The public is being urged not to swim in, enter, or walk around the Victoria Marine Lake at West Park under any circumstances following a serious incident.
On 21 June, a child was pulled through an opening in the seawall at Victoria Marine Lake.
The child was swept out to sea but was rescued and taken to the Emergency Department. They were later discharged with minor injuries.
Infrastructure & Environment says the incident highlighted the dangers caused by the seawall's deteriorating condition.
Since then, more warning signs have been installed, and the government is considering other safety measures, including additional physical barriers and engineering work.
Infrastructure Minister Deputy Jonathan Renouf says they are taking the safety issue seriously.
“We are extremely fortunate that this serious incident did not result in a tragedy.
"While the child involved thankfully escaped with minor injuries, under different circumstances, the outcome could have been far more serious, and potentially fatal.
"The safety of Islanders and visitors is our first and immediate priority.
"We are reinforcing existing safety warnings and urgently assessing further measures to reduce the risks posed by the current condition of the Marine Lake.
"I am asking everyone to follow the safety advice and stay out of the Marine Lake at West Park while this work is undertaken.
"Engineers are now assessing options to address the immediate risks and develop longer-term solutions for the site.”
The Horseshoe-shaped seawater bathing pool opened in 1897 to mark Queen Victoria's Diamond Jubilee.

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