Site Records

Misgeach Power Station

Misgeach is a very small power station which generates electricity from the release of compensation water. It's part of the Deanie system. It's an ingenious piece of design.

Water from the south side of the Uisge Misgeach is collected by an aqueduct system and led, via a short tunnel, to a small headpond known as the 'South Headpond'. Water from the north side of the glen, and the Uisge Misgeach itself, is captured by an aqueduct and led to a similar structure called the 'North Headpond'. The water from the South Headpond crosses the glen in an inverted syphon and discharges into the North Headpond.

A tunnel has been built from the Uisge Misgeach to a point near Loichel dam, on Loch Monar, a couple of miles away. The combined waters in the North Headpond flow into this tunnel, down a slope shaft.

There is a legal requirement to maintain a statutory compensation flow in the Uisge Misgeach. A small power station has therefore been built at the lowest point of the inverted syphon. As long as there is enough water in the system, the power station will run, using some of the water flowing through the inverted syphon, and discharging the required compensation water into the river.

However, when the flow in the aqueducts is too low to provide the statutory flow (or if the power station is out of action for any reason), water must be found elsewhere. The portal to the Loichel tunnel is just behind the power station, and a pipe has been routed from this portal to the power station, where a valve allows water to be drawn from Loch Monar when required.

The photo below, taken from the South Headpond, has been annotated to clarify the various components of the system:

A similar view from the North Headpond. Note the measuring weir in the river, which records flow.

The following photos illustrate the range of flow conditions that have to be managed. This photo is taken at the North Headpond, and shows the mouth of the slope shaft which leads the water from the headpond down to the Loichel tunnel. In drought:

...and in spate!!!

Misgeach power station in operation. A slight leak of spray from the disperser valve, but the main flow of water is coming from the turbine outlet on the left.

This is a sight I've very seldom seen: it appears that this station isn't in operation very often, technical problems perhaps.

97% of my visits have found the turbine not running, and the water being discharged from the dispersion valve, like this:

As mentioned, the portal of the Loichel tunnel is immediately behind the power station. The pipe which allows compensation water to be drawn from loch Monar is clearly visible.

A nice 'artistic' shot to sign off: compensation water being discharged from Misgeach on a fine but bitterly cold winters day - the spray coating the area downwind with thick ice:

Words and images © 2003 Michael J. Ross