From tomorrow (18 April), work will begin to shore up a collapsing quarry face in the Vale.
Building the barrier at L'Epine will allow the minor lane next to it to reopen.
The road was closed without warning last June because it was considered dangerous.
The Vale Constables were told by Guernsey Water that the barrier, or 'bund' is a sizeable structure.
The stone will be brought in by tractor, so parking in the access road will be suspended on weekdays.
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States defends decision to put Guernsey beauty spot cafe up for tender
Guernsey's government is releasing more details about the Fermain Café agreement, following a public backlash and petition to keep the current tenant in place.
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The Association of Guernsey Charities wants islanders to understand the consequences of losing their services, as the sector faces challenges.
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Guernsey's Animal Shelter is looking after a large black beetle after a local family ordered a toy online and found a surprise in it.