A Wellington quarry development that could look like "a bit of a scar" is set to deal with the city's rock shortage.
The Kiwi Point quarry, which is sat just off State Highway One in the Ngauranga Gorge, has supplied rocks - or aggregate - for the city since the 1920s.
The quarry ran out of aggregate in 2020, which triggered a shortage and led to about 200 extra trucks transporting the material into the Wellington region each day.
The rocks are used for most infrastructure projects such as roads, offices, housing and bridges.
Wellington City Council owns the site, and it is operated by contractors Holcim.
To curb the extra emissions caused by the trucks and to bring the important resource close to major infrastructure projects in Wellington, a business case is underway to develop the quarry's southern side.
The council's transport and infrastructure manager Brad Singh said that the business case would look three options for the quarry's operating model.
They were to run the expanded quarry with the same operating model; for the council to run the site itself; or setting up a trading organisation to run it.
He said the options were likely to be put before councillors in the next few months, with an expansion potentially able to start in the next two years.
The Kiwi Point quarry in the Ngauranga Gorge. Photo: RNZ
Singh told RNZ it would cost about $10 million to set up the expansion and would likely make about $300 million over the course of the new quarry's life.
He said there would be a time where the expansion might look like "a bit of a scar on the city".
"At the end of the day, this is something that is needed to prop up the city and the city's expansion."
The northern side of Kiwi Point, which ran out of aggregate, is currently being filled and will become flat land zoned for industrial sites.
Across the Wellington Region there is a shortage of quarries, which is a problem the Wellington Regional Leadership Committee - a group of council leaders across the region set up to drive regional economic growth - commissioned research on.
The work involved partnering with GNS Science to identify spots around the region where it could be worth establishing a quarry.
The group's programme director Kim Kelly told RNZ they would look at the location of those sites in relation to where large infrastructure projects will be over the coming decades.
She expected the work to be complete in four to six months.
