Case Studies

See what superior HDD tooling looks like in action.

With 70+ years of experience in the commercial drilling industry, we’ve pretty much seen it all. Our case studies outline specific challenges drillers have run into and how our signature red tools have achieved new industry breakthroughs for the toughest, most complicated jobs.

  • Hoquiam River Sewer and Water Line Replacement
    Sewer line was old, leaking and needed replacing. An adjacent deteriorating water line was also replaced. The soil consisted of soft clay with wood in the soil.

    Project Background

    When the city of Hoquiam, WA identified a leak on a sewer force main that pumps raw sewage across the Hoquiam River they immediately notified local residents and declared the repair as an Emergency Project. Department of Ecology and Fish and Wildlife officials were notified. City crews and local contractors completed the work in June 2016.

    Downing Diversified Directional Drilling was awarded the bid as the HDD subcontractor with Rognlin’s Inc. out of Aberdeen, WA as the prime. The decision was made to make two 700 to 800 foot bores; one for a new sewer line then move upriver approximately 200 feet to install a new water line, replacing an existing line that lay on the surface of the river bottom. The new water line was to be placed at a depth approximately 20 feet below the river bottom to protect it.

    Soil Conditions

    The soil conditions consisted of soft clay with wood and the bores had to go down 60 feet from the bank to get the required 20-foot depth below the bottom of channel. Potential problems included a frac-out in a sensitive environment and collapse of the hole during the pilot bore.

    • Clay Clay

    Solution & Products Used

    Downing piloted the bores using a TKQ Subsite locator and a deep sonde beacon walk-over locating system. A Melfred Borzall Steep Taper Ultra Bit with an MB ELH series 100 gpm flow transmitter housing in line were used for the pilot bore. Once the pilot hole was completed, a Melfred Borzall 20-inch Terminator reamer and 18-inch packing Barrel Stabilizer were attached to complete the back-ream. Due to the soft ground conditions the transmitter housing was left in line during each of the pull backs to make sure the reamer and product were tracking correctly in the pilot holes, and both bores were successfully completed without any frac-outs or holes collapsing. The old lines were replaced with 12-inch DR18 Fusible C-900® PVC pipe product from Underground Solution. The job was completed in five days.

Featured Product

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Fast Back
We Just Sped Up the Speed of LightA small, mud-filled pit is the last place you want to remove the drill head and install a reamer. And now you don’t have to with the FastBack® family of pullback devices from Melfred Borzall. FastBack devices allow you to pull back product without ever taking off the drill head, so within minutes of completing the pilot bore you’ll already be pulling pipes back. Fast and easy underground production that puts you ahead of the curve. . . that’s the Borzall Edge.



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