There are many factors why the line to Tavistock cannot accommodate either a double track or a cycle track alongside a single line, despite being a former twin track line.

When the line was first built, I doubt there was much in the way of track & land drainage. There's evidence within the tunnel of some drainage. Within the cuttings, it is proposed drainage runs are installed on both sides of track to prevent flooding. The pipework and catchpits take up considerable space.

Secondly, there was little or no provision for maintenance staff to walk the track in a place of safety while trains run. It is proposed a safe cess walkway will be installed along the entire length of the route.

Additionally the steep rock faces in the cuttings are unprotected. A rockfall would spill onto a twin track railway and could result in derailment and serious injury. To put protective netting along all faces would cost millions. By only reinstating a single track, the alignment can be designed so it lies away from potential rock fall zones, minimising the amount of rock netting required.

It is cheaper for Devon CC to provide a cycleway on an alternative alignment away from the railway than it is to rock-net the whole route. There is however one area where it may run adjacent the track.

The delay to any major engineering scheme is more down to planning and finance rather than technical reasons.