Tweed Council adopts new flood study

TWEED Shire Council has taken a significant step forward in mitigating flood risks in the Tweed Valley, having resolved to adopt the Tweed Valley Flood Study Update and Expansion 2024.

The report from the Director of Engineering, which also acknowledges the recent release of topographic and bathymetric datasets for Tweed Shire by CSIRO as part of the Northern Rivers Resilience Initiative, was adopted unanimously.

Several flood studies and updates have been completed for the Tweed Valley over the past 15 years against the backdrop of Tweed’s long flooding history.

The latest update is the most detailed and comprehensive flood study ever conducted across the Tweed.

The NSW Government Floodplain Management Program, managed by the Department of Climate Change, Energy, the Environment and Water, has been a crucial partner in the Council’s efforts to mitigate flood risks. Its support enabled the Council to undertake the expansion, which builds upon the existing 2009 flood study.

The expanded research now includes the upper parts of the valley, including the villages of Tyalgum, Chillingham, Uki and the surrounding rural areas for the first time.

It also incorporates the latest advice from the national guideline, Australian Rainfall and Runoff.

Key elements included hydrologic model updates and adaptation, hydraulic model development and expansion, hydraulic model calibration, incorporation of the 2017 and 2020 events, and design modelling.

As part of the project, the hydraulic model was verified using the most recent February 2022 flood event data to improve the Council’s understanding of flood behaviour and the impacts and risks of different-sized events.

The adoption of the study now allows the Council to proceed to a Risk Management Study and Plan update to examine improvements in flood risk management, provide sensitivity testing of the model, and further validate the study.

For more information, visit yoursaytweed.com.au/flood-study