Wild weather erodes eastern beaches
Image: Photo: Edwin Monk
In the wake of the wild weather that lashed Sydney in the past week, fears of coastal erosion have arisen at Sydney’s most famous eastern suburbs beaches.
While torrential rain and severe thunderstorms moved through NSW causing chaos across the state, the Bureau of Meteorology issued severe weather warnings for heavy surf and coastal erosion around Sydney beaches.
Professor Ian Turner of the UNSW Water Research Laboratory said “one particular weather event cannot be attributed to any specific factor”.
“In a changing climate we can expect these types of extreme events to occur more frequently. As sea levels rise, we can anticipate that all the Sydney beaches will progressively erode landward,” he said.
Professor Turner said coastal erosion is a serious concern for eastern suburbs beaches, with last week’s weather likely to have contributed further to coastal erosion.
Bondi Beach is already among the most vulnerable and susceptible to coastal erosion, where it is feared a sea level rise of 20 centimetres, combined with a one-in-fifty year storm, would erode much of Sydney’s most famous stretch of sand.
“It is presently thought that for every 10 centimetres in sea level rise, the beach is expected to retreat by the order of five to 10 metres landward. So a one to two metre sea level rise would equate to around 50 metres [of] beach recession,” said Professor Turner.
Waves off Bondi Beach peaked around four to six metres during and following the peak of last week’s storm.
Waverley Councillor Dominic Wy Kanak said rising sea levels had been taken into account by Council.
“A rise of 0.5 metres by 2100 had been assumed by planning authorities including Waverley Council, but the increased rate of warming and ice melting in Greenland and the Antartic make that estimate look conservative,” he said.
“Certainly there will be a lot less beach width (sand area) and we will see the ocean reaching the Bondi promenade walls more often and possibly undermining them in future storms.”
Director of Bondi Surf Bathers’ Life Saving Club, Michael Gencher said treacherous conditions were the primary concern.
“Obviously from a lifesaver’s point of view, the biggest issue was the dangerous conditions causing erosion and creating dangerous conditions for surfers and swimmers,” he said.
Mr Gencher said beach erosion is a serious concern for all beaches, especially at Bondi’s “southern corner”.
“There is always a rip in that corner, and that presents a challenge for us as lifesavers,” he said.
Professor Turner explained the most practical solution to prevent the effects of coastal erosion is “beach nourishment – the periodic placement of extra sand on the beach”.
Mr Gencher said “if we want to preserve Bondi for the beach that it is … it is time that we think of a plan”
He added that last week’s thunderstorm “certainly didn’t feel like summer”.
Conditions at Bondi Beach and along Sydney’s coastline are again likely to be treacherous over the coming week.
