Canberra, Australia --- (METERING.COM) --- July 7, 2010 - Approximately a quarter of Australia’s entitled water on issue is unaccounted for, amounting to an average 5,600 Gl/year, according to a new survey on water interception activities across the country.

The survey, the first of its type, found that the largest interceptions were for forestry plantations (2,000 Gl/yr), followed by farm dams (1,600 Gl/yr), stock and domestic activities (1,100 Gl/yr), and overland/floodplain harvesting (900 Gl/yr). Further in a wet year, the interception volumes are estimated to be even greater, with floodplain harvesting increasing up to 2,600 Gl.

The survey, which was undertaken by Sinclair Knight Merz in partnership with the Bureau of Rural Sciences and CSIRO, was aimed at mapping water interception activities and establishing a baseline for planning and management.

Under the National Water Initiatives state governments are required by 2011 to record all significant water interception activities, which if unchecked could reduce water availability, presenting a risk to the security of water access entitlements and the achievement of environmental objectives for water systems.

The survey report notes that there are major deficiencies in the data and that further studies are required, for example on temporal changes.

The National Water Commission, which commissioned the survey, said it will continue to support targeted investments to improve both the quantification of water use by interception activities, and to encourage the proactive development of planning and regulatory frameworks to address all unaccounted water use.