Was riding around Birmingham today and saw, in the old brick bridges crossing the canals, an archway, about a foot above the ground, around 2 feet tall and that stretched back around 12_
-18 feet. There’s an entrance to each ‘hole’ but no exit, and cant think what they were for. Any ideas?

PIctures?

Possibly a space for flood gates?/Damns locks at a gues sbut I would need a pic

These?

they were for your punting pole to be placed on a bridge so you can get some purchase [ actually I always assumed that I dont know it to be fact ]

Can you google a pic that shows what you mean?

Have a look at the edge of the cannal and there may well be two groves one each side,about 6 inches wide, the inhabitants of the holes are planks which in the event of a breach on the canal and to save water are taken out of the holes and slotted into the groves across the canal, most have been removed now probably due to vandalism

I’d have thought that those were actually temporary works holes in the arch to hold the formwork and the scaffolding which then lost their infill and have gradually degraded.

Were the little tunnels for drainage behind the arches?

As for JY’s pic, on some bridges you’ll see a horizontal line of protruding stones just below the curve of the arch. I believe they were for centering or scaffolding. See pics of the Ribblehead Viaduct and the Pont du Gard for examples. The holes in the canal bridge might have a similar use.

Would go along with the punting pole theory.

Are you talking about big enough holes for a person? Sort of like the refuges you get in train tunnels for worker to avoid oncoming trains?

Probably made by rodents of unusual size.

I’d go for drainage of some kind. Storage of wooden poles or stop logs in a tunnel would have resulted in them rotting; better to put them on a rack in the open air.

Could be a drain from the road above, now redundant, but more likely to drain the bridge abutment – the wall has to take the soil pressure, but better not to give it water pressure as well.

But a photo would help, I may not have visualised the thing correctly

Storage for the stop planks as project says.

I dont think they exist 😉

This is a nice bridge where you can see it is offset and it has a weird pattern on the inside of the brickwork – cannot find a good photo on internet

Was it like this one?

I guess like others dam board storage.

Machine gun nest? Door in one side of bridge bricked up gun ports on the other?

JY – look up ‘skew bridge’ on wiki.

Could it just be a void built in to save on the amount of bricks used?

My bet is storage for damming boards; since canals narrow at bridges they were often dammed under bridges for maintenance and repairs. Sometimes you can see slots in the walls.

Aaah, are you sure they are actually holes? Could have been a sticker 😉

Aaah, are you sure they are actually holes? Could have been a sticker

A sticker would look like a crack, not a hole in the wall! 😆

I can’t help with the original question, but spursn17’s question reminded me of this bridge in Worcester, which I think is worth a picture in its own right.

Holes in brick bridge are for the arch support wood work whilst bridge was being built. Pretty common practice, though on Stone bridges there would often be blocks protruding just below the arch.

Would be interested to see a picture of the OPs holes (oo er).

I doubt they were punting holes, they legged narrow boats through narrow tunnels.

I think that they’re Jack arches, try googling images for it.