Dredge Bridges - Lochy Bridge and Bridge of Oich

Today, I came across the picture above of the road bridge across the River Lochy at Fort William, the one which carries the 'Road to the Isles' (A830) west to Mallaig. It's not the present bridge, obviously, but I sort of had it in my mind that the previous bridge here had been a suspension bridge. There was nothing for it: I had to research the history of the bridges at this spot. So here it is in reverse order.

The present bridge was built in 1968 and replaced the one pictured above. It was built in 1928, designed by Sir Owen Williams. I'd heard that name before and thought it might have been him who designed the two distinctive bow shaped bridges from the same era on Rannoch Moor (you know - these ones). But according to this article these weren't actually by Williams although he was responsible for a number of road bridges in Scotland, mostly on the A9 and mostly now by-passed (see here).

The 1928 Lochy Bridge replaced a suspension bridge built in 1849 pictured below: this was the first bridge across the river here and, as you can see, its towers were retained in the second, 1928 bridge (although just for decoration as the deck of the 1928 bridge was supported by piers on the riverbed rather than suspended from wires running between the towers).

Lochy Bridge 1849-1928 looking west. Picture credit Aberdeen University Archive

Now I called the 1849 bridge a suspension bridge but strictly speaking it's not, it's a taper suspension bridge. According to the Wikipedia entry for them, they:

differ from the conventional suspension bridge design in that they effectively function as a double cantilever bridge. Each opposing cantilever system is self-supporting. The cantilever half-deck structure of each cantilever is suspended from angled chains, which hang from a tapered main attached to the top of the tower and to the outer end of the half-deck. The main chain taper is achieved by incrementally reducing the number of links stacked across the chain's width as it moves farther from the support tower.

No, I don't understand that either. Maybe it just means it's sort of half cantilever (like the Forth Bridge) and half suspension? Anyway, taper suspension bridges were also called Dredge bridges after their inventor James Dredge who patented the idea in 1836. Their advantage was that they were cheaper and quicker to build. Lochy Bridge cost £1,790 (about £200,000 in today's money), paid for by the local landowner Cameron of Lochiel. That was considerably cheaper than the lowest offer received to build a traditional stone bridge which was £8,000 (about £900k today). The Dredge bridge also took just five months (August to December 1849) to build.

Although a road had been built from Fort William to Arisaig by the Highland Roads and Bridges Commission in 1805-1808, no bridge over the River Lochy was provided at that time and travellers had to continue to use a ferry across the river. A newspaper report of the building of the 1849 Dredge bridge to replace it referred to the ferry as "well and attentively managed" but nevertheless a "plague of careful shepherds and a cause of dread to nervous travellers".

To anyone who has had occasion to cross the river in the old ferry-boat, even in a calm fine dry day, it was unnecessary to say that there was loss of time and much inconvenience experienced; but in a dark wet Lochaber night how very much were all the disagreeables of the ferry increased? The ferry has this day given place to the bridge, and Lochiel has thereby conferred, not on his tenantry merely, but on the public at large an important boon.    

So said Sheriff Fraser at a dinner to celebrate the opening of the bridge held at Robertson's Hotel at Banavie on 20 December 1849. Sadly, Lochiel's health prevented him from being there but James Dredge was: he had supervised the work personally and the sheriff praised him for having paid for cakes and oranges for the 400 local schoolchildren who had turned out on opening day.

But wait a minute - was Lochiel actually as generous as he'd been cracked up to be? The 1875 Ordnance Survey 6 inch map (below) shows a toll gate on the bridge. Does that mean Lochiel had merely fronted the price of the bridge but was expecting to get it back from his dutiful tenants and shepherds over time through tolls? I don't know but no toll gate is marked on the 2nd edition of the 6 inch map surveyed in 1899 (here) so perhaps the price had been paid off by then.

National Libraries of Scotland 

 

There's nothing left to see of the Dredge bridge at Inverlochy but you can still see another one not far away. It's at Bridge of Oich where the A82 crosses the River Oich as it debouches from Loch Oich at Aberchalder just north of Invergarry.

Bridge of Oich from the east. Picture credit: Shawn With the pediments above the arches, I wonder if Dredge was consciously evoking the Georgian architecture of nearby Fort Augustus in contrast to the medieval architecture of Inverlochy Castle he'd sought to evoke with the decorative battlements on the towers at Lochy Bridge?

The Bridge of Oich was built a year after Lochy Bridge, in 1850 (not 1854 as its Historic Scotland and Wikipedia entries say). It replaced a traditional stone bridge which had been washed away in a storm in 1849. (The same storm carried away half of the bridge over the River Oich at Fort Augustus, the rest of which is still standing today (see here), and the whole of the 17th century seven arch bridge across the River Ness at Inverness (see here)). The Bridge of Oich took three months to complete and cost just £620 although it was much shorter than the Lochy Bridge (145 feet (45 metres) as against 240 feet (75m)). Dredge had also stipulated that he would be able to use free of charge the stone from the fallen Bridge of Oich his was to replace.

Dredge also gave a two year guarantee on the Bridge of Oich meaning he would rebuild it at his own cost if it was damaged from any cause within that period except lightning, earthquake or civil commotion. I'm not sure if he gave a similar guarantee at Inverlochy but it was brave of him to do so at Aberchalder because three bridges at this spot had been washed away by floods in the last 35 years. And it's a testament to Dredge's design and workmanship that his guarantee was never called upon and the Bridge of Oich is still standing today. It was bypassed by a new road bridge 100 metres up stream in 1932 (see here and here) but was left as a footbridge. By the 1990s it had fallen into disrepair but was restored by Historic Scotland in 1995-97 and today is a Category A listed building. You can go for a virtual walk across it here.

I leave you with a photo of an interpretation board at Bridge of Oich explaining the Dredge design. (It looks far more cantilever than suspension to me but what do I know ...?)

This board also has the error that the bridge was opened in 1854 but contemporary news reports are quite clear that it was built and opened in 1850. Picture credit Adam Fagen