There are a number of proposals for the expansion of agriculture and additional water supply infrastructure for our region, however, their viability depends on financial support, economic success of industry, environmental impacts and, most importantly, whether the allocable water exists (Gallant, et al., 2014).
The Australian Government’s Our North, Our Future: White Paper on Developing Northern Australia (2015) identified the Burdekin River as one of nine basins across Northern Australia that has potential for increased irrigated agricultural production. It identified that there was capacity to improve agricultural output in the Burdekin River basin “subject to overriding concerns of sediment and reef water quality management” (Australian Government, 2015b).
CSIRO identified that raising the Burdekin Falls Dam wall could increase capacity by 590,000 megalitres to a total capacity of 2,445,000 megalitres. Other potential dam sites were also noted at Hells Gate and Mount Foxton, however, construction at these sites would reduce inflows to the Burdekin Falls Dam.
Raising the Burdekin Falls Dam wall and constructing new in-stream and off-stream storages throughout the catchment could support an additional 1000 km² of irrigated agriculture (Gallant, et al., 2014), (Commonwealth of Australia, 2014) – 100 km² in the Lower Burdekin, about 500 km² along the Elliot Main Channel to Bowen and potentially more than 400 km² along the Bowen River, upper Burdekin River and possibly Belyando–Suttor sub-catchments (Gallant, et al., 2014).
However the Burdekin WQIP has highlighted that an expansion of irrigated agriculture could potentially lead to a detrimental increase in nitrogen loads and herbicides and undo achievements made since Reef Plan 2009 initiatives. Any decision to expand water supply infrastructure and agriculture would need to consider:
- that captured water must be allocable and not already earmarked for other users and the environment;
- direct impacts on the land cleared for agriculture and inundated environments; and
- downstream impacts on the receiving waters and environments, including the internationally listed Ramsar wetland and the World Heritage-listed GBR.
While options for hard infrastructure exist, the Queensland Government has identified that growth in agricultural water demand in our region should first be met through soft methods such as improving water use efficiency, trading water allocations (particularly water entitlements not being fully used), and accessing uncommitted water held by SunWater (Department of Energy and Water Supply, 2014).
Water trading occurs in the supplemented areas of the Lower Burdekin below the Burdekin Falls Dam, and is managed under the WRP and ROP. There is currently an assessment underway to determine the viability for water trading in the unsupplemented reaches of the Burdekin catchment above the Burdekin Falls Dam. The intent is that demand for water would first be sought through this process before any release from the General Reserve identified in the table in the Water Use and Allocation section.
With longer, drier periods predicted as a result of climate change (Moise, et al., 2015), more efficient and productive use of our existing land and of water resources would provide a sustainable and strategic regional approach, and reduce the need to increase water infrastructure and alter water flow regimes.