Watercare's Hūnua and Waitākere Native Forest Catchment Protection (Auckland, New Zealand)

About 84% of Auckland's drinking water is collected from dams in the Hūnua and Waitākere Ranges, where largely native-forest catchments require comparatively little treatment before the water reaches the tap. Watercare, the council-owned water utility, treats this low-treatment-cost profile as a resource worth protecting: in 2017 it purchased forestry harvesting rights across former pine plantation land in the Hūnua Ranges, giving it direct control over land-use activities inside its own water catchments for the first time.

The resulting 30-year programme is regenerating more than 2,000 hectares of former forestry land with native trees and plants, with Watercare planning to spend at least NZ$15 million on planting alone; in one record planting season it put half a million native trees into the ground. The immediate trigger was practical rather than aesthetic — after the 2017 "Tasman Tempest" storm, hundreds of landslips on forestry land sent clay and silt into supply dams, making the water markedly harder and more expensive to treat, and underscoring the direct link between catchment land cover and treatment cost.

Separately, Watercare's more recent push to build a new NZ$400 million treatment plant inside the Waitākere Ranges to replace the ageing Huia plant has drawn public and iwi opposition over native tree loss — a reminder that watershed protection and new infrastructure needs can pull in different directions even within the same utility.

Read the full analysis: https://www.watercare.co.nz/home/about-us/latest-news-and-media/half-a-million-native-trees-planted-as-watercare-s-record-hunua-planting-season-wraps-up