Ceannacroc Power Station

Ceannacroc is a medium sized power station housing a single turbine and built entirely underground with an unlined access tunnel with horseshoe arch. The station uses water from Cluaine dam (see separate item) which is conveyed through a pressure tunnel bored through solid bedrock. The tailrace discharges into the River Morriston which is dammed downstream by Dundreggan dam (see separate item) allowing the water to be used twice more at Glenmorriston and Livishie power stations (see separate items). The station house a 22MW set and a 4MW compensation set all of which were refurbished along with the turbine hall interior in the late 1990s. Ceannacroc is an early example of a subterranean power station and amongst the earliest to be developed in the UK. The Great Glen scheme is characterised by the use of underground stations with other examples including Livishie and Glenmorriston. The design of subterranean stations was pioneering for this date with most developments using surface stations and steel penstocks for the pressure system. PL Payne, 1988, 5; E Wood, 2002, 38; J Miller, 2002.

http://www.corestore.org/Cean.htm [retrieved 14 November 2011]

The Great Glen scheme: Garry/Moriston

The garry part of the scheme uses the storage facility at Loch Quoich to supply Quoich power station via a tunnel from the dam, which is a rockfill type. Two further dams were required at the west end ofthe loch. The outflow goes vis the River Garry to Loch Garry, and eventually via a tunnel to Invergarry power station at Loch Oich. There is a dam at the east end of Loch Garry. A fish stopper and trap were built down stream of Quoich power station.

Storage for Moriston section was provided by damming Loch Loyne and Loch Cluanie, and interconnecting them by a tunnel. A second tunnel from Loch Cluanie supplies Ceannacroc power station which discharges int the River Moriston, which in turn feeds Loch Dundreggan. This loch is also fed by the outflow of Livishie power station, supplied by a system of aqueducts. Glenmoriston power station is just below the Dundreggan dam. Its outflow reaches the River Moriston at Loch Ness via a tunnel. These three power stations were built underground for environmental reasons. The control centre for the the entire scheme is at Fort Augustus. The total output capacity is 114MW. The scheme was built between 1949 and 1962.

Information from NRHE catalogue number WP007424 compiled by George Walker in 2005.