BURDEKIN DRY TROPICS NATURAL RESOURCE MANAGEMENT PLAN 2016-2026
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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 on page 58. for these wetlands to continue to provide the services so important to the GBR is limited, and now many of these areas act as permanently inundated conduits for bulk water supply and runoff from sugarcane farms.
Three irrigation districts exist in the Lower Burdekin subcatchment:
• BHWSS;
• Lower Burdekin Water Northern Divisions( previously North Burdekin Water Board); and
• Lower Burdekin Water Southern Divisions( previously South Burdekin Water Board).
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.
Lower Burdekin catchment ground and surface water interaction issues
The Lower Burdekin is the largest floodplain system on the Australian east coast. It has a diverse assemblage of coastal ecosystems, including one the greatest concentrations of wetlands situated in the GBR catchment. Given the magnitude of its physical, biogeochemical and biological process functions, it is an important functional component of the overall catchment of the GBR, and provides a host of ecological functions and processes for the GBRWHA( Great Barrier Reef Marine Park Authority, 2013).
However, these high value wetlands within the Lower Burdekin in and adjacent to the Ramsar wetlands of Bowling Green Bay are significantly impacted upon by changes in the landscape, particularly those changes associated with hydrological processes and pollutant inputs( Davis, et al., 2016)( O’ Brien, et al., 2016). Consequently, the capacity
BHWSS is operated by SunWater and is upstream and on the north-west bank of the Burdekin River. Lower Burdekin Water operates downstream towards the coast in the Burdekin River Delta and supplies and manages the uplift of groundwater.
The main matters of concern – including the effects of seawater intrusion, a rising groundwater table, and increasing concentrations of salts – relate to the health of the Burdekin River Delta aquifer and coastal wetland ecosystems. There is increasing urgency to mitigate these issues, because adverse impacts on crop productivity, hydrology, habitat quality, and downstream ecosystem function are becoming more evident. Contributing factors include the amount of water being released through watercourses and channels for irrigation access, deep drainage and channel leakage, and irrigation practices( Milla, 2013).
Changes to the landscape and the oversupply of supplemented water through irrigation delivery / channel systems have led to the loss of seasonality in the coastal wetland ecosystems flowing into the GBR. Relatively high ground water levels and perennial surface flows have resulted in a loss of natural water detention, fish passage and nursery habitat, productive native pastures and biogeochemical cycling. One of the
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