Qualla: Glendoe Hydro Scheme

Glendoe Hydro Scheme: Introduction

Sat, 30 May 2026 00:00:00 GMT

Photo credit Bewahrerderwerte, CC BY-SA 4.0. Queen Elizabeth pressed the button on 29 June 2009, and water that had been falling from the Glendoe plateau for thousands of years suddenly had a job to do. Six weeks later, somewhere deep inside a tunnel boring through nearly 2,000 feet of Highland rock, the job stopped. A section of headrace collapsed, the turbines fell silent, and one of Scotland's most ambitious hydro projects became one of its longest legal disputes. The Glendoe scheme sits in the Monadhliath Mountains above Fort Augustus, invisible from any road or house in the area. From the air, only the dam across the River Tarff hints at the engineering hidden beneath the heather.

Read more: Glendoe Hydro Scheme on Qualla

Image: Bewahrerderwerte | CC BY-SA 4.0

Glendoe Hydro Scheme: A Scheme the 1960s Almost Built

Sat, 30 May 2026 00:00:00 GMT

Photo credit Des Colhoun, CC BY-SA 2.0. The North of Scotland Hydro-Electric Board mothballed Glendoe in the 1960s along with most of its remaining big-scheme ambitions. The political climate had soured on flooding glens; amenity objections killed nearly every project the Board had on its drawing boards. Glendoe was th...

Read more: Glendoe Hydro Scheme on Qualla

Image: Des Colhoun | CC BY-SA 2.0

Glendoe Hydro Scheme: The Highest Head in Britain

Sat, 30 May 2026 00:00:00 GMT

Photo credit Sarah McGuire, CC BY-SA 2.0. Hydropower lives or dies on hydraulic head—the vertical distance water falls before hitting the turbine. Glendoe drops 2,000 feet (600 metres) from reservoir to powerhouse, the highest of any scheme in the United Kingdom. That altitude difference, combined with Highland rainfall,...

Read more: Glendoe Hydro Scheme on Qualla

Image: Sarah McGuire | CC BY-SA 2.0

Glendoe Hydro Scheme: Operation Bathplug and Beyond

Sat, 30 May 2026 00:00:00 GMT

Photo credit wfmillar, CC BY-SA 2.0. A refurbished Herrenknecht boring machine, named Eliza Jane after a competition by local schoolchildren, chewed through Highland gneiss to cut the headrace. The Pöyry engineers convinced Hochtief that the rock was sound enough to leave largely unlined—less than one per cent of th...

Read more: Glendoe Hydro Scheme on Qualla

Image: wfmillar | CC BY-SA 2.0

Glendoe Hydro Scheme: The Andritz Pelton and Its Six Jets

Sat, 30 May 2026 00:00:00 GMT

Photo credit Mike McBey, CC BY 2.0. Engineers debated between a Francis turbine and a Pelton wheel for months. A Francis turbine starts and stops faster, but it requires a surge shaft to manage pressure changes, and the slope between reservoir and powerhouse offered no good site for one. A Pelton turbine is slower ...

Read more: Glendoe Hydro Scheme on Qualla

Image: Mike McBey | CC BY 2.0

Glendoe Hydro Scheme: The Court of Appeal Splits Two to One

Sat, 30 May 2026 00:00:00 GMT

Photo credit Sarah McGuire, CC BY-SA 2.0. BAM Nuttall built a diversion tunnel around the collapse, fully lined with 20 inches of waterproof concrete. Generation restarted in August 2012. The argument over who should pay took longer than the repair. Robert Galbraith QC, appointed to adjudicate in 2011, sided with Hochtie...

Read more: Glendoe Hydro Scheme on Qualla

Image: Sarah McGuire | CC BY-SA 2.0