Loch Beannacharan, Deanie Power Station

Deanie power station receives water from Loch Monar via a 9 km tunnel which culminates in a surge shaft set into the hillside behind the station. The station itself is located in an excavated underground chamber which is accessed by a sloping vehicular access tunnel. The turbine hall contains two turbines with a combined capacity of 38 megawatts. This station is a good example of a medium sized underground station. Where it was possible to build them underground stations were utilised on this scheme because of concerns that the development of hydro in this area would have a negative effect on the scenic amenity. In line with the wishes of James Shearer local stone was used as widely as possible during construction and it is likely that the stone for the construction of the arched entrance was salvaged from the excavations for the main chamber. PL Payne, 1988, 5; E Wood, 2002, 38; J Miller, 2002.

The Affric/ Beauly scheme

The work was begun on the construction of Mullardoch Dam in 1947. This is of the mass gravity type and is 2385 feet in length by 160 feet in height, impounding 7.5 million cubic feet of water. A tunnel was excavated from Loch Mullardoch to Loch Benevan, and another from the latter loch to Fasnakyle, the main power station on the River Affric, both tunnels being over three miles in length. The Fasnakyle tunnel splits into three steel-lined tunnels near the power station, each supplying a 22,000kW vertical Francis turbo-alternator.

The second stage of the scheme involved the Rivers Farrar and Beauly. Water is impounded in Loch Monar by the Monar Dam, supplying the Deanie power station at the west end of Loch Bennacharan which is dammed at the east end to feed Culligran power station, whose outflow to the River Farrar then flows into the River Glass. These power stations generate 38MW and 24MW respectively. The River Glass flows into the River Beauly which has dams and power stations at Aigas and Kilmorack, each a 20MW run of river station. These dams are provided with flood control, Borland fish passes and compensation water facilities with or without generation. The scheme was completed in 1963.

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