Plans are being submitted to stabilise the slipway at St Catherine's breakwater.
It follows a detailed survey done last year on the damage to the listed landmark by stormy weather.
The surveys by UK-based maritime design specialists AECOM incorporated drones, ground penetrating radar (GPR) and multi-channel analysis of surface waves (MASW).
Immediate repairs to the buttress were then undertaken last autumn.
Now, more intrusive ground investigations are needed on the buttress and slipway to design how best to reinforce them.
Ande Vibert, Public Service Obligations Manager, said:
“Following further surveys and monitoring, the team has determined that intrusive ground investigations, which are only expected to take two weeks, are needed in both the buttress and slipway to better understand their stability and inform the design to reinforce them.
"We know how well-loved St Catherine's is for walkers, swimmers, sailors, and ice-cream lovers alike and we are committed to preserving this historic structure so that it can continue to be enjoyed.”
If permission is given, Ports of Jersey says work will start at the end of October.

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