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Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

MAILING ADDRESS: 1120 SW 5th Ave, Room 1000, Portland, OR 97204

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Jack and Bore

Jack and bore is a method of horizontal boring sewer construction. Construction crews drill a hole underground horizontally between two points without disturbing the surface between sending and receiving pits. The tool works in a way very similar to a jack hammer and uses air to pound its way through the ground. These are the basic steps of jack and bore construction:

  • Boring machine in pitDig sending and receiving pits to the required depth.
  • Shore the walls if needed.
  • Lay a boring machine in the pit.
  • Set up tracks and insert an auger in a casing.
  • The boring machine pushes the auger and casing through the ground simultaneously while the machine turns a cutting head through the ground.
  • The auger carries the debris back to the machine in the pit.
  • Dirt and debris are shoveled out of the pit.

What to Expect During Jack and Bore

  • The equipment is loud and causes vibration that you may feel in your home or business. This is standard for this method of construction.
  • Both preparation and post-jack and bore work can take a few weeks to complete.
  • There may be road closures and lane restrictions.
  • Inserting pipeThere may be inactivity between some phases of this process.
  • Typical work hours are 7:00 a.m. to 6:00 p.m. Monday through Friday, but the contractor may schedule work during the same hours on Saturdays.