Study background and local flood impacts
Why another study is needed
The Tweed Valley Floodplain Risk Management Study was prepared in 2014. It provided a regional understanding of the flood risk across the Tweed Valley along with recommendations on potential flood risk management measures to manage that flood risk. This previous study also acknowledged that it was a ‘catchment scale’ investigation and did not reliably reflect fine-scale details such as the Tweed Heads South urban area. Therefore, this study also recommended that more detailed, local drainage studies be completed to better understand the flood risk.
The Tweed Valley Floodplain Risk Management Study ultimately recommended the following measures and studies for further investigation:
- Commission local drainage studies - High priority
- Commission levee overtopping study - Medium priority
- Raise Tweed Heads South levee - Medium priority
- Extend Tweed Heads South levee to Philip Parade - Medium priority
The current project will directly address items 1 and 2 and will be a key step in moving towards the implementation of items 3 and 4.
The different flood types affecting Tweed Heads South
The Tweed Heads South study area is shown in the image below. It covers a total area of 15 km2 and can be impacted by 3 different types of flooding:
- riverine flooding is caused when the flow of water bursts the banks of creeks or rivers
- storm surge flooding is an abnormal rise in seawater level due to a storm
- overland stormwater or flash flooding is generated by rainfall running off towards the drainage or creek system.
