A row has broken out in Australia over the spiralling cost of Sydney’s US$278m Northside sewage storage tunnel, being constructed by Sydney Water.

A New South Wales government appointed waterways advisory panel, which is probing the scheme, believes Sydney Water may have deliberately underestimated the cost of building the tunnel to be sure of state government support.

The project was originally estimated at US$234m, but current estimates put the overall cost at US$280m.

Sydney Water is tackling this US$46m difference by cutting back on other key parts of the overall project, including a sludge pipeline.

The 15.8km long tunnel is being bored from Lane Cove River to the North Head sewage treatment plant and the deep-ocean outfall at Manly on Sydney’s North Shore. An underground reservoir is also being built to store sewage during heavy rain for later treatment. Completion of the scheme is scheduled for September 2000.

Advisory panel member Bob Wilson, a former Sydney Water Board managing director, said he felt deceived after supporting the tunnel project and associated facilities, including the pipeline, that were later scrapped.

The panel said the soaring cost of the project was diverting cash away from other pollution control schemes. The New South Wales cabinet was expected to consider a draft report from the advisory council in March as T&T International went to press.

Apart from rising costs, the report was also expected to look at settlement problems caused by tunnelling that have led to a 23mm drop in ground levels in the Manly Wharf area. The document was likely to criticise Sydney Water for its lack of accountability and secrecy.