Neither the Ministry of Transport or the Transport Agency have investigated the overall impact their multi-billion dollar roading projects will have on the country's greenhouse gas (GHG) emissions, according to official information.
Transport emissions make up nearly a fifth of the country's emissions profile, and is among the fastest growing sectors.
In official information given to the Green Party, the Ministry of Transport and the Transport Agency were asked for any analysis of the impact that the government's investment in the land transport system would have on greenhouse gas emissions from transport.
The Ministry and Agency replied that no analysis or other documents were found, although the organisations said climate change across its investments was being considered.
The Green's transport spokesperson, Julie Anne Genter, said it was shockingly irresponsible that the government was planning a $30 billion spend over the next ten years on transport infrastructure, and no thought had been given to climate pollution.
Earlier this year, New Zealand signed the historic Paris agreement and committed to reduce GHG emissions to 11 per cent below 1990 levels by 2030, through a number of measures, including reducing domestic emissions.
Ms Genter said after the Paris agreement, the government knew that fossil fuels needed to be phased out in the next few decades.
"That essentially means that every bit of infrastructure we build from now needs to be taking us in that direction of zero carbon, but National isn't even planning for that ten years out into the future - they have no idea what the impact of their spend is going to be."
The Green Party also put in a series of written parliamentary questions to the Transport Minister Simon Bridges - who is also the associate Climate Change Minister - on the advice he had received on what emissions would do as a result of three major roading projects in Waikato and Auckland.
He had not received any, but said he hadn't asked for any either.
"In relation to all of these roads of national significance I haven't requested advice.
"I'm broadly aware though that, as I say, in relation to the roads of national significance, such as the Waikato Expressway, and I think will hold true across the roads of national significance, the effect of safer journeys, more efficient journeys and reduced congestion in fact reduces emissions."
When asked why he hadn't asked for advice on emissions, Mr Bridges said he had, in the sense that he'd had many discussions with transport officials and people on the operational end.
The Transport Agency has done some modelling on emissions as a result of the Waikato Expressway and predicts by 2061, carbon dioxide emissions will fall by 35,000 tonnes a year, to 1.8 million tonnes.
But Ralph Chapman, from Victoria University's School of Geography, Environment and Earth Sciences, said he was highly sceptical of the reduction figures, as a result of building faster and bigger roads.
He said they did not take traffic generation into account.
"So sure, individual cars or trucks might move a little faster and run a little more efficiently... against that you have a growth in the amount of traffic on those roads, and in fact that's what the government seeks to achieve because it's trying to grow the economy."
Professor Chapman said it was unfortunate that emissions was a secondary thought in the government's transport plans and its policies did not marry with the commitment made in Paris.