After a small defect turned into a bigger hole, the Department of Infrastructure carried out emergency repairs over the weekend to the Mountain Road.

The repairs included replacing a culvert and relaying the road.

Originally a small surface defect developed in centre of the carriageway just above Guthrie’s Memorial on the Mountain Mile on the A18 Mountain Road, and temporary surface repairs were immediately undertaken, but on Friday it worsened.

A DoI statement said: ‘One of our engineers examined the site and found that a small sink hole was developing. The road was immediately closed to traffic on safety grounds and to allow the road to be excavated and the site investigated.

‘It was found that the old combined stone culvert/clay pipe drainage system that takes water from the high side of the road to the low side had completely collapsed across the centre line of the carriageway.

‘On the Mountain Mile there are more than 130 lateral culverts, each located every 10 to 20 metres.

‘While over the years some of these have been replaced by modern drainage pipes as part of road reconstruction, or specific drainage works , many are still of the old stone built variety. It had been originally hoped that a repair would suffice and the road reopened late on Friday evening.

‘Once the extent of the issue was exposed it was decided it was necessary to fully excavate and replace the old culvert with a new 600mm diameter pipe, together with a new roadside access grid.

‘It was decided to push on with this work over the weekend to ensure that the Mountain could be reopened in time for weekday commercial and commuter traffic.

‘On Saturday, the site was excavated, with stone blinding, 16 metres of drainage pipe and new drain/sump installed. The trench was then capped with concrete, which had to then cure overnight.

‘On Sunday two layers of asphalt were laid, with the site cleared and road reopened to traffic by 2.30pm.

‘We are grateful to our staff (both construction and at the Poortown asphalt plant) and our suppliers (equipment and concrete) who stepped up at little or no notice to come in at the weekend and get this work done as soon as possible.’