Wet and windy weather, together with unforeseen ground conditions have moved the completion date for construction of a new half-bridge and safety barrier on the Rimutaka Hill Road into the first weekend in November, later than originally planned.
NZTA Regional Transport System Manager Mark Owen says excavation of the hillside identified that bedrock was deeper than expected and therefore the the new half bridge has had to be modified to suit the ground conditions.
“The half bridge has to sit on bedrock, not the loosely compacted material that the crews have been excavating.
“We’ve had to modify the design to accommodate the deeper foundations, adding extra time to the construction programme.”
Severe wind and wet weather at the end of September also delayed work, with the Rimutaka Hill Road being closed on two separate occasions in one week. Throughout both projects, work will have to be deferred if rain, high wind gusts or snow occur on the Hill.
“The biggest thing for us is getting the job done safely and minimise the impact on motorists and the trucking industry needing to travel over the Hill,” Mr Owens says.
“We’ve made a commitment to freight operators to provide a two week window between the end of the half bridge project and the start of the corner easing project, when the road will be fully open in both directions, allowing the movement of houses and other over dimension loads. We intend to honour that commitment, albeit the start of the two week window will be slightly later than originally planned.”
NZ Heavy Haulage Association Chief Executive Jonathan Bhana-Thomson said while the project had impacted on freight operators, the close collaboration between the project team and freight was appreciated. “The work has to be done but the inconvenience and disruption has been managed by scheduling this two week window and by keeping us actively informed of work progress.”
The corner easing project is now scheduled to start late November. “Our plan is to complete the major earthworks before Christmas,” Mr Owen says. “This is the major construction work with the same traffic restrictions as the half bridge project, for a shorter period as rock is removed from the hillside. We can finish off the resurfacing and drainage work which will have less impact on people’s journeys in terms of traffic restrictions in the new year.”
For more information about the Rimutaka Hill Road improvements visit https://nzta.govt.nz/rimutaka (external link) .