The problem

In the northern Murray-Darling Basin, many floodplain structures have been built without approval or don’t meet legal standards. They can block or redirect floodwater, stopping it from reaching important ecosystems, cultural sites, and downstream users.

Why it matters

Unauthorised flood works change how water moves across the land, often unpredictably. This can harm towns, farms, the environment, and cultural sites. Some structures also allow unlawful water use to happen, reducing the amount available for legal users. Removing the worst of these helps protect river health and ensures floodwater reaches places like the Menindee Lakes and Macquarie Marshes.

Our approach

With funding from the Commonwealth ($10.2 million) and NSW Government ($1.08 million), we joined a multi-agency effort to address unauthorised flood works in 5 valleys with existing Floodplain Management Plans.

We inspected more than 100 properties and used satellite data and flood modelling to assess the impact of the flood works. High-risk cases were referred for further investigation and possible removal.

We worked directly with landholders to understand how these structures were used and to find solutions. Some works were removed entirely, while others were modified to meet legal requirements under the Water Management Act 2000.

Our approach balanced enforcement with education, aiming to improve long-term floodplain health and compliance.