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Microtunneling for Precision Gravity Lines

Microtunneling is a remotely guided tunneling method that installs pipe on exact line and grade. An operator steers the machine from a control unit on the surface while jacking pipe follows behind it. It’s built for gravity sewer and other lines where a fraction of a percent of slope matters.

How Microtunneling Works

  1. Launch shaft. A jacking frame is set in the launch shaft at the design line and grade.
  2. Remote guidance. The microtunnel boring machine (MTBM) is steered from the surface with laser guidance.
  3. Pipe jacking. Pipe sections are pushed in behind the machine as it advances.
  4. Spoil removal. Cuttings are carried out in a slurry or auger system and the face is supported throughout.

When Microtunneling Is the Right Call

  • Gravity sewer requiring precise, consistent grade
  • High groundwater and soft soils common on the Gulf Coast
  • Deep crossings under highways, rail, and waterways
  • Sites where settlement above the bore must be minimized

Why Owners Specify It

  • Precision. Tight line-and-grade tolerances over the full drive.
  • Safety. No crew in the tunnel; the machine is run from the surface.
  • Ground control. Face pressure limits settlement under roads and structures.

Need a gravity line on grade?

To confirm or correct

Review draft only. This box will be removed before launch. Please reply with corrections to anything on this page.

  • Do you perform microtunneling, or partner with a firm that does?
  • MTBM sizes and pipe diameters
  • Longest drive and deepest shaft completed