Gisborne Significant Flood Plains

The East Cape has a history of “hits” from decaying tropical cyclones causing widespread flooding and disruption. There are also other events that are more localised and result from a weather system dumping a large volume of water in a small area. A recent study showed that there is a trend of less of these events, but when they occur more rain falls. Most areas north of Ruatoria have a higher average rainfall than the south of the district and can cope with high rainfall events. The Waikura Valley for example can get 200mms in a 24 hour period without any adverse effects. The populated areas likely to be worst affected in a large event are the Poverty Bay Flats, Te Karaka and the area just north of Tolaga Bay. More intense localised events such as the 1985 Ngatapa flood and the 1977 Glenroy flood also caused substantial damage. Most of the Poverty Bay Flats, during inundation, is not subject to fast flowing water but huge areas are subject to ponding, which after the water recedes, will leave thick layers of silt damaging pasture and fences. In the city a number of riverbank properties are at risk. Extensive flooding depends upon the tides, potential overflow from the Waipaoa River, storm surges and the flood-peak times of the Taruheru and Waimata Rivers.

Data and Resources

Additional Info

Field Value
Theme ["geospatial"]
Maintainer GisborneDistrictCouncil
Created 2019-09-24T01:57:19.000Z
Date modified 2019-09-24T02:02:18.000Z
Language English
Spatial {"type": "Polygon", "coordinates": [[[176.8786, -38.8388], [179.0038, -38.8388], [179.0038, -37.5462], [176.8786, -37.5462], [176.8786, -38.8388]]]}
Source Identifier
Record created December 9, 2019, Last Updated March 3, 2020