Cyclone Bola strikes

Cyclone Bola, one of the most damaging cyclones to hit New Zealand, struck Hawke’s Bay and Gisborne–East Cape in March 1988. The weather system slowed as it moved over the area, bringing torrential rain for more than three days.

Worst affected was the hill country behind Gisborne, where winds forced warm moist air up and over the hills, increasing the rainfall. In places, more than 900 mm of rain fell in 72 hours, and one area had 514 mm in a single day – more rain than parts of Central Otago get in an average year.

The ensuing floods overwhelmed river stopbanks, damaged houses, swept away bridges and sections of roads and railway lines, and destroyed parts of Gisborne’s main water-supply pipeline. Three people died in a car that was swept away by flood waters, and thousands were evacuated from their homes – 3000 in Gisborne, 300 in Wairoa, and 400 at Te Karaka.

The downpours triggered innumerable landslides on the region’s hillside pastures. Some farmers lost 30% of their grazing area, with landslide scars taking decades to heal. Huge quantities of sediment were swept away in the flood waters. One 11,000-hectare catchment deposited a million tonnes of sediment into the Waipāoa River. Thick sediment from the ebbing floods smothered pastures, orchards, and crops that had been ready for harvest. Cyclone Bola was estimated to have cost $90 million (equivalent to $170 million in 2016) in losses to horticulture and farming, and the cost to the government was more than $111 million ($210 million).

Text adapted from Te Ara

Image: still from Cyclone Bola film (Te Ara)