Directory : Water Directory 2013
PAGE 68 Water Directory 2013 Environmental Flows The concept of environmental flows or provisions was formally introduced in 1994 when the Council of Australian Governments (COAG) developed a Water Reform Framework requiring State, Territory and Commonwealth Governments to give priority to determining allocations or entitlements to water, including the environment. The National Water Initiative (NWI) further required the states and territories to establish specific water management plans for balancing environmental water needs with the consumptive use of water by the broader community. In 2008--2009, the total amount of water released by water providers for environmental purposes was 722GL, more than three-quarters (77%) of which comes from the water supply industry. At the national level, there was a 28% decrease in the volume of water released for specific environmental purposes between 2004--2005 (1,005GL) and 2008--2009 (722GL). The overall decrease in environmental flows was attributed to drought-related reductions in total water availability, particularly in Victoria (environmental flow decrease of 289GL or 77%) and Queensland (decrease of 234GL or 61%), situations which in both states have changed considerably over the recent period and since early 2011. Key Commonwealth, State and Territory water agencies recognise two forms of water used for Environmental Flows: • Planned (rules-based) environmental water relates to statutory requirements to maintain specifc water regimes (e.g. particular levels, flow rates, aquifer pressures). • Held (entitlement-based) environmental water relates to specifc entitlements, which accrue annual allocations of water that can be extracted (or left in-stream) for environmental purposes. It is apparent that some water utilities do not measure all Environmental Flows and there is subsequent uncertainty around the level estimates. In previous years, environmental flows were not separately identified in the physical supply and use tables: nor was there clarity in regard to supply, distribution, and use by the various industries. The latest ABS data (2010--2011) concedes a high degree of uncertainty within its survey information for the current period. However, an eclectic mix of more qualitative data from other agencies provides a more descriptive example of the benefits of changes to environmental flows. Frog monitoring is providing important information on the way wetlands respond to floods and environmental flows in the Murray River system. The NSW Office of Environment and Heritage (OEH), the environmental water manager of NSW, has completed ongoing frog monitoring of the mid-Murray and several associated creeks and the Lower Murray systems since 2009--2010. In 2010--2011 and 2011--2012, 11 frog species were identified across the system compared to the eight species detected during initial surveys conducted in 2009--2010. Many other benefits from the recent 2010--2011 and 2011--2012 high system flows have been observed including large waterbird breeding events, fish movement and recruitment, improved health of river red gums (Eucalyptus camaldulensis) and aquatic vegetation and frog recruitment.
Water Directory 2014