The problem at the A46 Old Decoy Main Drain Bridge wasn’t dramatic in the way that infrastructure failures sometimes are. No sudden collapse, no closed road. Just erosion, quietly doing what erosion does — eating away at the bank beneath the structure, season by season, until the edge of a 4-metre farm access track had been worn back far enough to make it genuinely dangerous.
Farm vehicles were still using the track. That was the concern. The ground supporting the edge of that access route was going, and if it went far enough, a tractor or trailer going over the side of an active drain channel was a realistic outcome rather than a theoretical one. Highways England needed it fixed, and fixed properly.
Civcon took the job on with a one-month programme. Before anything could be dug out, there was a land ownership question to settle — confirming who held responsibility for the ground under the bridge. It’s easy to skip past that kind of step in a project summary, but getting it wrong early causes the sort of delays that compress everything else in the programme. It was sorted before excavation started.
The eroded material was cleared out to give a clean base to work from, and revetment bags were used to rebuild and reinforce the drain’s sides. Revetment is a practical solution for this kind of application — it conforms to the bank profile, handles water pressure without shifting, and cuts off the conditions that allow erosion to continue. The edge of the access track was then reinforced to restore its load-bearing capacity for agricultural vehicles, and steel pins were installed throughout to lock the repair in place against future movement.
Completed inside a month, with farm operations kept running throughout. The bank is stable, the drain is protected, and the access track is back to being exactly what it needs to be — something a loaded farm vehicle can use without a second thought.
