Some drains in parts of Belfast are so badly blocked with dirt and concrete they are barely visible, despite a Roads Service cleaning drive to prevent a repeat of June's floods.
And the city's Lord Mayor has said that if the Department for Regional Development is incapable of keeping drains free, local councils may have to do the job.
Last week the Belfast Telegraph inspected drains on Hatton Drive, close to some of the areas worst-hit by the flash floods.
More than half the drains we observed were either substantially or completely blocked.
When made aware of the issue, Roads Service said it had dispatched a team to solve the problem.
Resident Audrey Harvey said the drains had been blocked for several years.
"I've lived here for 25 years - it's years and years since I saw anyone out to clean drains here," she said.
Hamilton Rice, also from Hatton Drive, said he had not seen the drains being cleaned for many years.
"The drainage system needs to be cleaned the whole way through," he said.
"They replaced the heavy old cast iron grille covers with ones that are easy to open.
"I've watched children as young as four opening drains and putting Coke cans, wood and bricks in.
"There's also concrete being poured down drains which leaves them partially free, but when a flood comes they can't cope."
Mr Rice served in the Royal Navy and frequently visited tropical countries as a seaman.
He said systems for coping with monsoon rainfall in other countries were very effective.
"I visited Malaya, Singapore, Manila - all of these places had storm gullies because the monsoons come all the time," he said.
"The systems they have out there cope with far heavier rainfall than we experienced in June."
Lord Mayor Jim Rodgers said blocked drains were an issue that needs to be urgently addressed.
"I firmly believe the flooding would not have been anywhere near as severe if the drains had been functioning properly.
"It's certainly possible that the city council could do a better job than is being done at present, but we would need additional funds if that was the case.
"The minister needs to look at this issue and treat it with the seriousness it deserves - I understand there are a very small number of these cleaning vehicles in Belfast.
"This is something that maybe should be looked at by the Review of Public Administration."
A Roads Service spokeswoman said: "Roads Service has attempted to gain access to Hatton Drive on a number of occasions in order to carry out routine gully emptying, but has been unsuccessful due to the presence of parked cars and the narrow width of carriageway available with these parked cars."
She said a gully emptier was dispatched to the street earlier this week and a squad would clean by hand those areas that cannot be accessed by the vehicle.