Our second feature on the Roads of National Significance looks at the completed Tauranga Eastern Link and the protracted settlement over local network rehabilitation, which is a lesson for future RoNS. By ALAN TITCHALL, and based on a presentation at the 2016 Road Infrastructure Management Forum.
THE TAURANGA EASTERN LINK (TEL) opened to traffic in August 2015 as only the second RoNS project to be completed, following Auckland’s Victoria Park Tunnel in 2011.
Hailed as a success in terms of engineering, and completed ahead of schedule, none of the stakeholders involved foresaw the fight coming at the project’s end over putting the local network back in shape. While the principle of compensating local authorities for the use of their networks during project construction is not new, the scale of the RoNS project placed a high and disputed cost on this aspect of the build.
The $455 million TEL project delivered 21 kilometres of four-lane, median-divided highway between Tauranga and Paengaroa and took four and a half years to build.
The project involved 550,000 square metres of new road, three million cubic metres of earthworks, new intersections, and seven new bridges. The build involved 1.5 million working hours and numerous vehicle and machine movements.
It is acknowledged as one of the most geo-technically challenging major roading projects built in this country, due to soft ground conditions.
The TEL project team was made up of the Fulton Hogan HEB Construction Alliance (FHHCA), the Transport Agency, and Beca. Hard work and dedication saw construction completed five months ahead of schedule.
However, the clean-up after project turned into a protracted fight over the scale and cost of returning the local roading network, used as haulage and access points, back to its original condition, as agreed in the project consents. The parties concerned – the Transport Agency, the Western Bay of Plenty District Council (the local authority) and the contractors – could not agree over assessing the project impact (or consumption, as it is called).
The Western Bay of Plenty District Council, concerned from the start of the project over the impacts of project works on its local roading network, had sought consent conditions that compensated its ratepayers – in funds or physical works – for ‘consumption’. It is worth noting this large state project had been planned for some time, but work wasn’t expected for around 20 years. By this time, some ‘smart’ technology would be around to accurately determine the likes of consumption on existing networks. When the Tauranga link was brought forward as one of the seven RoNS, no so such technology was available.
By early 2015 the council and the NZTA started negotiating over the standard and condition the construction haul roads are in when handed back to council. The consent required local roads to have experienced “no loss of life”. As it told it rates payers in March 2015; “this is a complex discussion”. In fact the discussion went nowhere.
TEL contract parties agreed to employing a three-person team of experts to assess the impacts of construction traffic on local roads associated with the making of the TEL and find a fair and agreed mitigation cost. This team was made up of Alister McCaw, a senior asset manager with Beca specialising in road corridor maintenance, Dr Greg Arnold from Road Science, and Wayne Mackenzie from WestRoads.
Alister and Wayne made a joint presentation at the 2016 RIMS roading forum back in March this year called ‘Tauranga Eastern Link – Assessment of Local Roads Affected by Construction Traffic’.
“The problem was that at the end of construction with the focus on the build, there was no agreement as to what the impact on the local network was, only that there had been some impact,” says Alister.
“Worse – parties were many millions of dollars apart in cost impact – the contractor didn’t think there had been much impact and the local authority claimed a great deal of impact. And there were parties sitting in between. Each party seemed to be taking advice from their own consultants, who were wedded to a particular approach as to how you measure ‘consumption’ in a network.”
Using for a guide the original consent conditions, a combination of pre- and post-pavement condition data, Falling Weight Deflectometer (FWD) generated deflection data, and the forward works programme – they quickly discovered the limitations of so many methods and opinions within the industry as to how to assess pavement consumption, he says.
“There were a number of approaches we reviewed – all with their merits and weaknesses – but no one robust system that appeared fair to everybody.
“At the end of the day we needed to find a fair approach that all parties would sign up to.
“We took each approach and applied it – even the technical approaches – and weighed them, and this was quite a process,” says Alister.
On a basic level by looking at the performance and condition of the local network in 2011, when work started, and again in 2015 – any movement in that condition could be argued as ‘consumption’. More complicated was determining any change in the aggregate under the pavement that had to be compensated for.
“We are not smart enough these days to measure that, although some will argue we are,” Alister says.
Then there were the definitions in forwards works programme assessment of work traffic impact. The consent said all traffic, while the conditions said ‘construction traffic’.
The important thing in the forward works programme, comments Alister, is to agree to the ‘pre- and post-contract environment’ context.
If the consent simply says the network cannot be worse than what it was, you end up with years of debate and parties being aggrieved that they have been hard done by, he warns.
“Until we get a definitive way of measuring and being able to talk about the actual consumption in the network during a project construction we can be simple and remove uncertainty for the sake of the agency, the roading authority and the contractor.”
Wayne Mackenzie from WestRoads says the parties did reach agreement on the methodology and the amount of compensation for the TEL project, but the contractor felt it paid twice as much as it thought the mitigation was worth, while the council felt it was only getting half of the funds it needed to bring its road network back into it pre-project condition.
“From the council’s perspective three of the four local roads affected were old and in poor condition at the start of the project. We have a situation now where two of these roads have to be reconstructed and the cost is roughly twice the compensation amount.”
However, agreement is agreement and a lesson for all future RoNS projects.
Wayne iterates Alister’s view that there is no smart technology for deciding network ‘consumption’ during a project build.
“The technology available for analysing deflections is useful for pavement designers, but certainly lacks the accuracy necessary for contractually binding arrangements,” he says. “It cannot accurately determine the work or the necessary cost of pavement consumption.”
Recommending not relying on a ‘high-tech black-box analysis approach’, the team suggests a more black and white approach that is sealed into the contract at the beginning. For instance: “On completion of construction activities the following road sections shall receive the following treatments, and the following monitoring activities are to be undertaken during construction on the road conditions.”
“Get the contractor to nominate the haul roads they are going to use and what treatment they will receive at the end of the project,” says Wayne.
“The contract should also be specific about monitoring activities during the construction work to assess what’s going on, and ensure the contractors stick to the current condition of the road and keep it at the same level of service.
“All in all, we suggest a simple approach. Not a high-tech approach.”
• Next issue (June 2016): Part three.