Strathspey Railway

Question of making very limited budgets stretch as far as possible taking note of risks associated with asset failure. I used to work for an organisation that had literally thousands of bridges, all inspected under a strict regime but when it came to deciding where the repair/maintenance money was spent that decision was reached using other matrix like risk of injury if asset failed, disruption caused if asset failed (not an exhaustive list - far from it).

 

…tends to accelerate bankruptcy.

But more generally, I’m in the camp that doubts much can or will be done. It’s a major structure in a challenging location, which serves a limited purpose.

Scour is difficult to observe, and can lead to sudden collapse (see Glanrhyd for an example). The combination of alluvial rock, fast currents, and tidal waters will be difficult to address; dealing with such long girder lengths would stretch any local authority.

I suspect a number of authorities which have adopted structures will be looking very closely at the liabilities associated with them, and considering just how little residual life remains in them. I doubt this will be the last trackbed cycle trail or footpath to be closed.

 

Oh absolutely, that's the case everywhere, if it wasn't, civil engineering asset management would be a lot simpler and I probably wouldn't have a job! But from a purely selfish point of view, if the recommended interventions have been put on backlog due to money, I'm covered as an engineer, it's a finance problem!

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Another short (1m 55s) video appears to provide an explanation of the collapse: Spey Bridge Viaduct Collapse - 14th December 2025 - Best Viewed From Above

 

Where, if I may ask? The video does not appear to include a sound-track.

It does clearly show the missing pier (of the pair in the middle), but one can sort of see that in the images in the BBC story. As I mentioned, though, it's not clear if that was the initiating event, or a consequence, during the failure.

Noel

 

Noel, I am not a civil engineer or engineer of any sort but it seems to me that, taken with the previous video showing the deep water and the likely river currents, that the sequence was started with a scouring of one of the piers which has subsequently failed. That has then led to the bridge sections collapsing into the river. I interpret the marking on the top of the surviving pier (1m 11s et seq) as evidence that the span nearer the bow girder slipped as the surviving pier moved and the twisted span simply toppled and fell over. I am more than happy for a qualified bridge engineer to correct my speculations!

 

BBC News - Replacing collapsed bridge 'nigh on impossible' cost for council
https://www.bbc.co.uk/news/articles/c4g45p10z3wo

Updated article on BBC today. Confirmed Scour as cause of collapse.

 

I was thinking about this failure, and it struck me that the age of that bridge (built in 1886) might be indirectly related to the failure. Indirectly, because it might not have been corrosion or anything direct; rather, that far back, they probably didn't have the technology to anchor the pier superstructure very soundly to the ground underneath. (E.g. bore a really deep hole, lower a very long girder into it, and leave enough sticking up to build the pier superstructure around top end of the girder.) One could probably render scour irrelevant with an approach like that.

Noel

 

I think you'll find that a certain IK Brunel was very competent in this area.

 

I am no engineer, but I've enough awareness of geology and the power of water to know that this isn't always possible, or fully effective. The Spey is braided, changing channel frequently, and depositing large lumps of rock as the bed. It's also fast, and prone to spate at times. That leaves the bridge footings in not very strong rock, and with protection that varies. If anything, I'm more impressed that the bridge has survived as long as it has before nature found a way of demonstrating our impotence against real forces.