Transport for NSW (TfNSW) has released new footage of the controlled blasting on the Coffs Harbour bypass project as construction of three tunnels moves into full swing.
TfNSW regional director north, Anna Zycki, said that following the successful completion of work to prepare for the start of tunnelling, major tunnel construction work is underway.
“This is an exciting milestone for the project and the people of Coffs Harbour,” Zycki said.
“We know from the earliest discussions with the community how important tunnels are for Coffs Harbour residents, so it is very pleasing to see major work start on this aspect of the project.”
Most other road tunnels under construction across the state are being built with the use of tunnel boring machines, but because of the hard rock in the hills along the bypass alignment, these tunnels will be created through controlled blasting.
Zycki said tunnel construction has started at Gatelys Road, where significant work had been done to get the site ready.
“There has been a lot of anticipation about work starting on the tunnels and now we can really get moving,” Zycki said.
Before controlled blasting of the tunnels started, the site was set up to include compound offices, water treatment plants, material laydown areas and parking for plant and workforce vehicles.
Then the top exterior of the tunnel portals was stabilised with bolts and shotcrete, and the entrance to the tunnel portals was excavated using controlled blasting, bulldozers and excavators.
The three tunnels will each contain a northbound and southbound ‘tube’, making six ‘tubes’ in total, which will be built in stages.
The longest, and where work started first, is the 410-metre Gatelys Road Tunnel. The Shephards Lane Tunnel will be about 320 metres long and the Roberts Hill Tunnel about 160 metres.
The tunnels will also include cross passages which are used in emergencies to provide a safe exit for road users if there is a blockage, fire or similar situation that requires motorists to evacuate.
Truck parking bays and height detection monitors will be placed before the entry to each tunnel. The vehicle clearance height in the tunnels will be 5.3 metres.
The $2.2 billion bypass is expected to be open to traffic from late 2026 and fully completed in late 2027.
Quick facts
Earthworks: 1.3 million cubic metres moved to date
Plant: about 600 pieces of plant mobilised
Bridges: Eight of 17 bridges under construction
Bridge piles: 108 of 272 bridge piles in place
Concrete: 6019 cubic metres used to date