Although plans for the Bakerloo line extension have been paused for the moment, the route is to be protected from future development.

That will ensure any future developments along the route can’t be permitted if they would in some way – usually foundations — impact the Bakerloo line later on.

Guidance now published by the Department for Transport has outlined the rules that local councils should follow to safeguard the route.

Along with the tunnels themselves, other areas covered by the safeguarding regulations include:

• New stations at Elephant & Castle, Old Kent Road (two stations), New Cross Gate and Lewisham;
• A new shaft at a site off Lewisham Way at Alexandra Cottages, between New Cross Gate and Lewisham station;
• Train stabling to be provided at a site off Wearside Road south of Lewisham town centre; and

The use of a site at New Cross Gate as a primary worksite (as well as for a new station) and the use of a site in the Old Kent Road as a secondary worksite (as well as for a new station).

Although the rules don’t prevent developments, the councils and TfL have the right to refuse any planning permission which could affect the Bakerloo line extension if, or when, it is built in the future. If a council wants to grant planning permission to a development, that TfL objects to, then the Secretary of State gets the final say on the decision.

It’s not unusual for safeguarding rules to be imposed even on delayed or uncertain projects. Crossrail had safeguarding rules in place for several decades, and Crossrail 2 also has similar rules covering developments along its planned routes.

In fact, the safeguarding rules can encourage early construction of some sites, such as a ventilation shaft under a Moorgate office block built a decade before Crossrail was given approval, and the Nova office block in Victoria includes a basement corridor for Crossrail 2 to use as a link to the tube station. Both were added as the safeguarding rules meant that the council and developers were fairly sure where such facilities would be needed at some point in the future.