Residents raise alarm bells after Sydney Harbour waterway turns brown

Construction work on one of Sydney’s largest infrastructure projects is being blamed for sending a torrent of clay-coloured stormwater run-off into Sydney Harbour.

A photo of the run off event

There are fears construction work on one of Sydney’s largest infrastructure projects has sent a torrent of clay-coloured stormwater run-off into a popular Sydney Harbour waterway.

The NSW Environment Protection Authority has launched an investigation after Willoughby Bay at Cammeray was turned murky brown on Thursday.

The incident was reported by residents who fear the discolouration could be traced to run-off from Cammeray Golf Course which has been transformed into a construction site for the Western Harbour Tunnel and Warringah Fwy upgrade.

The golf course is located about 600m from the waterway and contains a creek which flows directly into Willoughby Bay.

The EPA has not yet been able to confirm the exact source of the discolouration but in a statement said an investigation into the incident was continuing.

Residents fear the run-off can be traced to construction work at Cammeray Golf Club.

A Transport for NSW spokeswoman said water discharges from the construction site “could have contributed to the run-off in the Middle Harbour catchment” during intense rainfall on Wednesday night.

“Water run-off from the site does not contain any toxic materials or construction waste,” she said.

“The health and safety of our workers, the public and the environment is our priority and we are committed to building the Warringah Freeway Upgrade in a way that effectively manages the potential for erosion and run-off.

“The Middle Harbour catchment receives stormwater run-off from a large area and it is common for stormwater run-off to produce ‘muddy’ water conditions during high intensity rainfall events.”

The incident follows a previous run-off event in October last year that was also believed to be traced to construction activity at the golf course.

At the time, a Transport for NSW spokesman said: “When you have unprecedented rainfall like there are going to be times when sediment is released” but stressed “we are certain the (stormwater) is not contaminated”.

Cammeray Golf Club

Paul Walter, who chairs the local Bay Precinct community group, said the removal of more than 600 trees at the golf course during construction work on the Western Harbour Tunnel could be contributing to the run-off.

“There’s a concern about construction management protocols because if there’s large scale sediment being washed off the site that’s a serious problem,” he said.

A creek from the golf course flows into Willoughby Bay.

“Because the trees have been removed, they’ve removed the ground cover which is able to hold stormwater (within the soil).”

Another resident – who asked not to be named – believes sediment flowing into the waterway could be having an impact on wildlife.

“The golf club is now so exposed and it’s basically an open drain down to Willoughby Bay,” she said.

“The colour isn’t just regular dirt – this is clay coloured and baby poo coloured and the whole bay looks the same now because it dissipates further into the harbour.

“One of the big issues is the lack of information provided to residents. People are waking up and seeing the bay turn brown and we aren’t told why.”