A LONG-running saga over the future of a historic railway tunnel has taken another dramatic turn.

In the latest twist, Bradford Council has announced planning rules may have been breached by the Department for Transport (DfT).

A council engineer was sent to the tunnel to make an emergency assessment of its condition.

It follows a recent development when the DfT, which owns the site, began emergency measures to stabilise an air shaft in the face of its “increasingly deteriorating condition” caused by an influx of water.

The work has thrown the reopening of the tunnel into doubt, with Highways England – which looks after the structure on behalf of the DfT – admitting the safety procedures will make it “more challenging” to bring it back into use.

Campaigners are pressing for the 1.4-mile-long tunnel to be reopened to form the centrepiece of a cycle path network connecting Halifax to Bradford and Keighley and have been fighting moves by Highways England to fill in the Victorian structure.

They claim the emergency measures go too far and do not need to be implemented.

Now council leader Councillor Susan Hinchcliffe has asked Secretary of State Grant Shapps to urgently intervene in what the council believes are unauthorised actions.

In the letter, Councillor Hinchcliffe asks for an immediate halt to attempts to fill and seal a shaft at the tunnel and for an independent third party evaluation to assess its condition and use of emergency powers.

She has requested that Highways England withdraws a planning application to seal other shafts at the tunnel, and that representatives of the DfT visit Bradford and the site to discuss funding options.

Bradford Council says the latest action follows efforts taken by the authority recently, including sending an urgent hand-delivered letter to Highways England saying the correct planning process hadn’t been followed. A second letter was sent demanding an immediate halt to works.

The current planning application from Highways England to fill and seal the tunnel has met with more than 4,000 objections and is one of the most commented on applications Bradford Council has ever processed.

Councillor Hinchcliffe said: “Campaigners for the tunnel have been brilliant and we are all backing them.

“The actions of Highways England, which have happened without warning, have put the whole project in jeopardy.

“We need them to halt all the works and withdraw the planning application to seal the tunnel.”

The council’s backing is welcomed by the Queensbury Tunnel Society.

Its leader, Norah McWilliam, added: “Highways England has abused emergency powers and must be held accountable for its actions.

“Intervention by the Secretary of State for Transport is long-overdue.”

But Highways England said its decision to act “had not been taken lightly”.

A spokesman added: “The highest level of legal advice has been taken. The infilling of the shaft in this manner means that any reopening is going to be more challenging, however it could be reversed if an alternative owner came forward to reopen the tunnel. In the meantime, our priority is completing the emergency work to ensure both the safety of those communities living close by and the workforce which needs to maintain it.” Highways England says the tunnel has received the highest risk ranking since September 2013.

To view the plan search19/02242/MAF at planning.bradford.gov.uk.