NOT one drop of water savings has been delivered to the Snowy River from the $29 million Murrumbidgee Barren Box swamp project since NSW water-sharing plans were suspended in 2006.

The Murrumbidgee Irrigation corporation built a levee across the swamp in 2005-06 to cut its evaporation losses by 30,400 megalitres a year.

Murrumbidgee irrigators sold 20,000 megalitres of the saved water for $29 million to the NSW, Victorian and Federal governments' joint enterprise, Water for Rivers, which was charged with reviving the Snowy and Murray rivers' environmental flows.

Yet the Snowy Water Savings Entitlement Register shows the Barren Box project delivered nothing to the Snowy or Murray rivers in 2007-08 or 2008-09.

Meanwhile, Murrumbidgee irrigators gained high-security allocations of more than 90 per cent in both seasons as well as some general security water.

This season, just 46,700 megalitres will flow down the Snowy River, 38,000 megalitres of which has come from allocations made against water entitlements held in the Murray, Goulburn and Murrumbidgee irrigation systems.

Snowy River Alliance lobbyists say they are shocked that Barren Box, one of the most secure sources of water for the Snowy River, was delivering nothing.

"They're ripping off the Snowy," Alliance vice-chairwoman Louise Crisp said.

However, one of the architects of the project, Murrumbidgee Irrigation chairman Dick Thompson, said the zero allocation simply reflected the suspension of water-sharing plans in the midst of a drought in November 2006.

But Mr Thompson admitted MI received 150,000 megalitres of conveyance water last season, which is the type of water the Barren Box Swamp project saved.

Murrumbidgee Irrigation even has 20,000 megalitres for sale on the temporary market this season, which it has transferred across to a Murray River licence.

Ms Crisp said she wondered whether the NSW Government had been able to "get away" with delivering nothing on the Barren Box entitlement in return for turning a blind eye on Victoria borrowing water savings from the Central Goulburn irrigation 1-4 modernisation works, earmarked for the Snowy, for Melbourne.

A NSW Office of Water spokeswoman said the Government's priority was balancing the needs of the community with the needs of the environment, when making allocations.

"The extreme drought conditions across the southern Murray-Darling Basin have forced the suspension of the environmental flows and environmental allocations in water sharing plans across southern NSW," the spokeswoman said.

"Without this vital step, many communities would have been critically impacted."

Despite the severe drought and record low allocations, NSW managed to contribute 50,000 megalitres of water savings in 2008-09 to the Snowy and Murray rivers for the environment.