A planting project adjoining Drury quarry in South Auckland is connecting isolated patches of indigenous forest over 55 hectares. Stevenson Aggregates’ commitment to managing environmental impacts is impressive for its scale, and attention to the conservation of locally rare plant species.

Fulton Hogan/Stevenson Aggregates owns and operates one of the largest quarries in New Zealand at Drury, South Auckland. The quarry produces more than 3 million tonnes of crushed greywacke aggregate annually, supplying roading and concrete markets in the Auckland and Waikato regions.

Set in rolling to moderately steep hilly terrain, close to Manukau harbour and the Hunua range, the quarry’s surrounding landscape is a mosaic of grazing land, remnant forest, and commercial and residential areas. Historically, the wider area was likely a mix of broadleaf, podocarp and kauri forest. Several remnants of native forest are present on Stevenson Aggregates’ landholdings; the largest is Ballard’s Cone (10 hectares), representative of a taraire, tawa, podocarp forest ecosystem.

Stevenson Aggregates has decided to offset the quarry’s environmental impacts by protecting, restoring and creating indigenous habitat over 55 ha. The aim is to improve the ecology of existing forest fragments and freshwater streams, and to eventually create a connecting ecological corridor. The company has engaged Auckland consultancy Envoco to carry out ecological restoration, which includes pest plant and animal control, planting, and ecological surveying.