Burdekin
Climate and water overview
Climate
Rainfall
Rainfall across the Burdekin region was below to very much below average for the 2013–14 year (Figure C1). The total area-averaged rainfall over the region during the year was 485 mm, which is well below the long-term area-averaged rainfall of 656 mm (based on the 1900–2014 period). Consequently, flows in the major rivers within the region were much lower than the long-term average (see Streamflow responses).
Figure C1 Annual rainfall deciles for the Burdekin region during the 2013–14 year
Annual rainfall ranged from more than 900 mm in the north of the region, to less than 200 mm in the central inland parts of the region (Figure C2).
Figure C2 Total annual rainfall for the Burdekin region during the 2013-14 year
Rainfall for 2013/14 ranged from 300 mm in the central parts to more than 900 mm in the north east, (Figure C2). Across this region and relative to the long-term rainfall totals, rainfall ranged between very much below average in the central parts to average in the north and south west. There were no strong influences from large-scale climate drivers during the year. Conditions in the Pacific Ocean were neutral and a short-lived negative Indian Ocean Dipole event, which developed towards the end of last year, decayed at the start of the 2013–14 year. The El Niño-Southern Oscillation Index was also neutral for most of the year.
Figure C3 shows that the Burdekin region experienced well below-average rainfall for most of the wet season (October–April). The below average rainfall during the wet season contributed to well below long-term average flows in the major rivers within the region (see Streamflow responses).
Figure C3 Total monthly rainfall for the Burdekin region during the 2013–14 year compared with the long-term average and percentiles for the region
Evapotranspiration
Potential evapotranspiration across the Burdekin region was generally average to above average for the 2013–14 year (Figure C4).
Figure C4 Annual evapotranspiration deciles for the Burdekin region during the 2013-14 year
The potential evapotranspiration estimate was produced by the Australian Water Resources Assessment system landscape model (AWRA-L) version 3.0 (Van Dijk 2010). The AWRA-L model uses a modified version of the Penman–Monteith method to produce the potential evaporation. Daily AWRA-L potential evaporation grids were produced based on daily gridded climate data that were available on a 0.050 (approximately 5 km) national grid.
The total area-averaged potential evapotranspiration over the Burdekin region during the 2013–14 year was 1,485 mm, which is similar to the long-term area-averaged potential evapotranspiration of 1,489 mm (based on the 1970–2014 period). Potential evapotranspiration was highest in the north along the coast and relatively uniform across the remainder of the region (Figure C5).
Figure C5 Total annual evapotranspiration for the Burdekin region during the 2013-14 year
Soil Moisture
Figure C6 shows that soil moisture was generally below average in the Burdekin region during the 2013–14 year (compared against the 1970–2014 period). The soil moisture is based on a simple conceptual representation of soil water storage and transfer processes averaged over a 5 km x 5 km grid cell derived from the Australian Water Resources Assessment system landscape model (AWRA-L) version 3.0. The model produces a soil moisture grid for the region at a daily time step, which is then averaged over the entire year to produce an annual soil moisture grid. The annual grid represents the mean daily volume of soil moisture across the region during the year.
Figure C6 Annual soil moisture deciles for the Burdekin region during the 2013-14 year
The combination of below average rainfall and soil moisture conditions across the Burdekin region has contributed to the well below average streamflow in the primary rivers of the Burdekin region during the 2013–14 year (see Streamflow responses).
Streamflow responses
Significant water events
There were no significant water events in the region during the 2013–14 year.
Streamflow
There are four primary river systems within the Burdekin region:
- Bowen–Broken
- Burdekin
- Cape
- Suttor–Belyando.
More detail on these river systems, including location, is provided in the Surface water section of the 'Contextual information'.
Total annual flows in these rivers during the 2013–14 year were well below the mean annual flow. River flow in the northern part of the region (Burdekin and Cape rivers) was approximately 40–50% of the mean annual flow; flow in the southern part of the region (Bowen–Broken and Suttor–Belyando rivers) was less than 20% of the mean annual flow.
The 3–month period between January-March is usually when the majority of the total annual flow occurs in these rivers. Total flow during this period was well below the long-term average (figures C10–C13), which contributed to the overall below average annual flow during the 2013–14 year. Cape River, in particular, was very dry; flow was only observed for three months of the year (February–April).
The flow conditions in the four primary rivers generally reflect the below average rainfall conditions experienced across the region during the year (see Climate). The above average rainfall in November 2013 and February 2014 did not result in above average streamflows in these rivers, presumably because soil water stores and groundwater levels were relatively low following very dry periods during the year.
Figure C7 Total monthly flow along the Bowen River during the 2013–14 year compared with the long-term average and percentiles for the river
Figure C8 Total monthly flow along the Burdekin River during the 2013–14 year compared with the long-term average and percentiles for the river
Figure C9 Total monthly flow along the Cape River during the 2013–14 year compared with the long-term average and percentiles for the river
Figure C10 Total monthly flow along the Suttor River during the 2013–14 year compared with the long-term average and percentiles for the river
Major water reforms
Water Supply (Safety and Reliability) Act 2008 amendment
The amendment to the Water Supply (Safety and Reliability) Act 2008 will transform the regulation of water and sewerage service providers in Queensland. The focus of regulation is now on outcomes, and the new framework will provide greater transparency and accountability for customers about their services.
Under the new framework, service providers will no longer need to have:
- strategic asset management plans
- system leakage management plans
- drought management plans
- outdoor water use conservation plans.
Instead, drinking water and sewerage service providers will need to prepare an annual report on their performance against key performance indicators that have been developed in consultation with the industry and will be set by a notice from the Queensland Water Supply Regulator. As part of the new framework, the Department of Energy and Water Supply will prepare an annual comparative report that compares the performance of water and sewerage service providers across the entire state.