MDBA report finds higher than average water losses


The Murray–Darling Basin Authority (MDBA) has released a report into water losses in the Murray system over the past year with high demand, low inflows, drought and hot conditions leading to higher than average losses.

MBDA head of River Operations Andrew Reynolds said losses were accounted for in ‘conveyance’ water, or the volume of water used to carry water orders to customers.

“Generally losses happen when water evaporates, is used by plants or seeps into the ground,” Mr Reynolds said.

“The past 12 months have been challenging in running the river efficiently with near record low inflows across the River Murray system.

“Drought and sustained hot conditions across southern Australia, as well as the need to make water available when and where it is needed, have all impacted on losses this water year.

“Water losses so far this current water year are 665 gigalitres and are projected to be between 850 gigalitres and 1,000 gigalitres by the end of May.

“While losses in 2017-18 totalled 554 gigalitres, it is more useful to compare the current water year with other years that had similar conditions such as 2015-16, when losses were 849 gigalitres.

Mr Reynolds said water losses for 2018-19 were in part because of the higher river flows over spring and summer to improve storage volumes in Lake Victoria to meet peak demands.

“Transfers to Lake Victoria had not been made earlier in anticipation of some inflows during winter that unfortunately did not eventuate.”

He said the MDBA channelled water through the Barmah-Millewa Forest, due to low inflows from both NSW and Victoria, to meet high demand and to support flows to Lake Victoria.

Mr Reynolds said the conditions had affected allocations for entitlement holders, which are set by the state water authorities.

“The factors affecting water availability is the lack of inflows across the Basin and the significant differences in inflows between Victoria and New South Wales,” he said.

“Inflows in Victoria are around 50 per cent higher than those experienced by drought-hit NSW, meaning Victoria has a greater share of the available water.

“In 2015-16, when conditions were similar to this year, NSW started the year with more water in reserve and available for irrigators.”

The full report is available here