A floodplain is an area of land adjacent to a creek, river, estuary, lake, dam or artificial channel, which is subject to inundation by floodwater. Most cities and towns in Queensland, for example, are located on floodplains. There are ample benefits associated with making use of fertile floodplain lands, but they come with an obvious drawback: by definition, floodplain land is subject to flooding.
A flood study is the scientific investigation of flooding in a particular area, usually the catchment of a river system. It may involve hydrologic and hydraulic investigations, and a statistical analysis of the frequency with which floods have occurred. The purpose of a flood study is to predict the height of water and the extent to which it will inundate the landscape in a modelled flood event.
A flood map is the visual representation of the information contained in a flood study. It is the final outcome of a multitude of measurement, engineering, and data analysis tasks. The elevations of the land, water, and hydraulic structures (such as bridges) are key elements in a flood study, and the accuracy to which these elements are determined is a critical factor in the accuracy of the final flood map.
Flood modelling estimates where rain water will run, given the location, intensity, frequency, duration and extent of rainfall, the topography and the various features of the built environment such as dams, levees and sealed surfaces. Topography details are incorporated into flood models using information from digital terrain models that show the height of the ground surface.
Risk is formally defined in ISO 31000 (2009) as the 'effect of uncertainty on objectives'.
In November 2011, the Standing Council on Police and Emergency Management endorsed the National Emergency Risk Assessment Guidelines (NERAG) as the consistent methodology for future use by Australian governments.
Flood risk information may include flood studies, flood maps; the products of flood modelling, and relevant and related data.
In line with the NERAG, flood risk would be determined for a range of scenario events. These scenarios would span a frequency range to support the reason for the risk assessment.
Flood risk management comprises flood risk measurement and flood risk mitigation. Improved flood risk measurement and flood risk mitigation are important for both the future welfare of the community and the continued development of the market for flood insurance.
Flood risk measurement, including flood mapping and flood modelling in their various forms, enables flood risk to be estimated and understood, which assists assessments and decisions regarding flood risk mitigation and flood insurance.
Spatial data infrastructure is an interacting system of basic geographical data, spatial information services, technical standards and specifications and an institutional framework.
Topic contact: firstname.lastname@example.org Last updated: January 22, 2013