An emergency sandbag operation in Devon failed to kick in because villagers were unaware of flooding until the main street was underwater, an investigation into failed defences will be told.
The Environment Agency's new £1.2 million scheme to protect Braunton failed its first test after the River Caen burst its banks just before Christmas, leaving homes and businesses sodden.
However, a separate project, a voluntary local plan to distribute about 100 sandbags to help shore up defences, was not activated because river levels surged during the night and no out-of-hours alert system was in place.
Officials from the Environment Agency (EA), North Devon Council, Braunton Parish Council and other organisations will meet tomorrow to review the plan and see how it can work in the future. Parish Council clerk Tracey Weaver said the plan needed to be "updated".
She added: "We were not able to activate the plan because we didn't know about the flood until 7.30am – by that time water was already flowing down the street.
"We didn't have any indication – everyone thought the flood defence was going to hold and when it did flood it was in the early hours and nobody was prepared."
The EA scheme, which was completed in the summer, was designed to reduce the risk of flooding from a one-in-20 chance in any one year to a one-in-100 chance.
But after record levels of rainfall the river broke its banks on December 22, leaving 30 business and 12 homes flooded .
Agency spokesman Mike Dunning said the local plan was not its responsibility, adding: "There is no substitute for local knowledge."