The study identifies that the various factors affecting the lake combine in an infinite number
of different ways that vary over time to produce different flood events. The terrain around the lake also determines the extent and depth of flooding from site to site e.g. low lying areas are more susceptible.
Following analysis of all the factors the study has identified two potential hazard zones. An initial “inundation hazard zone” based on those areas which are likely to be covered with water and a second “wave hazard zone” which identifies areas above the inundation zone where wind causes waves to push water up onto the land. In both zones there is a 1% chance that this flood level could be exceeded in any one year (1 in 100 year flood event).
The two zones have been separated because future development in either zone may need to have different planning and building controls applied to reflect the different risks. Both hazard zones include adjustments for the estimated effects from climate change and tectonic movement over the 100 year timeframe.
Tonkin & Taylor have peer reviewed the methodology used to identify the flood hazard zones and consider that it is suitable given the complexities of the factors influencing the lake when it floods.
Maps showing the hazard areas are being prepared for each of the settlements areas around the Lake Taupo foreshore. In line with legislative requirements, once the Council is satisfied that the mapping accurately reflects the reality on the ground, the new flood information will be included on Land Information Memoranda (LIM) and Project Information Memoranda (PIM) for affected properties. Letters will also be sent out to property owners in the affected areas informing them of the study findings and how their property might be affected. Further information on specific properties around the entire lake foreshore will be available once maps are completed.
Mayor Rick Cooper says the flood study findings will be used by Taupo District Council in consultation with communities over coming months to confirm appropriate planning measures.
“In the meantime we are legally obliged to include the new information on LIMS and PIMS,” he said.
Mayor Cooper and Environment Waikato’s Taupo representative Laurie Burdett say the new flood hazard information will allow both Councils to be proactive when it comes to protecting people and property from the risks of future flooding.
Mr Cooper said that changes may ultimately be needed to the Taupo District Plan to ensure that development in areas affected by flooding could be appropriately managed. While work has only just commenced on what those potential changes could be, Mr Cooper suggested that they might include things like controlling the floor height or location of buildings.
Council staff will be on hand to talk about the findings in the Lake Taupo Flood Hazard Study and the recently completed Lake Taupo Erosion Study at open days
- Tues 8 April, 12 midday to 7 pm at the Great Lake Centre, Taupo
- Wed 9 April, 12 midday to 5 pm at the Turangi Service Centre
- Thurs 10 April, 12 midday to 5 pm at the Mangakino Council Offices
- Sat 12 April, 10 am to 3 pm at the Acacia Bay Hall, Taupo
Final recommendations and actions will be included in a Lake Taupo Erosion and Flood Strategy that is due for completion towards the end of the year. Formal public consultation will be sought before the Strategy is adopted for implementation in the 2009/2010 financial year.
For further information contact:
Project Manager Erosion and Flood Strategy (TDC)
Nick Carroll
07 3760899
Taupo Mayor Rick Cooper
Ph: 07 3760830
Environment Waikato Taupo representative
Laurie Burdett
Ph: 07 3783025