Designated Flood Level for Residential Buildings

The outcome of the flood search is the Designated Flood Level, which is reported in metres AHD (Australian Height Datum), generally refers to mean sea level. Therefore the Designated Flood Level of 1.5 metres AHD is approximately equivalent to 1.5 metres above mean sea level. The Designated Flood Level is used determining floor levels for hotel residential, education facilities, residential buildings, camping grounds, caravan parks, relocatable homes reclamation levels, commercial, light industrial and warehouses as defined in the flood overlay code. To ensure a resilient Gold Coast, the City requires that habitable floor levels for residential buildings be at minimum of 300 millimetres above the Designated Flood Level. Other information (if available) is also provided: Estimated ground level and historical floor levels. For further information, please refer this link. Flood Information Important Note: The Designated Flood Levels are simulated riverine or regional flooding from a computer model, and it does not consider local flooding. The statistical 100 year AEP (Annual Exceedence Probability) is used for regional flooding which is basically heavy rainfall over the water catchment for long periods of time causing major rivers or creeks to over-top and inundate the floodplain. Local flooding, on the other hand, is high intensity rainfall over a short period of time. A flood the size of a 100 year AEP has 1% chance of occurring in any one year. As rainfall events are random and there is no guarantee when such a flood will occur, or that how many times it will occur in any year.