The overall objective of the Burrawang to Avon Tunnel (BAT) project is to improve environmental outcomes, provide greater certainty and security of water supply to WaterNSW customers, and to help meet the demand of Greater Sydney’s future population growth.
The BAT project is the final piece in completing the NSW Government’s decade-long strategy for restoring river health and protecting environmental flows for the Shoalhaven Transfer System.
The BAT project includes:
- 19km, 3.5m internal diameter tunnel from Fitzroy Falls Reservoir to the Avon Dam
- The design capacity is 1800 ML/d on intermittent flows
- Allowance for increased active storage of the Avon Dam by 65GL
- 9km spur pipeline from the upper reaches of the Avon Reservoir to the Illawarra Water Treatment Plant, which supplies water to Wollongong.
WaterNSW engaged us to identify the preferred scheme and to develop the concept design to transfer water from the Shoalhaven supply area to the Greater Sydney supply area, via the BAT. The scope included:
- Option selection process using multi-criteria assessment methodology
- Geotechnical site investigation with boreholes to a depth of 300m
- Concept design of the water transfer scheme
- Feasibility and concept design of hydroelectric power plant (HEPP) to be constructed and financed by a commercial enterprise in the future.
Once complete, the BAT will:
- Maintain river health and protect environmental flows in the catchment
- Improve water security to the Sydney and Wollongong supply areas
- Reduce pressure on the Warragamba Catchment, Sydney’s key water supply source
- Provide an opportunity for future hydropower generation, as there’s approximately 200m head that can drive the power generation turbines.
The project is currently on hold and will be considered as part of the broader Greater Sydney Water Strategy that is currently being developed. The strategy will be completed by the end of 2020 and WaterNSW will update stakeholders and the community regarding the future of the project at that time.