A special inquiry is to examine how a city centre underpass became flooded below 20 feet of water, trapping motorists.
A Stormont committee met in special session yesterday to quiz civil servants on how torrential weekend rain caused chaos in Northern Ireland.
Officials revealed a team of consultants will now establish how cars became trapped in a multi-million pound underpass built on Belfast’s Westlink which disappeared below floodwaters on Saturday.
The city centre route which links the province’s motorways only reopened yesterday after downpours flooded homes and caused traffic chaos.
Representatives of the Northern Ireland Road Service said they had received weather warnings on Friday on the eve of the downpours. By Saturday they had 200 staff and 100 vehicles on the ground when 122 roads were closed — 12 of which still remain under water today.
But Ulster Unionist Assembly member Fred Cobain, who chaired the special sitting of the Committee for Regional Development, said the response to the floods was poorly organised.
Something went seriously wrong
Mr Cobain claimed it was local politicians who co-ordinated activity to help families with flooded homes in parts of Belfast.
“This is the third flooding difficulty we have had in three years. This isn't the first. I would look over it if it was the first and we were learning. But, I mean, we have had three of these,” he said.
But Water Service officials insisted their own investigations were already under way and they announced plans for a full independent inquiry.
“I will be appointing a firm of independent consultants to carry out an investigation on our behalf,” said Road Service chief executive Geoff Allister.
“These will be consultants who have not been involved in any way with the work to date on the (underpass) contract.
“And the sorts of things I want them to look at will be the whole background, intensity of the rainfall, to establish clearly the cause of the flooding, to look at the design and to look at the construction standards.”
He said the conclusions of the inquiry would be used to help avoid a recurrence of the flooding.
DUP Assembly member Jim Wells said lives could have been lost if the flooding had happened at night. And he expressed concerns that five cars, including one with a trapped driver, became caught in the flooded underpass.
He asked why drivers had not been diverted away from trouble.
“People were allowed to drive into that situation. Right up until the water was two metres high and nobody stopped them. Something went seriously wrong.”
Mr Allister said the road had been closed with the assistance of police and could not explain how drivers accessed the flooded route.
Mr Allister confirmed that in the building of the underpass a decision had been made to change the design to allow for a rerouting of the Clowney River but said early indications suggested it had not contributed to the flood.
Committee members spent two hours questioning Mr Allister, as well as officials from Northern Ireland Water and the Rivers Agency. Politicians raised serious concerns over what they said was the lack of a co-ordinated response. But officials said that a single phone number allowing the public to seek help from all appropriate agencies in the event of a flood should be ready to go into operation by the end of October.
The Rivers Agency said that despite anecdotal evidence of increased flooding, this was not borne out by statistics and said Northern Ireland had suffered less flooding than the Republic and UK. Rivers Agency operations director Philip Mehaffey said that dumping into waterways was contributing to unexpected floods, with discarded rubbish blocking overflow grilles a persistent problem. Mr Mehaffey said he was first warned to expect Saturday's heavy rainfall in an initial alert received on Thursday. He said: “The warnings got firmed up and got more horrific as time went on.”