Natural Hazards Indicators (what we measure)

Overview

• Flooding - extensive flood protection schemes have been implemented to minimise flood damage in the district.
• Erosion and landslides - important concerns in hill country in the district, particularly on the steep slopes of Mount Te Aroha, and along the Kaimai Ranges.
• Fire - from burning forest is a rare event within the district, but still poses a significant risk.
• Wind - can be a problem in areas adjacent to the Kaimai Ranges, and in known wind tunnelling areas.
• Peat Soils - represent a hazard because of the subsidence, fire and flood risks that are associated with them.

Our Situation

There are approximately 8091 hectares of land that has been identified by Council as being at risk of flooding. A ‘flood event’ is a mean annual event or higher. Whilst no flooding events have been recorded between 2003/04 and 2007/08, the district suffered three main flooding events from 2000/01 to 2002/03. In June 2002, a flood considered as a ‘one-in-twenty-year-event’ occurred; this ‘weather bomb’ caused damage to Council infrastructure estimated at a value of $263,500. In addition to this, another $1,467,200 worth of storm water upgrades were recommended to be undertaken by Council following this storm. There was also a one-in-five year flood event on the Waitoa River in July 2002 and a one-in-five year event on the Waihou River in January 2003. There were four significant flood events within the district during the 09/10 financial year. The most significant of these occurred in February 2010 on Old Te Aroha Road. This event resulted in the closure of Old Te Aroha Road and damaged a culvert and road guard rails. In 2010/11 there was no damage recorded to public and private property from natural hazards.

New developments in known hazard zones are potentially at high risk of being damaged by hazard events. Between 2000/01 and 2010/11, 157 resource or building consents have been applied for within the flood protection area in the district. All 157 consents were granted, subject to conditions to mitigate potential adverse effects. These consents were for activities such as building new garages, relocating dwellings, and upgrading buildings. There are approximately 290 buildings existing within the flood protection zone. No new buildings were constructed in the flood area in 2010/11; all consents were for excavation or minor upgrading of existing buildings.