTRENCHER
Fiber installation and other street-located work is rapidly growing. A microtrenching attachment is key for operators looking to get into fiber installation at the street level. They cut both concrete and asphalt in controlled increments so contractors don't need to stop traffic. Maximum width options are 0.5-1.5” or 2” with maximum depths of 12” or 16”.
Compatible Models

SK1050, SK1550, SK1750, SK3000

ROTO WITCH®
The Ditch Witch Roto Witch® attachment is used for short bores underneath sidewalks, driveways and other obstacles. It offers great digging performance while minimizing jobsite restoration. Compatible with numerous Ditch Witch stand-on skid steers, the Roto Witch attachment can bore and backream up to 12" (300 mm) in diameter.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

PLOW
Install fiber and other utilities quickly with a vibratory plow attachment for your skid steer. It creates less ground disruption and cleanup than traditional trenching to get the job done faster. Available in maximum depths of 14" and 24".
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750, SK3000

POWER RAKE
Clean, level and prep jobsites or smooth and loosen soil for sodding with a rake attachment. Most rake attachments require 10 to 14 gpm, but the higher horsepower creates even more drum torque to tear through the most demanding soil types. Width measures 4'.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

MICROTRENCHERS
Fiber installation and other street-located work is rapidly growing. A microtrenching attachment is key for operators looking to get into fiber installation at the street level. They cut both concrete and asphalt in controlled increments so contractors don't need to stop traffic. Maximum width options are 0.5-1.5” or 2” with maximum depths of 12” or 16”.
Compatible Models

SK1050, SK1550, SK1750, SK3000

ROTO WITCH®
The Ditch Witch Roto Witch® attachment is used for short bores underneath sidewalks, driveways and other obstacles. It offers great digging performance while minimizing jobsite restoration. Compatible with numerous Ditch Witch stand-on skid steers, the Roto Witch attachment can bore and backream up to 12" (300 mm) in diameter.
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750

PLOWS
Install fiber and other utilities quickly with a vibratory plow attachment for your skid steer. It creates less ground disruption and cleanup than traditional trenching to get the job done faster. Available in maximum depths of 14" and 24".
Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750, SK3000

TRENCHER

Stay efficient on large jobsites with a trencher attachment for your skid steer. It’s a smart alternative to large, specialized equipment for utility installation and landscaping jobs. Available in standard 6”, 8” and 12” maximum widths with maximum depths of 36", 38", 48” and 55.5”.

Compatible Models

SK600, SK800, SK900, SK1050, SK1550, SK1750, SK3000