Outer Harbor shipping channel dredging safer to dump at sea and cost up to $72m to put on land

DUMPING waste soil on land as part of a planned expansion of the Outer Harbor shipping channel could cost up to $72 million and create far greater environmental risks than offloading it at sea, an engineering report has found.

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DUMPING waste soil on land as part of a planned expansion of the Outer Harbor shipping channel could cost up to $72 million and create far greater environmental risks than offloading it at sea, an engineering report has found.

The Advertiser yesterday revealed Planning Minister Stephan Knoll approved a controversial plan to widen the channel, and allow the waste to be dumped 30km offshore from North Haven.

Flinders Ports, which owns and operates the existing site, argues it’s critical to ensure that increasingly large cruise and container vessels are able to arrive and offload in SA.

The ocean dumping site has been selected as it was already spoiled by waste from dredging in 2005 which killed an estimated 2000ha of sea grass.

CONCERNED: Port Adelaide Mayor Gary Johanson, left, SA Blue Crabpot Fishers Association President Karen Holder and Port Adelaide Environment Protection Group Secretary, Tony Bazeley, all oppose the plan. Picture: DYLAN COKER

Prior to the state election, the former Labor government demanded analysis of whether the new waste could instead be dumped somewhere on land.

A report by consultancy firm Arup, published by the state’s Environment Protection Authority, examined the possibility of piping it onto land near Gillman.

The projected cost was between $33 million and $72 million, and noted environmental concerns.

“The risk of blockage is assessed as low likelihood, but with significant consequences should any blockage eventuate, as it would likely occur within a sensitive marine environment,” the report states.

“Subject to the location of any blockage, heavy plant and equipment access is likely to be required which may include clearance of access tracks and lay-down areas for plant.” The Government says it is expected no more than 250ha of sea grass will be lost, and marine life will be unaffected.

Opponents have declared the approval “tragic” and “devastating”, with concerns that mistakes of the past will be repeated in the new expansion.

Port Adelaide Residents Environment Protection Group president Tony Bazeley said it was “particularly tragic” as water quality of the Port River was “coming back” after years of pollution.

“It’s unfortunate this operation is going to set it back,” Mr Bazeley said. Flinders Ports aims to start expansion next year.