Purpose: This data has been published to support the Waikato Regional Hazards Portal. This data is part of the coastal hazards theme.Statement:"SURVEYED INUNDATION EXTENT": This data is presented as vector point data which shows the surveyed inundation extent for the 4-6 January 2018 storm surge event. Attribute information includes the elevation of the ground level at each survey point (in various datums) – these elevations do not necessarily represent the maximum level that the water reached, although they may provide an indication. Post event data collection was undertaken by a variety of field teams and then collated into a mapped area by Waikato Regional Council (WRC). These were collected by the WRC Environmental Monitoring (EM) team, who visited some rural sites and mapped burnt pasture lines. The WRC EM team also visited sites along the western Coromandel Coast mapping inundation extent points in townships where possible from Port Charles to Tararu. This was combined with some anecdotal water level reports collected by Thames Coromandel District Council during their post-event inspections. This data shows the significant amount of damaging inundation along the Thames Coast Road, as well as substantial impacts to residential (particularly at Waiomu, Te Puru and Kaiaua), and rural (Kaiaua/Miranda Coast) areas. Land elevations that the inundation affected varied across the area dependent on local topography and hydrodynamic effects. Surveyed debris/burnt pasture lines caused by inundation from the event varied in average elevation from RL 1.2 m on the southern Kaiaua/Miranda Coast to 3.0m across the Hauraki Plains. The maximum elevation of the surveyed inundation lines was at 5.7 m (TVD) at Ngarimu and Whakatete Bay, if accurately identified this is likely due to wave effects.APPARENT INUNDATION EXTENT (based on pasture burn): This data is presented as vector polygon data which shows the inundation extent along the Kaiaua Miranda coastline from the 4-6 January 2018 storm surge event, as represented by pasture burn (dead pasture due to salt water inundation). The polygons were mapped based on pasture burn shown on aerial imagery that was captured soon after the event, in early 2018. The digitisation of the pasture burn was completed by the Waikato Regional Council (WRC) Regional Hazards Team. Where the pasture burn lines were unclear, LiDAR (elevation) data and the surveyed inundation data was used to assist with mapping. The inundation extent has often not been mapped in built up areas due to the difficulty of identifying pasture burn in these areas. The lack of a desktop inundation extent polygon covering an area does not necessarily mean that inundation did not occur in this area. The presence of a desktop inundation extent polygon does not necessarily mean that inundation did occur in this area.Intended Use Scale: Surveyed inundation extent data should not be used at scales greater than 1:1,250 and apparent inundation extent data should not be used at scales greater than 1:2,500.Data Use Limits:This dataset is indicative. Coverage of an area by mapped apparent inundation does not guarantee that inundation occurred in this area, nor does non-coverage guarantee that inundation did not occur.WRC Metadata: Search for "HAZARD.sdeadmin.HAZ_PREV_EVENT_APPARENT_EXT" in HAZARDS - Regional Hazards Portal - GIS Layers and"HAZARD.sdeadmin.HAZ_PREV_EVENT_SURVEYED_EXT" - HAZARDS - Regional Hazards Portal - GIS LayersData Specific Disclaimers: This dataset is indicative. Coverage of an area by mapped apparent inundation does not guarantee that inundation occurred in this area, nor does non-coverage guarantee that inundation did not occur."The presence of a hazard does not guarantee the existence of such a hazard nor does the lack of information preclude the existence of a hazard or risk. Waikato Regional Council accepts no liability or otherwise resulting from hazards or knowledge of hazards."The standard Waikato Regional Council Disclaimer applies to this data “While Waikato Regional Council has exercised all reasonable skill and care in controlling the contents of this information, Waikato Regional Council accepts no liability in contract, tort or otherwise howsoever, for any loss, damage, injury or expense (whether direct, indirect or consequential) arising out of the provision of this information or its use by you.”Terms of Use:This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License.Should users wish to distribute or publish derivatives or modified versions of this data then they must seek a data use agreement through WRC first.See the Waikato Regional Hazards Portal Terms of use here Waikato Regional Hazards Portal - Terms of use | Waikato Regional Council.
