Tuesday 04 March 2014
The Environment Department can confirm the coastal wall at Vazon, Grande Mare, was breached this morning during the 10m tide at 08:33. The 5m high wall collapsed across a width of 7.5m. A section of the car park behind the wall was also lost measuring approximately10m x 3m and approximately 3m deep.
States Property Services engineers were on site throughout the day to organise works for a temporary repair to protect the wall from further damage. Large boulders averaging 3 tons were used to create the base of rock armour protection and crushed granite was used to fill the void behind the wall. Further rock armour will be brought in from Ronez and from the Environment Department's store over the next day or two.
A 5m length of damage near the base of the wall was reported to the Department by a member of the public yesterday afternoon. Environment Department staff and States Property Services engineers visited the site during the afternoon but due to the already high state of the tide it was not possible to affect a temporary repair yesterday. The Department advised the Police, Civil Defence Volunteers and the Castel Constables of the damage to the wall yesterday evening.
The precise cause of the failure cannot be confirmed but this is an old section of granite wall which is rubble filled and backed by a sand dune. It is most likely that the extended period of storms since mid December, combined with exceptionally high tides have taken their toll. The Department cannot, at this stage, comment on whether the over-pumping from La Grande Mare in the last few weeks contributed to the wall's failure.
The Department will be assessing the costs for the reconstruction of the wall and any necessary construction to strengthen the defence in conjunction with States Property Services engineers over the next few weeks. At this stage it is considered unlikely that the coast road will need to be closed for an extended period.
Coastal damage was also reported yesterday at Perelle where stonemasons have today been repairing the seaward side of the wall around the battery (opposite Perelle Hotel). Damage to the slipway will be repaired as soon as tides allow.
L'Eree sea wall also incurred damage with coping stones moved during the high tides. Repairs here will be undertaken as soon as costs can be confirmed.
A further update on coastal defences will be issued on Friday 7 March.
ENDS
