The Discovery and Recording of a Victorian Hydro scheme at Orrin Falls, Ross-shire (original) (raw)
by Meryl Marshall (NOSAS)
Aultgowrie, west of Muir of Ord, is a favourite area for short walks and I have been aware of a hydro scheme at Orrin Falls for many years but never given it much thought. However when I was browsing the Fairburn Estate website looking for something else I came across a photograph c1900 (below) and the following comment:
John Stirling used estate workmen to build a turbine house at the Orrin Falls and one further up river under the supervision of Mr Bagot from Glasgow and electric light was installed (in Fairburn House) in 1898.
The hydro-scheme was much older than I had thought and was worthy of more attention! For many years it had been overgrown with rhododendrons and overhung with trees however a few years ago the estate had carried out a programme of clearing these and it was more accessible. The site is marked on the current OS map as “weir” but there was obviously much more to it than that. It was unrecorded on the Local database http://her.highland.gov.uk/ and on the National database https://canmore.org.uk/. So 18 months ago I set about gathering more information.
The Orrin Falls, GR NH 469517, are (or were) a series of attractive waterfalls (see painting above) within a gorge of the River Orrin. The natural rock is conglomerate and the total height drop from top to bottom of the gorge is roughly 15m. The hydro scheme is on the south bank of the gorge and comprises
- A dam
- The remains of an earlier dam
- A lade or channel
- A generator house.
And several other features;
- A rock-cut channel (on the north bank) probably intended as a salmon ladder
- The abutments of a footbridge
The early photograph of the dam circa 1900 – reproduced with the permission of Fairburn Estate
The scheme seems to have gone through several phases before being abandoned probably in 1961 when the flow of water down the river was reduced due to the construction of the Orrin Dam, part of the wider Conon Valley Hydro scheme, in the higher reaches of the river. Nevertheless the Orrin Falls hydro-scheme was revived in the early 1980s and now provides electricity for Fairburn House.
My first task was to survey it and make a sketch. The survey was done by using a combination of compass and pacing with GPS Way Points to confirm (or otherwise) significant points. Once home I “drew-up” the sketch on polyester film using the survey as a template. I have often drawn up sites using a CAD programme (equivalent “Inkscape”) but in many respects I like the end result of a hand drawn plan better, so I decided to go with this. Two years ago Ian Parker of the Survey and Graphics Dept, RCAHMS (now retired), had talked me through his method of hand drawing sites giving me hints and tips along the way, I now feel much more confident.
The next task was to take photographs and details of the features. Drawing the sketch first had enabled me to become very familiar with the place; I had discovered all its little features and the best angles from which to take the photos
The dam is circa 50m in length and crosses the river obliquely from NW to SE. It is constructed of concrete and 3.5m height at its highest. On the downstream side there is sloping concrete buttressing with inclusions of rounded stones. At the north end a fish ladder, a sloping ramp of 1.5m to 2m width, has been damaged by a recent spate (April 2015)
The remains of an earlier dam are seen to the east/downstream side of the present dam. Although ruined, it appears to be of similar construction to the present one; it is probably the one in the c1900 photo.
The dam with the remains of the earlier dam in the foreground
The lade is a concrete “box” channel roughly 50m in length; it is c.2m deep and 1.5m in width. There are three wooden sluices; two at the west end and one at the east end, two metal grids for catching floating debris (the one positioned diagonally is controlled by an overhead hoist) and two overspills, the one at the west end appears to be redundant. The east end of the lade comprises a split channel of two short parallel sections; the S section has a sluice part of which is covered by wooden planking, the N channel appears to be redundant and is blocked off by a concrete wall.
The lade viewed from the east.
The west sluice with metal grid and overhead hoist
The generator house was built in 1926 by Gilbert Gilkes & Co Ltd, Kendal (information from Fairburn Estate) probably on the site of an earlier one. It is constructed of dressed stone, roughly 11m x 5m x 12m high
A rock cut channel on the north bank may be an early fish ladder possibly predating the hydro-scheme; it is at a higher level than is necessary today and roughly 20m in length, 1m in width and 1m deep.
The abutments of a bridge are situated in the middle part of the gorge above a waterfall. The bridge was probably built at the same time as the hydro-scheme to provide access to it. It is in two sections, at a slight angle to one another; the south abutment, (A on the sketch) is constructed of 2 large boulders with infill of concrete and small boulders. The north abutment (C) is a small platform 2m2 with stone faced sides built into the north bank of the river and the middle abutment (B) is a small concrete and stone structure with evidence of old cables and pieces of the wooden deck on top of a rocky knoll on the edge of the gorge.
The central part of the gorge with the abutments A and B seen on either side of the waterfall, the dam can be seen in the distance.
An undated photograph of the bridge (reproduced with the permission of Fairburn Estate)
After this other matters took over and Orrin Falls was forgotten about!!
It wasn’t until 4 weeks ago, with deadlines for submission to the Discovery and Excavation annual publication coming up, that I thought I had better write the report up and submit it to both the databases. Writing up was easy because I had done all the hard work; it was just a matter of putting the data together. But I also needed to contact the landowner for permission to use the old photo c1900. She was most interested and kindly provided me with supplementary information and additional photographs, one of the bridge and one of a Victorian painting (not reproduced here) of the Orrin Falls.
The final stage was submission of the report to the databases. Highland Council HER was easy it was just a case of sending the information by email to Ian Scrivener-Lindley or HER@Highland.gov.uk And incidentally our own Tim Blackie has recently volunteered to help with uploading information submitted by NOSAS members to the database so we have a direct link. As far as Canmore is concerned submitting information was done by filling in the on-line forms for Discovery and Excavation Scotland (the Archaeology Scotland annual publication). Not only will the site appear in the publication but it will also be transferred onto the Canmore website automatically.
Access to the land on which this site is situated is covered by the principles set out in the Scottish Outdoor Access Code. For further information go to www.outdooraccess-scotland.com
TAKE CARE if visiting: the site has many Health and Safety issues – cliffs, deep water, uneven slippery surfaces
Orrin Falls Generator
Orrin falls bridge abutments
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