Progress on Pahurehure Inlet Bridge
Work is continuing at pace on the new replacement causeway bridge spanning the Pahurehure Inlet, but motorists might never notice the extensive work going on under their wheels as traffic flows are maintained throughout.
The original bridge, built in the 1960s, was only 11 metres long and was made up of two two-lane bridges. But modern motorway use, updated earthquake standards and the greater load of two extra lanes to widen the motorway meant that the bridge needed to be redesigned and completely reconstructed.
Construction began in 2017 with the addition of two 60-tonne beams next to the existing Southbound bridge. These allowed the diversion of all motorway traffic on to the Southbound bridge.
The old Northbound bridge was demolished in 2018 and replaced with a single 30-metre span across the inlet, sitting one metre higher than the previous bridge. Both directions of traffic were diverted onto the newly constructed half of the bridge in November 2018.
Extensive work has been undertaken in the first quarter of 2019 to protect the sensitive coastal marine environment during the demolition of the old northbound bridge and in preparation for the final construction stage.
This widening has enabled an improvement to tidal flow under the bridge using retaining walls and revetment (coastal edge protection) rock from locally-quarried basalt.
The revetment provides habitat for the diverse marine life thriving in the inlet as well as protecting the shore line from coastal erosion. A family of ducks, two shags and a heron have made their home in the surrounds and often visit the work site or fish nearby.