They believe that a Department of Water, Land and Biodiversity Conservation survey of the broader community during the next two weeks will produce negative responses and diminish the importance of wetland replenishment, a vital component of the scheme.

Endorsed at a meeting on Tuesday by about 20 members of the group, the colour advertisement (see page 29), calls for completion of the project to "restore the farmland to its former fresh state, rehydrate and flush the wetlands, supply 15 gigalitres to the Coorong annually and from local trial evidence ... return an extra $3m to the community each year".

A spokesman for the landholders, Peter England, Blackford Merinos, says the complexities of wetland management could be lost in any survey that focuses on the concept of 'drains' simply putting winter water out to sea.

"We believe the survey is on a number of levels – to people within 5 kilometres of the catchment, levy payers and the wider community, from Kingston to Naracoorte, Salt Creek to Tintinara and across to the border," he said.

The BHWCG members are responsible for between 15,000 and 18,000 hectares of land subject to rising salinity levels and winter flooding and about 7000ha of deep swamps and perimeter vegetation on the floodplain.

Mr England says there are also concerns about the 'sunset' clause on the Upper SE Dryland Salinity Act 2002 on December 19 which could prevent further drain construction.

"Completion of the Bald Hill development (along with the Reflows structure and associated floodways) will offer many options for flexible management while directly helping to solve the greater problems of salinity and flooding," he said.

A letter (dated March 4) sent to landholders and the community in the SE from chairman of the Upper South East Program Board, DWLBC, Roger Wickes says the Ehrenberg-Bass Institute at University of Adelaide, an independent market research company, will conduct the telephone survey on behalf of the board: "The Upper SE Program Board has called for research into community perception of the Bald Hill Drain development in the Upper SE of SA. Your participation will provide valuable information and assist the Board in providing advice to the Government about the merits of this development."