Natural Hazards

Natural HazardsNatural Hazards Indicators (what we measure)

 

Overview

Te Aroha Flood in 1985The district is subject to a wide range of natural hazards. Several significant natural events have been recorded that have caused loss of life, and damage to property and the environment. Our district’s hazards include:

Earthquakes and volcanic hazards – the Matamata-Piako District contains several active fault lines. Geothermal activity occurs at the hot springs at the Te Aroha Domain, the Opal Hot Springs near Matamata and the Okauia and Taihoa geothermal fields in the south of the district.

Flooding – extensive flood protection schemes have been implemented to minimise flood damage in the district.

Erosion and landslides – these are 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 – this can be a problem in areas adjacent to the Kaimai Ranges, and in known wind tunnelling areas.

Peat Soils – these represent a hazard because of the subsidence, fire and flood risks that are associated with them.

Our Situation

There are approximately 8,091 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. There were three weather events recorded in 2014/15. The most severe of these, on December 17, resulted in damage to house cladding and roofs in Matamata, Morrinsville and Te Aroha. Emergency crews also responded to branches blown on to roads, downed powerlines and a truck being blown over in Te Poi. Drivers were advised to avoid the Old Te Aroha Road due to high winds. In 2015/16, in a weather event on 31st July, flooding was recorded on Te Aroha-Gordon Road and the Old Te Aroha Road and a footbridge across the Waihou River was closed. In a weather event recorded from 31st December to 2nd January 2016, trees were blown over and there were four incidences of roofs lifting.

In April 2017, Cyclone Cook and Debbie caused widespread flooding. Matamata and Waharoa residents were asked to conserve water as the heavy rain caused flooding at a water treatment station, causing damage to pumps. A number of roads throughout the district were closed for several days and flooding to a number of buildings was reported.

In the 2017/18 year, two weather events caused flooding and road closures, particularly in rural areas. On 29 April 2018, there was flooding on the Te Aroha-Gordon and Old Te Aroha Roads and both Mace Road and Armadale Road were closed due to the Waihou River overtopping. On 6 June, the Ohinewai-Tahuna Road and the Te Aroha-Gordon Road were flooded, and Mace Road was again closed due to the height of the Waihou River.

Between 2010/11 and 2012/13 and from 2014/15 onwards no damage was recorded to public property from natural hazards. However, in the 2013/14 year, the 17th April flooding caused approximately $20,000 damage to Thompsons Track on the Kaimai Ranges.

 

Hazard Zones

New developments in known hazard zones are potentially at high risk of being damaged by hazard events. Between 2008/09 and 2017/18, 153 resource consents have been applied for within the flood protection area in the district. All of the consents were granted, subject to conditions to mitigate potential adverse effects. These consents were for activities such as building new sheds to house livestock or poultry, relocating dwellings, upgrading buildings and to build a jetty.

 


In 2016/17, and 2017/18, four and three resource consents, respectively, were approved on land subject to fire. These consents were granted subject to conditions to mitigate potential adverse effects. No resource consents were approved for either year on land subject to instability.

Since 2008/09 there has been a decreasing trend in the number of building consent applications within the flood protection area. This trend is representative of a decrease in building consents district wide. The most likely cause would originally have been the economic recession of the late 2000’s, although resource consent figures on land subject to flooding have remained low since then, despite the overall increase in consents, especially in 2015/16.

Erosion can also be a potential problem on the steeper slopes of the district. According to data taken from the 1992 Regional Indigenous Vegetation Inventory, there is approximately 20,686 hectares of vegetated land classified as having severe erosion potential in the district.

Rural Fire

Local Authorities no longer have any financial or operational responsibility for rural firefighting, as of 1 July 2017. The New Zealand Fire Service Act and the Forest and Rural Fires Act have been repealed and replaced by the Fire and Emergency New Zealand Act. 

Consequently, the data collection and reporting formerly completed for rural firefighting is no longer carried out.

Earthquakes

The table below shows the number of earthquakes recorded in the district each year, at a depth of 70 km or less. The 2010 District Plan Effectiveness Report notes that the District Plan includes an objective to minimise the risks of earthquakes affecting people and property in the district, but that research is not sufficiently advanced to permit detailed land use management and planning controls to be implemented to mitigate these risks. Data for 2012/13 was not available from GeoNet due to a changeover in their recording systems

Year

08/09

09/10

10/11

11/12

12/13

13/14

14/15

15/16

16/17

17/18

Number of Earthquakes

0     

2     

11    

9      

        

10*

 3*

7*

14*

2*

Magnitude of Earthquakes

 N/A

2.6

2.8

3.5

3.4

3.3

3.1

2.5

2.5

2.4

2.1

2.0

1.8

1.6

3.4

2.8

2.5

2.5

2.2

2.2

2.2

2.0

1.9

 

 

Between

1-3*

 Between

2-4*

 Between 

 2-3*

 Between 

 2-4*

Between

2-3*

 Source: http://www.geonet.org.nz/
*Geonet now depicts earthquake information in map form over specified time periods so the numbers and magnitude of earthquakes is an approximate figure.


What Council Is Doing

Council has identified 8,091 hectares of land as being subject to flooding in the district. New development on areas identified in this flood zone can be regulated by Council to prevent flood damage. Potentially unstable land has also been identified as a hazard within the Council’s District Planning Maps. There are approximately 11.3 hectares of this land identified in the district.

Civil Defence also plays a role in community protection. In 2011/12, 30 hours of Council time was spent delivering presentations to community groups and training of Council staff, and in 2012/13, 41 hours.

Additional presentations have been made by Civil Defence staff in each subsequent year. The financial value of these education sessions was not recorded as it is considered part of the core service of Civil Defence and covered by the levy paid to Civil Defence by Council. Council has concentrated on increasing emergency information on its website and increasing its presence on Facebook during natural hazard events.

The Waikato Regional Council completed a Natural Hazard risk assessment report for the Matamata-Piako District in 2014/15. The report provided an overview of natural hazards in our district as a basis for guiding and prioritising work activities for both the Matamata-Piako District and Waikato Regional Councils. This information will assist in the future review of the Natural Hazards provisions in the Matamata-Piako District Plan.

 

What You Can Do To Help

  • Keep your insurance cover up-to-date.
  • Ensure that your family has an emergency plan.
  • Know whether you live near potential hazard areas.
  • Have an emergency kit and drinking water ready at all times.

How are we Doing?

Anticipated Environmental Results

Natural Hazards

Achieved?

  • AchievingAchieving
  • Progress towards achievementProgress towards achievement
  • Not AchieveingNot Achieving
  • Not MonitoredNot Monitored
Negligible additional runoff from new development Not Monitored
Concentration of building development above a 1% flood level risk Achieving
Establishment of identified flooding and ponding areas within public open space Not Monitored
Increase in extent of catchment headwater vegetation cover Not Monitored
Negligible net increase in stormwater loads generated by development in flood prone areas Not Monitored
Concentration of building development away from high fire and wind hazard areas such as bush tracts, forested hill country and exposed ridges Achieving
No increase in the net cost of damage to persons and property through incidence of forest fire or severe wind events Not Monitored
No new habitable development in known high flood, wind, forest fire or land stability risk areas where mitigation cannot be readily or economically achieved Progress towards  achievement
Concentration of building development away from high land movement hazard areas such as steep exposed land, soft sediments and along eroding waterway margins Progress towards  achievement
No increase in the net cost of damage to persons and property through incidence of land movement Not Monitored
Increase in extent of bush regeneration and planting on erosion prone land Not Monitored
Increased awareness of the extent of earthquake and volcanic hazard affecting the district Not Monitored

Click here to learn more about District Plan Effectiveness and read the full report on Natural Hazards

Useful Links

Ministry of Civil Defence and Emergency Management

GeoNet

For More Information

Contact This email address is being protected from spambots. You need JavaScript enabled to view it. or
Customer Services
Matamata-Piako District Council
PO Box 266, Te Aroha 3342
Phone: 07 884 0060
Fax: 07 884 8865