Best practice development guidelines for flood prone land / Dept. of Natural Resources.

Highly Commended: Pre-disaster Category, Federal/State Government Stream, Safer Communities Awards 2006.

Natural disasters such as floods impose extensive social and economic costs on governments and the community. The Hawkesbury Valley in western Sydney is a rapidly growing area situated largely on a flood plain. With the increase in population in this area, there is an increased potential of risk to the community. The scale and magnitude of the Hawkesbury-Nepean flood problem in this highly developed valley became apparent during studies in the early 1990?s into the safety of the Warragamba Dam wall. The landforms have created a unique setting with the potential for isolating and totally inundating long established towns and villages. Entire towns and extensive suburbs lie well below the level of the probable maximum flood. The responsibility for the management of the floodplain is divided between six councils and many state government agencies. The Department of Natural Resources ?Guidelines? were produced to provide councils with a sounder basis for managing the severe flood risk to people and property when new development is proposed for flood prone land. The Guidelines promote: options for equalising the flood risk across graded floodplain areas and a more flood-responsive location of land uses which are more susceptible to flood damage; cost effective and straightforward modifications of current building practices to maintain structural integrity of new buildings subjected to flooding and; better solutions in road, lot and drainage layout for new subdivisions. The evacuation strategies and building practices outlined in the guidelines will reduce the flood risk within the Hawkesbury-Nepean Valley and save money and property in the event of a flood. The guidelines incorporate solid research for construction which is very practical and provides a useful suite of tools for floodplains. The use of the 1 in 100 year flood as the benchmark makes it a very detailed tool.