Biodiversity Offsetting under the Resource Management Act (New Zealand)

Under New Zealand's Resource Management Act 1991 (RMA), activities that harm indigenous biodiversity must first avoid, minimise and remedy their effects on-site; only residual, unavoidable impacts may be addressed through biodiversity offsetting or compensation. In 2014 the New Zealand Government — the Department of Conservation and the Ministry for the Environment — published "Guidance on Good Practice Biodiversity Offsetting in New Zealand" to standardise how consent authorities and applicants design, size and monitor offsets, built around a stated goal of "no net loss" and preferably a net gain of biodiversity.

To qualify, an offset must deliver measurable conservation gains — habitat restoration, protection or pest control — that are like-for-like or better than what is lost. Resource-consent case law shows the guidance applied across very different contexts: at Waikatea Station, a 799-hectare podocarp-broadleaf forest offset was accepted for consent to clear 354 hectares of kanuka scrub; at Lower Waitaki, wetland creation and enhancement offset a hydroelectric dam's impacts; and at the proposed Brookby Quarry, 112 hectares of revegetation plus 190 hectares of pest control were allocated across four ecosystem types as compensation.

The "no net loss" principle was reinforced nationally in the 2023 National Policy Statement for Indigenous Biodiversity, extending offsetting's role beyond individual RMA consents. Offsetting itself remains discretionary rather than mandatory under the RMA, applied case-by-case at the discretion of consent authorities and applicants.

Independent evaluation raises real doubts about delivery. A peer-reviewed compliance study of 81 New Zealand resource consents, covering 245 ecological-compensation conditions, found that 35.2% of those conditions were not being achieved in practice (Impact Assessment and Project Appraisal, 2013). Legal commentary on cases such as Bayly Trust also notes that courts have sometimes accepted offsets whose net conservation benefit was contested, illustrating a gap between the guidance's no-net-loss ambition and what is verified on the ground.

Read the full analysis: https://www.tandfonline.com/doi/full/10.1080/14615517.2012.762168