Twin barrel DN1500 microtunnelling for Delaney Civil, delivered for Hilltops Council
Quick facts
- Head contractor: Delaney Civil
- Principal: Hilltops Council (TfNSW specifications apply)
- Designer: Stantec
- Location: Boorowa Street roundabout, Young NSW
- Duration: 21 April – 15 July 2026
- Method: Laser guided microtunnelling with a microtunnel boring machine (MTBM)
- Scope: 2 twin barrel bores, approx. 172.5 m total
- Pipe size: DN1500 Humes J Series reinforced concrete jacking pipe (AS 4058)
The project
URBA delivered the trenchless crossings for Hilltops Council’s Young Trunk Drainage project (contract RFT000034), working as subcontractor to Delaney Civil. The new stormwater trunk line passes beneath the Boorowa Street roundabout in the heart of Young’s heritage streetscape, so tunnelling kept the busy intersection open with no open trenching across the road.
Bore 1 – Twin DN1500 under Boorowa Street
Two parallel 1500 J Series jacking pipe lines, each 59.2 m long (118.4 m total), driven from a shored launch shaft beside the roundabout. The MTBM was laser guided on line and grade the whole way, and the drive ran from late April into June 2026.
Bore 2 – Twin DN1500 second crossing
Two further 1500 J Series lines of 27.03 m each (54.06 m total), completed between 1 and 15 July 2026. The machine was then recovered and loaded out, finishing URBA’s scope on 15 July.
Ground conditions
Loose sandy gravel was found in part of the alignment that the site investigations hadn’t shown. URBA worked with Delaney Civil and Council to manage it and kept the drives on line and grade.
Client testimonial
“Under Road Boring Australia Pty Ltd consistently demonstrated a high level of professionalism, workmanship, and commitment to achieving quality outcomes. The works were completed to a high standard and met the contract requirements and expectations of Hilltops Council. … I have no hesitation in recommending Under Road Boring Australia Pty Ltd and their team for future projects.”
– Matt Clarke, Project Manager, Hilltops Council
Project gallery
