wharekawa coast 2120
TRANSCRIPT
Key findingsOverall impacts
ARP 200yr 100yr 75yr 50yr 20yr 10yr 5yr 2yr 1yr 6mth 2.4mth
Major event X
Moderate event X
• The community risk threshold for the major event is reached at a 10-year average return period.
• The community risk threshold for the moderate event is reached at a 2-year average return period.
• The thresholds are reached at these frequencies due to impacts to homes, properties and disruption to residents and, to a lesser
degree, impacts to road access. • Neither the major or moderate event thresholds have been
reached. • Due to projected sea level rise, the community risk threshold is
expected to be reached in the short term (10-30 years) for the moderate event.
A community risk threshold is the point at which the community can no longer tolerate the impacts of a natural hazard event. Adaptation actions or pathways should be implemented prior to a community risk threshold being reached.
Questions or comments?If you have any questions or comments about the community risk threshold results, you can email Sophie Marsh from Waikato Regional Council at [email protected].
You can also talk to your Community Panel – a list of panel members is on the Wharekawa Coast 2120 project website.
ContextIn June-July this year, the community was asked to participate in an exercise to assess their thresholds for coastal inundation in the Wharekawa Coast 2120 project area.
Community members were asked to individually assess community risk thresholds for the area, or sub-compartment that they live within.
They were asked to assess thresholds for:
1. Homes and properties, and disruption to residents2. Rural land3. Roading and bridges (road access)4. Services5. Recreation and tourism6. Overall impacts
Here are the results, as promised, for coastal inundation at Waharau (sub-compartment 5a)
Median results for each impact category
Homes, properties & disruption to residents
Rural land Road access Services Recreation & tourism
Overall impacts
Estimated time till overall impacts threshold reached
Major event threshold ARP (average return period)
10 years 2 years 5 years 1 year 2 years 10 years Long (50-70 years)
Moderate event threshold ARP
Not assessed due to non presence or non exposure to flooding
1 year 1 year Not assessed due to non presence or non exposure to flooding
6 months 2 years Short (10-30 years)
Key comments from community• Losing road access has been a major issue with slips to the north
and bridge/road closure to the south, particularly for access to emergency and other services and for the elderly. This will happenagain. Improve the bridge before the next event happens.
• Rain from the hills is a big concern (more than coastal inundation),causing water runoff, falling trees, slips and soil erosion. This needs to be mitigated and the trees cut back. Drain clearance and maintenance needs to be improved.
• The community is used to dealing with flood events, is self-reliantand helps each other. Insurance has been/will be a problem.
• There was not enough assistance after the 2018 coastal inundation event. The Waharau bridge damage in 2017 was handled very well.
• The mussel farms will increase fishing, traffic and rubbish and mayaffect coastal processes.
WHAREKAWA COAST 2120Waharau (sub-compartment 5a)Community risk threshold results for coastal inundation
Major eventModerate eventCoastal inundation event scenarios