DUBLIN'S most famous bridge is still in need of serious structural repair one year after Dublin City Council closed off a section to fix faulty pillars, according to heritage experts.

Remedial works were carried out on the stonework of O'Connell Bridge at the end of last summer after large numbers of stress cracks and a missing section of parapet were discovered.

Part of the roadway was closed off to allow the repairs to take place and council officials insisted the job was completed.

However, one year on the National Conservation and Heritage Group (NCHG), which highlighted the initial problems, said there are still significant problems on the east side of the structure.

"Throughout the bridge there are granite stones held up with little pillars," explained the NCHG's Damien Cassidy. "In this particular instance after we drew attention to it, the council came down and replaced about 12 and left the rest of them."

However, Cassidy claimed that while extensive work appeared to take place on the bridge, some parts were left untouched and problems remain.

"They held up the bridge for about two weeks but I don't know what they were doing," he said.

"They left dozens [of pillars] unfixed. To be fair, they fixed the ones on the western side but on the eastern side they haven't touched them and they need to."

Cassidy explained that 'spinning' pillars, not properly connected to the structure, pose a serious threat, particularly to boats passing underneath the bridge.

The NCHG has previously warned that rising water levels, due to global warming, could cause serious damage to bridges on the Liffey if water smashes off the top of the structure as opposed to passing underneath.

A spokesman for Dublin City Council said that the bridge was "structurally sound" and its condition was the subject of constant review.

He said that while a report on required maintenance work has been forwarded to the National Roads Authority (NRA) for consideration, there was no immediate concern.

"We do constant maintenance and we review it and it's definitely structurally sound," he said.

He denied that the bollards were moving.

"What we do as well as part of the maintenance to any of the bridges is check to see what needs to be done. Regarding O'Connell Bridge, [inspectors] did a report and sent it to the NRA."

He added that the two-week repair works on the moving bollards, carried out at the end of last summer, had resulted in a number of them being replaced.