Survey Group controlled and monitored a TBM for a 2m diameter bore shaft from Water Street to Nikau Street in Mt Eden as part of the C6 CRL section, diverting a major existing stormwater line from the two new CRL tunnels.

The complexity of the work required surveying down a 15m deep x 8m wide shaft, with the tunnel alignment geometry a very small radii for tunnel boring.

“TBM’s do not turn easily, and with the target 500m long and 20m deep following an S bend, to hit a bullseye within 30mm accuracy was a great achievement and much appreciated by the client.”

Our Role

  • TBM Survey and Control
  • As Built Tunnel Surveys
  • Construction Monitoring
  • Digital Engineering
Our Projects: City Rail Link