Lane closure update
The A399 at Mockham Down still has one lane closed for safety.
A full survey of this part of the road has now been completed. We are now planning further ground investigations, including drilling boreholes, digging trial pits, and carrying out DPSH tests. These works should take place within the next four weeks commencing 1 June 2026
Once we have the results, we will develop a repair plan and begin construction to rebuild the damaged wall as soon as possible.
The lane closure will stay in place while this work is carried out. More updates will be given when new information is available.
Background
Mockham Down is located along a curved section of the A399 main road near Mockham South in North Devon.
On one side of the road, the ground rises steeply and is covered with vegetation. On the other side, the land drops sharply down into the valley below, which is held up by a stone wall and an earth bank. The wall is about 50 metres long and up to 3 metres high, vegetation covers the wall and much of the slope. This part of the road is also on a sharp bend, which makes it more affected by ground movement and water.
We first looked at the road after cracks were found along the outer edge of the eastbound lane. Parts of the road surface had also started to sink. This was reported by a Devon County Council inspector.
We continued to monitor the area and found that the damage was getting worse, because of this, we closed the eastbound lane so we could safely carry out further checks and to keep road users safe. It reduces the weight of traffic on the damaged edge of the road and helps prevent the problem from getting worse before repairs can be carried out.
What we are doing
We have carried out an initial check of the site. We will now clear plants and vegetation so we can safely access the area. This will allow us to carry out further surveys and tests of the ground.
These checks will help us understand what is causing the cracks and movement in the road. Once we know this, we will decide the best way to fix the problem.
We are aware this is a well-used part of the highway network and a matter of urgency with regards to this project.
Contact us
We understand there are lots of unknowns and concern in this present moment. We apologise for any inconvenience this causes and thank you for your patience.
For any questions or concerns, please contact us at highway.engineeringdesignq-mailbox@devon.gov.uk.