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Quoich Tunnel [Access Adit]

Quoich Power Station, Kingie, Glen Garry, Inverness-shire.

Tunnel, Hydro electric scheme (1955-).

"From the dam, water is led to the power station by a low-pressure tunnel, 12843ft [3914.5m] long, and horseshoe in section, with an equivalent diameter of 11' 6". There are no sidestream intakes. The low-pressure tunnel terminates at the base of the surge chamber, which is of the orifice type, with an upper expansion chamber. The chamber is 169ft [51.5m] deep, the top 40ft being 45ft in diameter (the expansion chamber), the remainder of the shaft being 30ft in diameter. From the base of the surge chamber, the water falls down a vertical high-pressure shaft, 158ft [48m] deep by 11' 6" in diameter. From the base of the shaft, the remaining distance to the power station is covered by a high-pressure tunnel 1440ft [439m] long, followed by a steel penstock tunnel 820ft [250m] long, to the main inlet valve.

"There's no works or gatehouse associated with the surge shaft at Quoich; it's a simple fenced hole in the ground on the open hillside above the power station, reached by a hill track... A short distance down the hill below the surge shaft is the construction adit, used in the building of the tunnel, and still used for access for maintenance and inspection... the sign [on the adit gate] warns that it's an 'unlined access tunnel'" [Corestore]

Cross section states 12843ft & 2200ft for the low- & high-pressure tunnels respectively, and a VR from 700 to 330ft [=112m].

Alternative Names: Quoich Power Station

Notes: Part of the Garry-Moriston Hydro-Electric Scheme, aka 'Great Glen Scheme'.

At 320 meters long and 38 meters high, the dam at Loch Quoich is the largest rockfill structure in Scotland. It supplies water via tunnel to two power stations, each producing 20 MW of power.

Given elevation is for the access adit. The top of the surge shaft is at 214m alt [OS site].

Hydrographic Feeds: Loch Quoich

Hydrographic Resurgences: Kingie Pool