Some resurfacing work may have to be redone

David Ward, regional director of the Highways Agency, said the problems occurred because the asphalt was not rolled and compacted sufficiently to keep the water out.

If the work needs to be done again, it could cause more traffic disruption.

Alison Birkett of the Automobile Association said: "It does seem to be one chaos after another on the bridge.

"It only opened earlier this year and motorists have already endured five years of congestion and repairs, so it does seem to be double the pain for the road user."

An accident during previous refurbishment work on the bridge resulted in the deaths of four workmen.

The four welders fell 80 feet from a gantry on the bridge in September 1999 in high winds.

Triple glazing

Two firms were fined last month after pleading guilty to offences under the Health and Safety at Work Act 1974 related to the incident.

Major repair work started on the bridge in 1995, and should have been completed by 1998, but was delayed when the structure was found to be in worse condition than expected.

Nearby residents in Avonmouth had to put with noise and dust during the five years of work.

Avonmouth councillor Pat Roberts said: "They are talking about working at night, but what about the people who live underneath the bridge, you can't have that row going all on all night."

Local resident Ronald Hall, who lives near the bridge, said: "Even though they have given us triple glazing, it was still noisy."

Highway engineers will inspect the damaged road to monitor the situation and determine if further work needs to be done.