Wellington running out of rocks
The region is fast running out of one of the building blocks needed to fix its broken water infrastructure and build new roads.
Ross Baker, the manager at Horokiwi Quarries, said Wellington desperately needed new sources of aggregates.
It was a problem he believed had flown under the radar but with Horokiwi’s life expectancy of eight to 20 years, there was a need to plan for the future.
“People are pretty ignorant about it and just seem to think quarries will always be there ... everything that is built uses aggregates – fixing Wellington’s (water infrastructure) needs aggregates.”
Wellington’s geography added to the problem, and he said bringing in material from outside the region doubled the price.
Aggregate and Quarry Association chief executive Wayne Scott said the future was not looking good for Wellington.
The region needed new quarries, and to extend the life of its two existing quarries – Horokiwi and Belmont – but that was difficult as there was always staunch opposition.
Projects like Transmission Gully had been delayed or become more expensive due to the shortage of aggregates, he said. Aggregates include crushed rock or sand, and are used for example in roading, concrete and ground stabilisation.
The biggest project currently under construction in Wellington is the Ngā Ūranga ki Pito-One (Ngauranga to Petone) shared path and cycleway. Last April, Waka Kotahi estimated that it would require 144,000 tonnes of rock, a lot of which would be barged over from Golden Bay.
The Infrastructure Commission Te Waihanga was looking at the issue and he understood it had identified Wellington, Bay of Plenty, Auckland and Queenstown as areas with major shortfalls.
“They are high risk areas for running out of supply.”
Although Scott had called for the fast tracking of new quarries, he doubted the new powers the Government had given itself would have much impact.
A report from Graeme Campbell, Greater Wellington Regional Council principal advisor flood and resilience, said there was a need to plan for the future with a number of large infrastructure projects looming in Wellington.
“It’s crucial that we better understand, plan and utilise our aggregate resources to ensure our infrastructure providers have a reliable and affordable supply of aggregates and any impacts on the environment or our communities are managed.”
The need for aggregate was continuing to increase at the same time as existing sources of aggregate were running out.
Greater Wellington was working with the Infrastructure Commission to identify areas in the region that could be a source for aggregates in the future.
The data could be used in council planning documents to safeguard areas suitable for quarrying.
New Zealand uses around four million truckloads of aggregates annually. Identifying sources of aggregates could potentially reduce truck movements, which would reduce road maintenance and emissions, Campbell said.
The issue of a shortage of aggregates had first been raised with the regional council by Wairarapa councils.
Carterton mayor Ron Mark said the Wairarapa was already experiencing a shortage of aggregates.
The annual cost of maintaining Carterton’s roads had risen by 36%. Although there were number of potential local sources, the council’s contractors were being forced to barge rocks from the South Island. “It is very clear we are importing aggregate – rock and boulders – from the South Island, which is dumb and stupid.”
“People are pretty ignorant about it and just seem to think quarries will always be there ...” Ross Baker
Horokiwi Quarries manager