At a glance
Online availability of flow data and water resources information has increased substantially since 2011, including:
- various state-based data portals
- a national repository with flow and other data for more than 3400 sites
- a national set of 222 long-term, high-quality reference flow gauging stations
- monthly updates of rainfall patterns and streamflow status
- regional information on the state and trends of streamflow, groundwater and major water balance components.
Surface and groundwater conditions have varied considerably since 2011, largely in response to climate. National water storage levels varied from above 80 per cent to below 50 per cent during the period. State-level variations in storage have ranged from above 75 per cent to below 45 per cent for New South Wales and Tasmania, whereas South Australia’s water storage has remained constant at between 80 and 100 per cent, supported by water from the Murray River. Following dry conditions in the northern and southern extremities of the Murray–Darling Basin since 2012, Basin rainfall during the 18 months leading up to 2016 was largely in the median range. Basin streamflows in early 2016 were mostly around average in southern and central areas, with a mix of above average and below average flows in the north. The South West Coast was one of the few wetter-than-normal areas of Australia leading into 2016, with 55 mm of total rainfall in January 2016; this was 224 per cent higher than the 1980–2015 average. Conversely, total rainfall across the Carpentaria Coast division was 98 mm, 52 per cent lower than the 35-year average.
This 2016 report includes a new assessment of the state of groundwater, based on national aggregated information. Groundwater condition is mostly graded as poor across Australia’s drainage divisions, reflecting historical groundwater use, significant numbers of bores and low knowledge of the impacts on groundwater-dependent ecosystems. Trends were mostly assessed as deteriorating or stable.
Unlike the extensive site-based assessment of the SoE 2011 report, water quality assessment for 2016 was based on a range of sources at the state, region or river scale. At a regional level, Lake Eyre Basin water quality monitoring, for example, revealed results generally consistent with previous reporting, the period sampled and the hydrological conditions. Some improving trends were noted for the Murray–Darling Basin, but no assessment was possible for more remote areas, including the South Western Plateau, North Western Plateau and Pilbara–Gascoyne drainage divisions.
Finally, the state and trends of ecological processes and key species populations ranged from very poor, with deteriorating trends across the Murray–Darling, to poor to good condition, with stable trends for south-eastern and south-western regions, to good for much of the rest of the country.
The pressures discussed previously influence the state and trends of inland water environments in multiple ways, and the pressure–state interactions are further affected in many areas of the country by our management responses. Climate and land use largely control much of the state of both surface-water and groundwater resources, and these are further modified by water resources infrastructure and operational management. Pests and invasive species then interact with the groundwater and surface-water hydrological regimes to influence the state of inland water environments.
Australia’s surface-water and groundwater conditions have varied considerably during the past 5 years, largely in response to the varying climatic conditions mentioned previously. In 2012, after the strong 2010–12 La Niña event, many regions of the country had experienced recent high streamflows and floods, groundwater levels were stable or rising, and Australia’s aggregated water storage holdings were around or above 80 per cent of capacity. After the millennium drought, this wetting of the country was welcome, with positive responses for water quality and ecological processes. More recently, with the pressures of historically warm years and significant regional drying, the condition of our inland water environments has been more varied.
Four condition assessments of Australia’s inland waters are provided in this report, considering the state and trends of:
- inland water flows and levels
- groundwater resources—a new assessment for 2016
- inland water quality, focusing primarily on surface water
- ecological processes and species populations.
The 2011 state and trends assessments were based, to a greater degree, on analyses undertaken specifically for SoE 2011, including a highly detailed site-based report for water quality. For 2016, the assessments are based on publicly available data and information, including state-based SoE assessments, and specific national or regional assessments, such as for the Great Barrier Reef catchments, the Lake Eyre Basin and the Murray–Darling Basin.
One of the challenges of assessing states and trends is determining the baseline against which the assessment is made. For this report, SoE 2011 provides the baseline, although there is some uncertainty about the methods that were used to reach a particular grade. The Wentworth Group of Concerned Scientists has been leading work since 2008 to provide more comprehensive and uniform baselines and assessments of environmental condition (see information on environmental economic accounting in the Drivers report). Under the National Plan for Environmental Information, the Bureau of Meteorology published a Guide to environmental accounting in Australia (BoM 2013b), which describes water accounts and their purpose, the risks and issues to be considered in accounts, and pathways for implementing accounts. Additionally, the Australian Bureau of Statistics has published annual economic-focused environmental accounts since 2014. Such approaches offer future opportunities, including aligning data with current assessment methodologies and increasing the use of readily available monitoring data.