Transport Minister Simeon Brown launched "The Case For Concrete Roads" report this morning commissioned by Concrete New Zealand and apparently an update of several previous reports:

Scoop: The Case for Concrete Roads was launched this morning by Transport Minister Simeon Brown. The report says concrete roads are on average 17 per cent cheaper over whole-of-life, reduce embodied carbon in roading and significantly reduce the cost and frequency of road maintenance. The report by consultancy Infometrics, commissioned by Concrete New Zealand, builds on reports from 2013, 2018 and 2020, to present a compelling case for the use of concrete in roading.

There is a pilot RCC Roller Compacted Concrete road you can try out on a section of Hamilton's Arthur Porter Drive finished earlier this year.

I'm guessing a concrete surface will initially use more sand than an asphalt surface. Initially that may mean an increase in unpopular sand mining.