Families evacuated when a massive section of river wall buckled and collapsed in a town centre may not be able to return home for days.

Three businesses are also boarded up and roads closed as agencies in Bridgwater work to evaluate the damage and restore the wall behind which run gas, water and electricity supplies, and sewers.

Around 40 metres of flood defence wall along the River Parrett on West Quay and part of the road collapsed after torrential rain hit the town on Friday afternoon.

Firefighters from Devon & Somerset Fire & Rescue, and officers from Avon and Somerset police cordoned off the area. Roads surrounding the area – including West Quay, East Quay, Fore Street, part of Eastover, Castle Street and the town bridge – were closed.

Adrian Fraser, 48, who runs West Quay Records saw the drama unfold opposite his music shop. He said: “I had been serving a customer and was just putting the money in the till when a friend, Steve, shouted ‘oh my God’. I went over to the door and it was like something out of a disaster movie. The wall was just crumbling, as though there was an earthquake.”

His shop is one of three which, though undamaged is boarded up . “I feel so sorry for the new baby shop next door. They were just due to open, and then this happens. It’s like watching the Berlin Wall come down.”

More than 20 people living in the area were evacuated, first to the town’s arts centre. Most are with friends or family but some have gone to the YMCA.

The old riverside wall was extended some years ago by the Environment Agency to improve the town’s flood defences. The wall also supports the highway which is the responsibility of Somerset County Council. Sedgemoor District Council, Somerset County Council and the Environment Agency are working together to resolve the problem.

In a joint statement at the weekend they said: “There are two phases, firstly to stabilise the material behind the failing wall. This is being progressed with urgency by the three authorities. This will be followed by the “permanent” solution, which is the reconstruction of this flood defence wall. It is clear the collapsing wall has caused considerable disruption and will continue to do so for an extended period.

“The wall has been displaced outwards five metres from its original line for a length of 20-30m. Underground services have been significantly damaged or disrupted with several pipelines severed or damaged. The highway surfacing is significantly unstable with parts of it lost.”