03 June 2021

Forestry: Nottingham Forest v. Unison

Unison Networks was awarded $195,000 damages from Hawkes Bay forestry companies following repeated power outages caused by trees falling across transmission lines running up Esk valley.

Unison’s network runs through some of the most heavily plantation-forested areas in New Zealand: Rotorua, through Taupo to Hawkes Bay. Its Esk feeder, running about 500 metres through a plantation of pinus radiata, suffered a series of outages from 2010 following tree strikes. Managing the forest, Forestry Management (NZ) Ltd refused to clear trees closest to transmission lines unless Unison paid.  Unison sued.

The Court of Appeal ruled forestry companies are liable in the tort of nuisance for outages caused by persistent tree strikes. In Esk valley, Unison’s transmission lines ran through the forest along a cleared thirty metre wide corridor. Planted out in 1994, the trees had grown to nearly forty metres in height.  Wind storms and snowfalls periodically pushed down trees.  Those trees planted on a slope had fallen over the transmission line, causing multiple outages over several years; the worst, a six day outage in 2016 affecting some 380 customers.

There was no need to prove Forestry Management was ‘at fault,’ the court ruled.  It was strictly liable.  The continuing occurrence of tree strikes amounted to a legal nuisance.

Nottingham Forest Trustee Ltd v. Unison Networks Ltd – Court of Appeal (3.06.21)

21.094