Qualla: Shira Hydro-Electric Scheme

Shira Hydro-Electric Scheme: Introduction

Sat, 30 May 2026 00:00:00 GMT

Photo credit Nilfanion, created using Ordnance Survey data, CC BY-SA 3.0. Before they could build anything else, they had to build fifteen miles of road. The valley between Loch Awe and Loch Fyne where the Shira Hydro-Electric Scheme would go had no road access at all - no rail, no quarry, no power, no place to put eight hundred construction workers. Work started in 1949 on access roads alone. By spring 1951, with the roads finally in, the scheme could begin properly. Six years later, in autumn 1957, Sron Mor power station went into operation as the first major pumped-storage power facility in Britain. The Hydro Board built it as an experiment, to gather operational data for the kind of grid that would soon need to handle nuclear baseload. That nuclear future arrived more slowly than expected. The little pumped-storage station kept working anyway.

Image: Nilfanion, created using Ordnance Survey data | CC BY-SA 3.0

Shira Hydro-Electric Scheme: Tom Johnston's Highland Hydro

Sat, 30 May 2026 00:00:00 GMT

Photo credit Nilfanion, created using Ordnance Survey data, CC BY-SA 3.0. The North of Scotland Hydro-Electric Board owed its existence to Tom Johnston, who as wartime Secretary of State for Scotland pushed the Hydro-electric Development (Scotland) Act 1943 through Parliament. The idea was elegant: a public body would build hydro stations across the Hi...

Image: Nilfanion, created using Ordnance Survey data | CC BY-SA 3.0

Shira Hydro-Electric Scheme: Three Dams, Three Designs

Sat, 30 May 2026 00:00:00 GMT

Photo credit Nilfanion, created using Ordnance Survey data, CC BY-SA 3.0. The scheme would impound the River Shira to create Lochan Shira, with a smaller reservoir, Lochan Sron Mor, sitting below it. The main dam was a round-headed buttress design - chosen after consideration of several alternatives based on the variable rock strata at the dam site - 2...

Image: Nilfanion, created using Ordnance Survey data | CC BY-SA 3.0

Shira Hydro-Electric Scheme: The Underground Cathedral

Sat, 30 May 2026 00:00:00 GMT

Photo credit Nilfanion, created using Ordnance Survey data, CC BY-SA 3.0. From Lochan Sron Mor, a tunnel six miles long and eleven feet in diameter ran out under the hills to Clachan power station on the banks of Loch Fyne. Half the tunnel was excavated in the first year. The station itself presented a choice between a surface building and an undergrou...

Image: Nilfanion, created using Ordnance Survey data | CC BY-SA 3.0

Shira Hydro-Electric Scheme: Edward MacColl's Reversible Station

Sat, 30 May 2026 00:00:00 GMT

Photo credit Nilfanion, created using Ordnance Survey data, CC BY-SA 3.0. Edward MacColl, the Hydro Board's first chief executive, had proposed a "reversible hydraulic station" at Loch Sloy back in 1936 while he was working for the Central Electricity Board. The idea was rejected as uneconomic. MacColl died in 1951, before he could see his concept buil...

Image: Nilfanion, created using Ordnance Survey data | CC BY-SA 3.0

Shira Hydro-Electric Scheme: The World's First Prestressed Gravity Dam

Sat, 30 May 2026 00:00:00 GMT

Photo credit Nilfanion, created using Ordnance Survey data, CC BY-SA 3.0. There was a third part of the scheme, off in the valley of the Allt na Lairige. Engineers wanted to build a dam there to feed a power station on the River Fyne, but a conventional mass gravity dam would have made the scheme uneconomic. Cheaper alternative: a prestressed concrete ...

Image: Nilfanion, created using Ordnance Survey data | CC BY-SA 3.0