Causeway update (from December’s magazine)
Work on the $1.45 billion Western Ring Route is permanently changing the topography of Auckland’s motorway and includes a massive upgrade to the causeway that links the suburbs of west Auckland with the city.
Made up of five major interconnected projects that will provide a 47-kilometre-long motorway alternative to State Highway 1, the causeway project is really an upgrade to an existing motorway that was constructed in the 1950s.
Since then it has sunk considerably and is now prone to flooding during extremely high tides and bad weather. The upgrade will raise it by 1.5 metres for half its length and widen the existing dual three-lane motorway significantly. The new configuration will have five lanes westbound and four lanes city-bound. There will also be dedicated bus shoulder lanes, and the cycleway is also being improved.
As acting State Highway manager for Auckland and Northland Mieszko Iwaskow says, “The 4.8 kilometre-long Causeway Upgrade is vital to the improvement of the city’s roading network.
“This particular section of motorway sees more than 90,000 vehicles each day, along with the hundreds of daily users of the cycleway that runs alongside it.”
Motorists can see the transformation progress daily as huge volumes of rock are trucked in and shaped to support the new road. Causeway Alliance project manager Mark Evans says the project is tracking well but, as with many things, “the devil is in the detail”.
A small amount of asbestos-contaminated fill was found in Rosebank Domain and had to be removed, adding cost and a time delay to that element of the project. However, Mark says savings have been made elsewhere – the team has been able to source fill from a number of nearby projects which means a reduction in transport costs, and they obtained some rock material from a site in south Auckland at no charge.
Mark says the design and construction are going pretty much to plan. He is particularly proud of the Causeway Alliance’s exceptional compliance figures.
The project has a long list of requirements to tick off largely because the road passes through the Motu Manawa-Pollen Island marine reserve, which requires additional environmental consideration. Auckland Council inspectors have scored the site ‘one’ (the highest possible score) 196 times in 197 inspections, and ‘two’ just once.
Other environmental successes include innovative design solutions resulting in fewer earthworks and a smaller embankment footprint; installing stormwater treatment devices that remove 80 percent of suspended solids; and significant weed clearing beyond the boundaries of the project.
The local fauna seems largely unfazed by the large machinery in its backyard, with bird numbers up from data recorded this time last year. In October, one of the project team photographed a New Zealand fur seal frolicking around the piers of Whau River Bridge as work went on above.
In addition to the environmental considerations, the site is a narrow corridor adjacent to high-speed motorists, which brings extra safety risks.
These risks are being carefully managed and with such success that the Causeway Alliance team has scooped the NZ Transport Agency’s 2014 Going the Extra Mile (GEM) award for health and safety innovation.
The project’s superintendent, Jamie Colquhoun, also recently won a national environmental leadership award for his work.
Although impressive to travellers on the Northwestern Motorway, the causeway project is somewhat overshadowed by the spectacular Waterview tunnels next door.
In late October, excavation of the 2.4 kilometre-long northbound tunnel was completed. The tunnel borer is currently being turned (a tricky engineering job in itself) and will soon start work on the southbound tunnel. This should be finished by October next year.
As part of the tunnel contract, the Waterview Connection project includes building surface connections to the existing motorways. The motorway interchange with Great North Road will have four new ramps. The team is currently working on Ramp 3, which will take westbound traffic from SH16 into the tunnel. This flyover should be finished by the end of the year.
The team is also constructing nine kilometres of new cycleway and new community amenities such as playgrounds and walkways.
Along with the causeway and the tunnels, another three adjacent projects are also in progress: the Te Atatu Road interchange; the Lincoln Road interchange; and the Great North Road-to-St Lukes motorway upgrade.
At Te Atatu, work has begun to upgrade all five interchange ramps. In November the first of three stages to raise the Te Atatu Road overbridge was completed to create more clearance for the motorway beneath. The bridge will also be widened to allow an extra lane in each direction.
Users of the Lincoln Road interchange are already enjoying the realigned and wider on ramps and exit lanes.
.All five contracts underway to complete the Northwestern Upgrade are linked but being undertaken by three different teams, so one of the biggest challenges is ensuring excellent communication between the project teams.
“It’s an integrated programme with lots of traffic shifts. We’ve got good people working on the detail,” says Mark. The motorway from St Lukes Road to Great North Road is being widened to allow an extra lane of traffic in each direction. The St Lukes overbridge is also being replaced. The new, higher and wider bridge will also have an extra lane in each direction for motorists and improved facilities for walkers and cyclists
“We have management, operational and governance meetings frequently to ensure we know who can do what and when.
“A lot of planning has gone in to get this right.”
All five projects of the Waterview Connection and Northwestern Upgrade are due to be completed by early 2017 when the Transport Agency plans to have the tunnels open to traffic.
The Western Ring Route project will be fully complete when the Lincoln Road-to-Westgate and Upper Harbour Highway upgrades are finished, and investigation is currently being completed to bring this last component forward.