Extending Warkworth to Wellsford, Cambridge expressways could boost New Zealand's GDP by nearly $500 million per year - report

A new report claims extending two expressways could boost New Zealand's gross domestic product (GDP) by nearly $500 million per year. 

The report from an infrastructure advocacy group says extending the expressway from Warkworth to Wellsford north of Auckland, as well as the one south of Cambridge would massively boost GDP and productivity.  

The Northern Infrastructure Forum (NIF) is calling for expressway extensions to be prioritised under the next government after the report it commissioned found the Warkworth to Wellsford extension would reduce travel time by up to 16 percent. An extension to the expressway between Cambridge and Piarere, meanwhile, could reduce travel time by 18 percent. 

Faster freight would open the door for better productivity, which could lead to more businesses being able to operate and contribute to New Zealand's GDP, the NIF said. 

NIF coordinator Barney Irvine said investing now is key for future generations. 

"The reality here is, if we don't meet that demand through building new roads, we don't really have an alternative. Sure, we need to put more money into rail [and] into coastal shipping to accommodate freight demand but if we aren't supporting roads, geez we're going to have real problems," Irvine told AM on Thursday. 

He pointed to the fact both major political parties had committed to the mentioned projects and said completing them as soon as possible was crucial. 

"It's one thing committing to a project and another thing actually doing it," he said. 

"I guess what we really want to see from the next government is a commitment to funding and a commitment to a timeframe." 

The NZ Institute of Economic Research (NZIER), which carried out the report, noted its traffic volume and employment benefit calculations were based on pre-pandemic trends.  

"Nonetheless, in the context of a transport infrastructure investment spanning several decades, we consider this a minor risk." 

While the economic returns during the projects' construction would be moderate, the benefits to the wider economy would be "long-lasting" once they become operational, the NZIER economists found. 

"Each investment will deliver economic gains of over $6 billion over the first 20 years of their operation," the research concluded.  

"This is a much greater return compared to the initial capital expenditure during their construction." 

Labour last month proposed increasing fuel taxes by 4 cents per litre every year for the next three years to help pay for improvements to New Zealand's transport network, while National in July unveiled a $26 billion 'Transport for the Future' plan - which leader Christopher Luxon said would be funded reallocated cash from the National Land Transport Fund, further Government investment and other tools.