Emergency air-support is being drafted in at Llanbedr to temporarily block the gap in the coastal defence ahead of high tides expected this weekend.
Natural Resources Wales has arranged for a helicopter to lower giant, industrial-sized sandbags into the gap, to take the brunt of the tides, which are predicted to be among the highest of the year.
The work is being carried out with support from Snowdonia National Park Authority which has experience of using helicopters.
The damage was a result of high tides earlier this month, which combined with a strong storm surge, caused flooding and damage to coastal defences across the country.
At Llanbedr, the storm caused a 50 metre breach in the defence, which resulted in five homes, the airfield and more than a thousand acres of agricultural land being flooded twice each day from the incoming tide.
Work to build an access road for repair vehicles to reach the hole in the defence started earlier this month and should be finished by the end of January.
Then work to repair the defence using 15,000 tonnes of boulders, clay and soil will begin.
As a precaution, Natural Resources Wales is taking this emergency action in case this weekend’s tides cause any further damage, and to provide safer, drier conditions for the repairs to take place.
Meanwhile, flood forecasters from Natural Resources Wales are closely monitoring weather forecasts and tide levels along the entire Welsh coast in the run up to the weekend to gauge whether conditions will again combine to create a storm similar to that of earlier this month.
A spokesperson from Natural Resources Wales said:
“We’ll be keeping a very close eye on weather conditions and tidal forecasts over the coming days as the picture becomes clearer.
“It’s important to stress that the high tides alone are not predicted to cause too much of a problem. For similar conditions to what we saw earlier this year to occur, a storm surge would need to perfectly align with the tides – and this is what we are tracking.
“While the work carried out by the helicopter is expected to help, it will not hold back the sea completely, and some sea water is expected to seep through gaps and possibly come over the top. If successful however, it will significantly reduce the amount of flooding in this area during the high tides.
“After the recent coastal flooding, we assessed each of our coastal defences for damage, and will have staff out and about this week checking to make sure they are in good working order for this weekend’s tides.”