Niemur-Colligen early works and measures

Benefits of the works and measures

The potential benefits of the proposed early works and measures could include:

• higher environmental flows could be delivered in the flow corridor, benefitting wetlands and floodplains downstream and improving river and wetland health
• less overtopping of structures in times of natural high flows, resulting in better access and less disruption to landholders
• less servicing and maintenance as the infrastructure would be designed for higher flows
• less clean-up cost for private and public landholders due to less frequent overtopping of structures during natural flows.

Early works and measures limits

The frequency of managed environmental flows, enabled by the program, would vary over time depending on water availability, climate conditions, ecological priorities, and consideration of risks and impacts. These higher environmental flow deliveries would not occur during extreme wet conditions when there is elevated flood risk.

This package of works and measures will be designed to mitigate against flows up to and including the highest flow option (with buffer) being considered by the program. The package will not be designed to mitigate against natural flow events above this level.

Niemur-Colligen early works and measures scoping

The Water Group in the NSW Department of Climate Change, Energy, the Environment and Water is leading the preliminary concept design and geotechnical survey work.

Engagement with landholders, First Nations groups and other stakeholders will play an important part in the package’s development.

Scoping activities include:

• initial landholder and First Nations engagement
• developing an Aboriginal Cultural Heritage Assessment Report and necessary site investigations with Traditional Owners
• reviewing and undertaking ecological, Aboriginal heritage and environmental studies
• undertaking geotechnical investigations and hydraulic modelling to inform works design
• concept designing and cost estimates of mitigation works.

Works that do not meet eligibility criteria will be out of scope for this early works and measures package. Any properties outside the Niemur-Colligen early works and measures package will be considered as part of the broader program’s delivery.