Transmission Gully may open late on 2016 delays

The joint venture building the $850 million Transmission Gully motorway north of Wellington warned the 2016 earthquake followed by torrential rain may delay the road opening, although it made good time in the typically problematic winter months.

The project is working to an April 2020 deadline to open the 27-kilometre, four-lane highway in a complex construction programme, although in heavily redacted documents released under the Official Information Act, project director Boyd Knights of the CPB HEB joint venture said the programme had been updated to include the delay and remediation works from the November 2016 earthquake and flooding.

"Notices for time impacts from the seismic and flood events have been submitted and are under review from NZTA/WGP (Wellington Gateway Partnership)," Knights said. "The contract planned service commencement date remains April 2020; however if the full unapproved time impacts from delay events included then forecast at 6 August 2020."

The public-private partnership contract between the New Zealand Transport Agency and WGP contains provisions for the contractor to seek relief from the government agency if certain events beyond its control would see it fail in its obligations. NZTA and the CPB HEB joint venture didn't respond to questions about the status of the notices.

Earlier this year, the JV acknowledged the delays caused by the quake and flooding but said it managed to catch up on lost time last summer and has publicly stuck to its 2020 opening target. In NZTA's 2017 annual report, the government agency said good progress was made on Transmission Gully with completion expected in mid-2020.

"Over the course of the project, there has been constant dialogue between the Transport Agency, Wellington Gateway Partnership and the joint venture, which has included a number of technical and commercial matters that may result in dispute between the parties," NZTA's report said. "The Transport Agency does not consider that any matters raised to date are likely to materially impact on the timing of delivery of the project or on the Transport Agency's costs of the project, but it will continue to closely monitor the project and the risks associated with it."

That took a knock earlier this year when the joint venture found work to dispose of "unsuitable material, ground improvements, environmental controls, topsoils stripping and stockpiling" didn't appear to be "sufficiently allowed for in the consents". Greater Wellington Regional Council then outed the consented shortfall to be about 50 percent, although the joint venture later disputed that saying its tender proposed a higher level of earthworks and that it now has consents covering the hole and giving it extra breathing room.

The construction partners went on a hiring binge earlier this year to meet that extra work, at a time when the sector contends with skills shortages against the backdrop of a major pipeline of residential, commercial and infrastructure work.

The JV's regular monthly reports from May to September this year show a variety of challenges emerging, from the discovery of a 19th-century cannonball shutting down work, the first lost-time injury when a worker suffered a fracture exiting his dozer, to earthworks cuts needing more drying than anticipated.

Still, the construction effort managed to shift 670,000 cubic metres of earthworks through winter, including 196,000 cubic metres in July when it had only planned to move 40,000 cubic metres.

The reports note "good productivities" were achieved in May and June, and while rain in July caused some setbacks, wet weather in August and September didn't create too many problems. A further 231,000 cubic metres was shifted in September, with the report noting "good progress" being made in the earthworks.

The joint venture managed to overcome issues with landscaping and was in the final stages of clearing consents and ensuring they met management plans after issued for construction drawings were inconsistent with the approved plans during the winter months.

(BusinessDesk)