The Australian Conservation Foundation said it had reached an agreement with the Victorian government's Department of Sustainability and Environment to direct 200 megalitres of water into the Hattah Lakes wetlands in northern Victoria.

The manager of the foundation's Health Ecosystems Program, Paul Sinclair, said that while the federal and state governments were buying back water licences and diverting irrigation water back into the Murray-Darling system, it was taking too long and the group wanted to highlight the urgency of the problem.

"The federal government has been buying some water and returning it to desperately dry wetlands in the Murray-Darling Basin, but it needs to do more,'' Dr Sinclair said.

''Many people are frustrated by the slow pace of action to rescue the basin's wetlands.''

He said the water would be released into the lakes late next month or in early May and would help ease the plight of red gums in the lake system about an hour south-east of Mildura.

Dr Sinclair conceded the water to be diverted into the Hattah Lakes was a tiny amount compared with the 700,000 megalitres the federal government had spent $1.5 billion buying to divert into the river.

But buying water on the market was a way people concerned about the problems of drying wetlands could help and that each $15 contributed would be used to donate 75,000 litres of water.

''More than 90 per cent of wetlands in the Murray-Darling Basin have been lost, mainly because too much water is being taken out for irrigation," Dr Sinclair said.

Today the government will launch a $100 million round of water purchases in the southern Queensland catchment of Lower Balonne, which takes in the controversial cotton farm Cubbie Station.

The round of purchases could pave the way for the government to acquire some or all of the station's massive water entitlement - enough to fill Sydney Harbour - after it went into voluntary administration last year.

This month Cubbie's administrators, who are seeking almost $400 million for the station, rejected three bids for the farm as unacceptable.

The federal government has committed $350 million to buy back water in Queensland and expects interest from a number of water holders in the Lower Balonne. The area has been inundated with rain in the past month, causing flooding.