Serious questions are being asked about Brighton and Hove City Council’s management of seafront safety after papers show councillors had been made aware of major deficiencies last year.

Structural engineers have been working on the seafront’s historic arches after a section of it collapsed while workmen carried out repairs at a pub.

Earth and rock fell into the Fortune of War pub in the Kings Road Arches after a worker removed a piece of plywood at the back of the building, causing the road above it to sag.

The A259 eastbound remained closed at the weekend between West Street and Ship Street following Friday’s collapse as engineers carried out emergency work to stabilise the road and started an investigation into why it collapsed.

Despite four days of work, the council remains unable to confirm the extent of the problem and still has no idea how long the main road will remain closed.

But now questions are being asked about why the council failed to reinforce the road after a council report from November 2013 identified that sections of the arches had become “structurally defective”.

The report was presented to the council’s policy and resource committee as part of the contractual arrangements for strengthening the Kings Road Arches.

Another report written earlier in the year warned that parts of the seafront were reaching the end of their serviceable life.

It examined about 375 different structures and assets worth about £300 million along the seafront.

Councillors were told the vast majority of the structures are more than 120 years old and large sections of these are “at the end of their serviceable life.”

The report reads: “The reconstruction, strengthening and refurbishment of Kings Road Arches (numbers 36-61) between Alfresco’s Restaurant and the West Pier form part of this overall programme. Following recent surveys these arches have been found to be structurally defective.”

Warren Morgan, pictured below, Labour leader on the council, said the Green leadership had failed to invest in much-needed construction work despite knowing it was desperately needed.

He said: “The collapse of the structure under the A259 seafront road near the junction with West Street shows how critical the condition of our most important transport arteries is.

“It is vital for business, tourism and of course traffic and major disruption will do immense harm to our city’s economy.

“I believe that despite knowing that the city’s main seafront road and the arches below it are in need of tens of millions of pounds of investment, the council’s Green leadership has chosen to spend money on a series of other traffic and transport projects it has deemed more important and more in line with their political priorities. This has to end now.”

Brighton and Hove City Council is the lead custodian of the seafront, which involves both the maintenance of the historic infrastructure and development of key and iconic sites.

About five million people travel along the seafront every year and it is a key part of the city’s visitor economy.

In the 2013 report it was identified that not all parts of the area had received the investment needed to allow them to keep up with changing demand.

Under the Highways Act the council has a duty to ensure that highways are adequately maintained and as part of that work it must ensure that supporting structures are safe for use and fit for purpose.

The council’s report reads: “The heritage structures and infrastructure managed by the council along the seafront require significant investment.

“Not all existing assets have received the investment needed to meet the changing patterns and demands of usage.

“The arches, which house many of the seafront businesses, are intrinsic to the seafront’s commercial success and are part of the structural support for the city’s major highway the A259 road and footways.

"Many of the structures require significant refurbishment and are under constant monitoring.

“Madeira Terraces is another current example, where extensive additional financing and resources are needed to meet the refurbishment needs identified.”

Among the work that has been identified as being crucial for the seafront’s future is an arch repair programme, which is expected to be delivered over ten years and the commissioning of structural surveys in areas like Madeira Terrace and other structures.

In the past few months a new scrutiny panel on seafront infrastructure has been established to work with the local community and business groups to identify the main challenges for the ageing structures and establish the best ways to move forward.

The panel, headed by Labour’s Gill Mitchell, was warned last month that the council could face a repair bill of about £80 million. This includes at least £65 million for the arches, £10 million for retaining walls and £5 million for railings.

To pay for repair and restructuring works, councils are urged to put aside 1% of asset values – £3 million in Brighton and Hove’s case.

Councillors were also warned the authority could struggle to meet the increasing financial demands with a general government grant, which currently provides £78 million to the council, which could be cut to £2 million by 2020.

And last month, Leon Bellis, a senior engineer at the council, told the scrutiny panel that the current infrastructure required serious investment or the seafront could be forced to close.

He said: “We have a programme to address the situation but it needs a commitment and funding.

“The £3 million would only allow us to catch up to where we should be and allow us to programme in future works.

“We’ll do what we can to maintain the situation with the resources we have. We could be in a situation where the seafront slowly closes down, which no one wants.”

Adam Chinery, 44, the chairman of Brighton and Hove Seafront Businesses Association, said: “The council needs to give us information about whether the collapse at the Fortune of War was an isolated incident or if it was related to the bigger issue of structural weakness in the infrastructure of the arches that we already know about.

“I don’t understand why there seems to be such a massive lack of money available to deal with this problem.”

Laurence Hill, manager at the Fortune of War pub said the incident has affected business over the weekend with 30% of the pub being closed.

But other business owners at the arches said the collapse had not caused any concern. Mike Levy, owner of Castor and Pollux, said he was not worried about business.

And Aurelia Antkowiack, 25, manager at Coalition, added: “If the weather was good at the weekend then the collapse probably would have affected business, but I don’t think it was too bad and I really don’t think it will affect our future business.”

Coun Morgan said the recent collapse highlighted that the council had to carry out urgent surveys in the immediate area to check the stability of the road before further collapses occurred.

He said: “The council needs to urgently re-survey all of the arches in the vicinity of the Fortune of War to check the possibility of more collapses.

“Questions have to be asked as to how this was allowed to happen with no clear funding stream to address the problem.

“It is inconceivable that the Green administration were not warned about the state of the seafront structures when they took office and they should have made it a priority from day one.

“We are now in a situation where the A259 seafront road is collapsing and there is no identified funding to address the problem.”

Conservative group leader Geoffrey Theobald said the council should have seen the warning signs coming that the area may have been unsafe with some businesses having already closed down due to the same problem.

He said: “I’m very surprised that the problem hasn’t been picked up before given how many times this road has been closed for work by the various utilities and the fact that the nearby Riptide gym had to be shut down recently for just this reason.

“The council now needs to get this resolved as quickly as possible as we approach the busy summer season.

“We’ve just been awarded our highest ever allocation of Local Transport Plan funding from the Government and I’ve been saying for a while that more of this should be going on basic road maintenance.

“The income that the council will get from the i360 development, which we supported, will also help a great deal. It is not glamorous work but the coast road is vital to the continued success of the local economy.”

But Green councillor Ian Davey defended his party’s management of the seafront and accused coun Morgan of calling for money to be spent that the council does not have.

He said: “Currently there’s no evidence to suggest that the cause of the problem on the seafront is anything other than historic alterations to premises in the arches.

“Councillor Morgan voted for our spending plans in March, when we committed £2.6 million to the seafront in addition to the £2.2 million that was spent last year.

“This exceeds anything spent on the seafront when Labour were in charge and presided over a major collapse by the carousel.

“Unlike Coun Morgan we know we can only spend money that we have.

“He’s calling for us to divert money that we’re close to securing from central government for Valley Gardens in 2015. We don’t have it now, and it’s not ours to spend on anything else. If we were to try, it would be taken away from the city altogether.”

Brighton and Hove City Council has so far been unable to announce how long road closures will stay in place or how long it will take engineers to examine and fix the problem, but it is understood the work could last for weeks.

A council spokesman said: “Structural engineers have been working all day on a detailed evaluation of the site.

“They are now working on a plan of action that will specify what needs to be done and how long this is likely to take.

“We hope to be able to let residents know on Tuesday how long we think the disruption is likely to continue for.”