The severe weather has caused more subsidence on the A431 at Kelston and the road has been closed between Bitton and Bath today and is not yet known when it will reopen.
Commuters and First Bus services 319 & 332 are being diverted via Keynsham and Saltford.
Last week Bath & North East Somerset Council said its state-of-the-art ground radar technology had determined the scale of the problem near Kelston Park and it had carried out work to stabilise the ground underneath the road by injecting grout. Two-way temporary lights meant the road could be kept open.
But the situation has got worse, with the council saying it had decided to close the road because “public safety is absolutely paramount”.
A spokesman said: “The road will be closed for investigation works after the land underneath the carriageway suffered further subsidence. This is due to the intense run-off of water from adjacent land which runs underneath the ground. Because of the extensive amount of water over recent weeks, this has destabilised the ground underneath the highway.
“The council had carried out emergency works last week by injecting grout underneath the road to stabilise the structure. Although this was successful, there has since been further subsidence underground. To prevent even greater subsidence from traffic movements and in order to conduct further ground radar investigations we have closed the road. The duration will be known later this week.
“This is not a decision we have taken lightly. We understand the impact on people’s journeys. Public safety is absolutely paramount.
“Where possible, we urge people to avoid the area. Diversions are in place. Inbound to Bath via the A431 to Willsbridge, A4175 towards the Hicks Gate roundabout, A4 Keynsham bypass, towards the Globe roundabout, A36 Lower Bristol Road, across Windsor Bridge Road, rejoin A431 at Newbridge Hill. Outbound vice versa.”
Christopher Gallop, who lives in High Street, Bitton, told The Week In that he had flagged up his concerns about the state of the road to the council last October.
He said he told the council that indentations on the road were getting deeper, that the surface was shifting as a result of all the water coming off the top hills, and that he was concerned that it was affecting the wall next to the pavement, the other side of which drops down to Kelston Park.
He said he received a call back to say engineers had inspected the road and wall and that they would monitor the situation.
He said that since then the condition of the road had got a lot worse but that underground investigations were only carried out last week.
Mr Gallop said: “How that road has stayed upright I do not know. My fears have been that a heavily laden cement mixer or a school bus loaded with pupils would come off the road.”
