The Environment Agency said flood defences prevented more properties from being affected
A newly-opened flood defence system in a Cornish village performed well despite some properties being flooded, the Environment Agency says.
Six properties in Boscastle suffered flooding as drains became blocked during storms early on Thursday.
Local businesses said that their suggestions in preventing floods were ignored by officials.
The Environment Agency said that about a dozen properties would have been inundated without the £10m defences.
During the storms, tons of debris were washed down hills in the village, blocking newly-installed drains and forcing water to continue down, flooding the affected properties.
Agency staff cleared tons of debris from the new culverts.
Local businesses said flood defence planners had not taken their suggestions on board.
Peter Templar of the The Riverside Hotel said: "I was knee-deep in water in the centre of the road.
"I hold the Environment Agency... responsible.
"They totally ignored our warnings last year when we had ideas of what could be done to avert the situation."
Nearby shop owner Rob Lloyd added: "The camber of the road should have been titled in the opposite direction and a pump installed at the bridge.
"That would have sent all of the water down the left-hand side of the bridge and none of the shops would have been flooded at all."
The Environment Agency agreed that surface water remained a problem.
Blocked drains contributed to the problems in Boscastle
Andrew Houghton of the agency said: "We've probably protected 10 or 15 properties that would have otherwise flooded from water from the River Jordan.
"The properties were flooded by surface water run-off.
"I appreciate that that was an existing problem, and we need to work with county highways and look at how we can reduce the chance of that happening again in future."
Cornwall County Council's county highways department is responsible for the roads.
The council said: "We are investigating the circumstances of this recent flooding incident to ascertain the exact events that caused the flooding to see if anything can be done."
The flood defences, which were officially opened earlier this month, were built in response to the major flooding the village experienced in August 2004.
About 440m gallons of floodwater poured through the village, ruining buildings and washing vehicles away.