Talanx : Inching towards success

10 July 2017

HDI covered the 'Waterview Connection' project in New Zealand

In mid-2012 the New Zealand Transport Agency (NZTA) set in motion the country's hitherto 'largest and most ambitious road construction project': known as the Waterview Connection. The government entity puts the total project costs at 1.4 billion New Zealand dollars, equivalent to almost EUR 1 billion. HDI Australia participated in the bidding process - and was awarded the contract as lead insurer of the Well-Connected Alliance which has delivered the project for the NZTA on behalf of the NZ Government. At the same time, the industrial insurer thereby assumed responsibility for risk consulting and claims handling. HDI Australia is part of HDI Global SE, the internationally operating industrial lines insurer within the Talanx Group.

'Alice' and the tunnel excavation work

At a rate of eight centimetres per minute 'Alice' devoured a path through the ground under Auckland. A snail's pace? Certainly not: 'Alice' is a tunnel boring machine, or TBM for short, that has a diameter of 14.4 metres, a total length of almost 88 metres and weighs in at an impressive 3,200 tonnes. Over a period of two years the rotating head of this high-tech machine bored two 2.4-kilometre long tunnels through the ground - while some 20 to 45 metres above it, public life in Auckland, New Zealand's largest city, took its usual course. In the beginning of July 2017 the construction phase has been finally completed - and the twin tunnels opened for traffic.

Auckland is home to roughly one and a half million people. State Highway 1 had proven to be a chokepoint in this urban conurbation. The major north-south motorway, it links the region to the North Shore and opens up access to Auckland's city centre, ports and largest airport for commercial traffic and tourist travel. As a result, the highway - including the harbour bridge - was chronically congested. The Waterview Connection is designed to change this. The twin tunnels for vehicles travelling in both directions were joined - in part via a significant road interchange which included overhead viaducts and without interrupting traffic. The tunnels and interchange were the 'final link' to connect two other motorways and complete a second motorway through the city known as the 'Western Ring Route'.

HDI engineers and risk consultants on-site worldwide for customers

'Starting with the project planning phase, our customers and our underwriters around the world are actively assisted in all matters of risk prevention by our seasoned risk consultants working in the various geographical regions and at our head office in Hannover, Germany', explains Mr. Rolf Heyke, Underwriting Manager, Engineering for Australasia, who underwrote the transportation project with support from his colleagues in Germany. The risk consultants analyse hazards and risk exposures during construction site inspections, verify the implementation of agreed safety measures and monitor compliance with world best practice.

Project completion in July

Since the project launch, the Well-Connected Alliance has been comprehensively protected by a Construction All Risk policy against all engineering risks as well as damage caused by an accident, fire or natural hazards. The TBM, with a value of 52 million New Zealand dollars, was covered by a separate Plant and Machinery policy. There is a limited insurance protection period provided by HDI Global which now remains in place for a further two years after completion by including an extended maintenance warranty clause which covers defects in construction, design or materials that may have occurred during the construction phase on the project site, but which only manifest themselves after project completion. 'This could be the case, for instance, if an appreciable quantity of water were to penetrate the tunnel after protracted heavy rainfall - for example because the lining used to seal the tunnel was accidentally perforated during installation', adds Mr. Heyke.

Focus on geotechnical challenges

The risk analysis carried out by HDI Global concentrated on reducing the fire hazards, especially on the TBM. One of the tasks, therefore, was to minimise fire loads and the risk of sparks. The risk consultants also paid attention to the organisation of the construction activities, the building regulations, and the transportation and storage of materials.
Special focus was also applied to geotechnical considerations, such as the composition of the subsoil, earthquake risks and climate conditions. For example, it was important not to carry out significant excavations at certain times of the year when historically the heaviest precipitation was to be expected. Furthermore, the TBM's cutter head had to be customised for the structure of the soil layers.

Similarly, the consequences would have been significant if the TBM had struck an underground water path, thereby flooding the tunnel. The underground utility lines were absolutely critical, not least because the project was realised in an urban area. Avoiding boring errors in this regard was a point of emphasis in the team's work.

Interview with Rolf Heyke, Underwriting Manager Engineering - Australasia

What was special about this project?
Through the 'Waterview Connection' project, HDI supported the largest roading infrastructure project ever undertaken in New Zealand. A special feature for HDI, in common with many of the project participants, was the use of the world's tenth-largest tunnel boring machine 'Alice'. With a diameter of 14.4 metres and a total length of almost 88 metres, Alice weighs an impressive 3,200 tonnes. The boring machine not only excavated the rock and conveyed the material out of the tunnel, it also built the tunnel walls by cladding them with altogether more than 24,000 circular concrete segments, each weighing ten tonnes. The project presented a unique opportunity for HDI experts to demonstrate their worldwide expertise in the fields of underwriting, risk consulting and claims handling.

What were the greatest challenges?
The biggest challenge was the fire hazard, for example from sparks. Highly flammable operating materials were constantly present on the machine. Reducing the risk of fire was one of the most important objectives of our risk analysis. As part of the subsoil exploration it was also necessary to clarify issues relating to the groundwater level. Significant excavations cannot be carried out at a time when historically the heaviest precipitation is to be expected. Another focus was on quality assurance, for example with respect to the concrete.

In some instances the project team was called upon to show its creativity: during investigative drilling prior to construction a drill bit broke off - something which could have damaged Alice. The plan was for the two tunnels to be linked by multiple cross passages for the mechanical and electrical services that could also serve as emergency escape routes, should a fire break out in one of the tunnels, for example. The project team thus hit upon the idea that they could move the planned location of one of these cross passages, hence enabling them to approach the broken drill bit from the side and extract it.

Another exciting moment for everyone involved came when, after the first tunnel had been successfully bored, Alice had to be turned 180 degrees around in the tightest of spaces to bore the second tunnel. In order to do this she was dismantled piece by piece, turned around and then reassembled for the second tunnel.

What is your overall assessment now that the project is complete?
The project has been well executed by the project team who significantly valued our input by working together with our underwriting and risk engineering staff. Through targeted risk prevention and the systematic pursuit of improvements, we helped to ensure that this significant urban construction project progressed safely and without loss and, ultimately, we were part of the project's success.
Throughout the entire project our experts engaged in a continuous dialogue with the Waterview Alliance and were thus able to respond quickly to issues at the construction site. In risk consulting, underwriting and claims management, HDI employed expert risk consultants and engineers on-site who were familiar with the conditions and safety practices in Auckland. Because of this, we were able to maintain at all times a continuous dialogue with the project team, which in the final analysis was a crucial part of our involvement.

The NZTA expects that some 90,000 vehicles will pass through the tunnels every day in the future. This means that they will have to withstand a good deal of wear and tear.

You can also find further information on the HDI Global SE website.

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