She said the plan was for it to be in a car park to reduce the impact on the reserve.

“Sydney Water will also improve facilities at Parsley Bay by building a new and improved amenities block on the ground floor of the existing Caretaker’s Cottage,” she said.

The facility is designed to improve harbour and coastal water quality,reduce odours,“and brings the level of treatment of the wastewater collected in the catchment into line with the rest of Sydney”.

But McMahon said community consultation had been “minimal and inefficient”,apart from the aesthetics of the pump station.

She said volunteers were concerned about the loss of biodiversity and green space,with the reserve and beach potentially off limits for years:“I,alongside my Bushcare volunteer members,are intimately familiar with the flora and fauna that will come under threat from the proposed scope of construction works.”

McMahon also said existing water pipes needed to be addressed for public health and safety.

“It’s the existing old infrastructure that tree roots are growing in and sewage overflows from the manholes during high rains,” she said. “Large warning signs make frequent appearances to warn swimmers not to enter.”

Parsley Bay is suitable for swimming most of the time,according to theState of the beaches 2020-2021report,“but may be susceptible to pollution after rain,with several potential sources of faecal contamination including stormwater”.

Sydney Water also faces calls for an independent inquiry following aburst water pipe in Lane Cove earlier this month that left thousands of residents without the ability to flush toilets or use their showers for days.

Planning Minister and Lane Cove MP Anthony Roberts said Sydney Water’s response had been “appalling”.

“It gives me no pleasure at all to say this is the most appalling public response to an issue in my 30 years of public life,” Roberts told Sydney Water managing director Roch Cheroux.

Woollahra Council backs the plan to stop dumping raw sewage into the ocean,a council spokesman said.

“Council staff have been working closely with Sydney Water to minimise impacts on Parsley Bay Reserve,” the spokesman said.

Woollahra Greens councillor Nicola Grieve said stopping raw sewage flowing into the ocean “is long overdue”.

“But the Parsley Bay pump will only fix the sewer into the sea,not the sewer into the Harbour,” she said. “This will require Sydney Water to invest in upgrading century-old pipes and infrastructure.”

Vaucluse Liberal MP Gabrielle Upton said she had taken up residents’ concerns about protecting wildlife during construction.

“I have made it clear to Sydney Water that our community expects it to minimise any environmental impacts while delivering on this important project,” she said.

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