The Lachlan River is subject to periodic flooding. There is an extensive and complex network of creeks and secondary waterways that run generally in a "big" river. When flood conditions are reached these waterways spill and a wide rural floodplain is created. In flood conditions the water is slow-moving and floodway are many kilometres across.
Council established a Rural Floodplain Management Committee and working with the community and State Government have developed a Rural Floodplain Management Plan, titled Lachlan River - Lake Brewster to Whealbah - Rural Flood Study (2006) (PDF). Implementation of the plan has seen a wide range of works across the floodplain by Council and also land-owners working in partnership. Works have included:
- removal of levees and irrigation channels,
- clearing waterways & depressions and
- providing new major pipes and road culverts.
The objective of all these works have been to return the floodplain more to its natural state and permit the flood to run freely.
Note: A 1:100 year Average Recurrence Interval flood does not mean it will only occur once every hundred years. It means that there is a 1:100 probability (chance) of a flood occurring in any twelve month period. Given the right climatic and catchment conditions more than one 1:100 year flood could occur in any year.