In an era of rising sea levels and increasingly severe weather events, a robust, long-term solution was required to safeguard the railway and the town of Dawlish in Devon. BAM was awarded the contract by Network Rail to complete the 415m second phase of the sea wall, including improvements at Dawlish station, a new Colonnade Viaduct pedestrian bridge over Dawlish Water, and the spillway carrying the river to the beach.
The location between the railway and the sea was a particular challenge, with access through a 2.4m clearance underpass and 3-4-hour tidal windows with high ranges. The innovative approach developed by BAM and designer Tony Gee used lessons learned from Phase 1. An eight-legged, jack-up barge called a WaveWalker was used to walk along the seabed installing piles.
The scheme used bespoke low carbon concrete to reinforce the sea wall, reducing carbon by two thirds. The project team worked with the community, holding regular town and beach litter picks, responding quickly to any concerns from local people, and sharing popular progress videos, some with more than 1.5m views.
Beyond flood protection, the project provides full accessibility to the seafront and the new sea wall, while acknowledging the history of the town through design details.
This project was recently shortlisted for the Civil Engineer awards.