Network Rail complete £1.8m programme to improve Mallaig Line

Credit: Network Rail

Network Rail has completed a £1.8 million programme of work that will improve the resilience of the railway on the Mallaig line at Lochailort in the West Highlands. Starting in February 2022, the work delivered by Network Rail and supply chain partner QTS followed on from previous activity undertaken at this location in the summer of 2020, when severe weather caused flash floods that washed away 80 metres of railway.

The initial phase of the improvement work involved installing a new concrete drainage tunnel, or culvert, next to the existing Allt na Criche bridge that carries the Allt na Criche burn under the railway. Engineers removed 800 tonnes of material from the existing railway embankment in preparation of the new culvert being installed. The majority of material removed was then recycled on site for other elements of work.

Installation of the 63.3 tonne culvert took place in the spring during a 78-hour period of continuous working. Four, precast culvert sections were installed in ten lifts using a 250-tonne crane to complete the task. The area was then backfilled with 450 tonnes of stone around the culvert to raise it back to track level. The railway embankment was then reinstated before 40 metres of new rail was laid on 200 tonnes of new ballast.

A new Terramesh bund 112 metres in length, up to 2.3 metres in height and 5.3 metres wide at the base was then created to help to protect the railway and surrounding land from future flooding events.

“Our work on the Mallaig line at Lochailort was a significant undertaking, given the sheer size of the culvert and the scale of the excavation involved,” Jeremy Spence, Programme Manager for Network Rail, said. “The successful delivery of the work and the significant benefits this project delivers will help tackle severe weather incidents that are increasingly frequently presenting challenges to the railway industry. By protecting the railway from extreme weather events, we also mitigate the risk of the impact of this for passengers, freight customers and lineside neighbours. I would like to thank our contractor QTS as well as the local community for their patience and support while we delivered this critical improvement to Scotland’s Railway”.

“The work carried out at Lochailort over the last five months has hugely improved the resilience of Scotland’s Railway for years to come,” Andy Steel, Operations Director for QTS, said. “Our team undertook some important work during this period, including the installation of a structure that will help manage waterflow to safeguard the integrity of the railway during heavy rainfall.”