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Lednock Tunnel [Lednock Intake]

Loch Lednock Reservoir, Glen Lednock, NW of Comrie, Perthshire.

Tunnel, Adit.

Adit entrance in the S shore of (Loch) Lednock Reservoir. This concrete-lined tunnel, which has a 9'-6" equiv. diameter, diverts water south from the reservoir to St Fillans Power Station on the shores of Loch Earn. The tunnel's outfall point is within the power station's surge shaft, 200ft below surface.

From a point E of Loch Boltachan, a branch of the tunnel referred to as the 'Boltachan Tunnel' extends ESE as far as an intake along the Boltachan Burn at NN 7142 2584. See: Boltachan Tunnel [Intake]

Alternate Names: Glen Lednock - St Fillans Tunnel

Notes: Given length is approx. & excludes the Boltachan branch.

Given 10 fig. NGR coordinates are taken from OS website on which satellite view (2025) clearly shows the adit mouth and associated trench during very low water level conditions. Under normal conditions, the adit will be completely submerged.

The tunnel intake gatehouse is located at [NN 7137 2940], SSW of the adit entrance.

Name of 'Lednock Tunnel' shown on SSE general layout map.

Hydrographic Feeds: Lednock Reservoir

Hydrographic Resurgences: St Fillans Power Station Surge Shaft