Masterton's Flood Risk

Internal Affairs Report released this week that highlights communities most vulnerable to the effects of flooding – in which Masterton was named. Our responses follow:

• What areas of Masterton are most prone to flooding? Greater Wellington Regional Council maps indicate the areas their analysis shows are at greatest risk of flood. These maps are currently being updated, and we expect to have amended versions before the end of the month.
• How is this problem being mitigated? Our current measures, such as stop banks and using roads secondary run off, have protected the town to date. Greater Wellington Regional Council is in the process of developing updated flood maps for our district, and we will be considering those as part of future planning to ensure we can maintain effective flood control management
• Does the council have any long-term plans for managed retreat or flood protection in Masterton in the wake of Climate Change? The Greater Wellington regional Council maps will include a climate change factor – a vital consideration for the future of our district, as it is for the whole of New Zealand. Council recently adopted its Climate Action Plan, which outlines areas of focus for us to better understand the impacts of climate change on our district:
  • Action 55 of that plan outlines our approach to future planning for the local impacts of climate change
  • Action 59 and 62 of that plan outlines our approach to partnering with GWRC to mitigate future flooding risks
  • Action 66 outlines that Council will investigate how to assess climate change impacts for all new Council developments and infrastructure
• Can you please explain the effect Masterton being built on a flood plain has on the communities resilience to flooding? Any area built on a flood plain comes with risk, however Masterton District Council and the Greater Wellington Regional Council have put measures in place that have seen that risk mitigated effectively. For example, in 1978, a year in which we saw the Waipoua River run at its highest levels in memory, the stop banks were not breached, and the town did not experience any floods. As factors such as climate change are further considered, we will work with GWRC to ensure the protection measure we have in place continue to be effective.
• In the next 100 years, is it likely homes or areas will need to be abandoned? We hope not, however managed retreat is a consideration for managing the effects of climate change – particularly in our coastal areas which are at risk from more extreme weather events, rising sea levels and coastal erosion. Our priority at Council is to minimise risk to life and property in the event of a catastrophic event. The GWRC maps and our Climate Action Plan focus areas will help inform our ongoing planning around that