The southern Sydney bay residents say is becoming a mudflat

Travis Read says the bay has about 15 years before it becomes a mudflat. (ABC News: Declan Bowring) Locals in Oyster Bay in Sydney's Sutherland Shire say the bay will become a mud flat in 15 years due to sediment build-up. Some residents say the bay has become too shallow to use for recreational boating, leading to vessels becoming trapped. Council has proposed improving stormwater drainage to limit sediment runoff but has rejected dredging the bay. Link copiedShareShare articleFor 12 years, a green waste bin has become a symbol of a Sydney bay that once was home to sailing boats and oyster leases. Year after year, the bin has been slowly disappearing under the mud just metres from the shore at Oyster Bay. Residents in this part of the Sutherland Shire say the bay is filling up with sediment and becoming a shallow mudflat. Locals say the green waste bin has been stranded in the mud for 12 years. (ABC News: Declan Bowring) Oyster Bay local Travis Read said it had been slowly happening since 1970 when the council filled in part of the bay to build a football field and a golf course. "It was only ever about 4 feet, 1.2 metres, deep and now at low tide, it either dries out or it's 10 centimetres deep," said Mr Read, who is president of the Revive Oyster Bay community action group. Sailing boats could be launched and sail around the bay in the 1980s. (Supplied: Revive Oyster Bay and Catchment Community Association) "That changed the shape of the bay, reduced the flushing of the bay and it meant that sediment out of the creek had nowhere to settle before it went into the bay. Oyster Bay in 1961, prior to the construction of a golf course and football field. (Supplied: Sutherland Shire Council/LPMA) Oyster Bay as seen from above in 2025. (Supplied: Sutherland Shire Council/Nearmap) Mr Read said at the current rate, the whole bay would become a mudflat within 15 years. "If we're accumulating even 1cm a year … in 10 to 15 years there's no bay left," he said. A report by Sutherland Shire Council said about 83,000 square metres of sediment had been deposited in the bay since 1980, about 57 per cent of it coming from the upstream catchment. The remainder likely originated from the Georges River. The report suggests sediment has been increasing at about 3mm a year since 1980. Travis Read says at low tide the bay is either dry or 10cm deep. (ABC News: Declan Bowring) Mr Read said the mud had become a navigation hazard. In one instance, the shallow mud once trapped two tour boats carrying children that would have required them to wait until the tide rose again had it not been for quick-thinking residents who evacuated them on longboards. Harry Taylor, who has lived in Oyster Bay since 1957, remembers when the bay was used for oyster farm leases, fishing and recreational boating. Harry Taylor, 93, remembers when the bay was used for recreational boating. (ABC News: Declan Bowring) Mr Taylor said he did not see the bay used for boating or swimming anymore because it had become too muddy and was no longer deep enough. He took his own boat out of the water when the fields were built. Liz Adams says the bay is too shallow for boating. (ABC News: Declan Bowring) Liz Adams, who has lived in the area for 55 years, said she watched boating slowly disappear from the bay after the golf course was built out. "It's just mud everywhere, and you've got to really be at full tide to be able to go anywhere, even in the smallest boat," she said. "It's not really possible to enjoy the bay now." Sutherland Shire Council recently endorsed a plan to use measures such as improving stormwater treatment, stabilising creek banks and constructing bioretention systems to address sediment build-up in Oyster Bay. A spokesperson for the council said their studies did not support a "definitive conclusion" that Oyster Bay would become a mudflat, as the Revive Oyster Bay group has suggested. Council has proposed more than a dozen measures to address sediment runoff. (ABC News: Declan Bowring) "Council understands community concerns about the long-term condition of the bay," the spokesperson said. "These actions are designed to improve water quality, manage erosion, and reduce sediment loads entering the bay from within the LGA [Local Government Area]. The spokesperson said dredging Oyster Bay would not align with the council's policy and would not provide a sustainable or cost-effective solution. "Council's approach is to consider targeted dredging in specific locations, such as upstream creek tributaries and stormwater outlets, where it can deliver clear benefits," the spokesperson said. "Broadscale dredging of the entire bay is not proposed and remains as a NSW government responsibility." However, Mr Read said if the council adopted their plan in full, it would only reduce the inflow of sediment by 5 per cent. "At least what has accumulated since 1980 needs to be removed from the bay," Mr Read said. "Unfortunately,

The southern Sydney bay residents say is becoming a mudflat

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