Work is continuing on the Hinahina Bridge project in the Catlins.
Clutha District Council contractors have begun demolishing the 140m bridge structure, which spans the Catlins River about 4km from Owaka.
A council representative said this would take about a month.
During demolition, sections of the bridge will be brought down in manageable pieces and winched to shore, within the footprint of the bridge.
Once the bridge has been demolished, stages seven and eight of the planned rebuilding can proceed, which involve setting up a launching beam and gantry operation to lift the first of the new bridge’s core beams into position.
Contractors will then repeat the operation on each consecutive gantry until the bridge is complete.
During these operations small vessels using the waterway might need to stop until it is safe to proceed.
Due to the nature of demolition projects, precise time-frames could not be provided for work to be completed, although the council expected the critical works to take a month.
Authorities and the Owaka Yacht Club had been notified of activities, and warning signs had been installed at the Owaka boat ramp.