Gartmorn Dam is an artificial freshwater loch north-east of Alloa, Clackmannanshire, Scotland, UK, built in 1711-12 as a reservoir to supply water to hydraulic machines used in Alloa's mining industry. It was commissioned by John Erskine, 23rd and 6th Earl of Mar, to designs by George Sorocold, and is one of the earliest constructed reservoirs in Scotland.

Gartmorn Dam
View across Gartmorn Dam
The surface of Gartmorn Dam in 2006
Location of Gartmorn Dam in Scotland
Location of Gartmorn Dam in Scotland
Gartmorn Dam
Location of Gartmorn Dam in Scotland
LocationClackmannanshire
Coordinates56°07′43″N 3°44′21″W / 56.1285°N 3.7393°W / 56.1285; -3.7393
TypeReservoir
Basin countriesScotland
Construction engineerGeorge Sorocold
First flooded1712 (1712)

History edit

Gartmorn Dam was commissioned by John, Earl of Mar, a Scottish noble and estate owner, who had received training in drawing and architectural design, and was said to be 'infected with the desease of building'.[1] Its purpose was to provide a sufficient head and volume of water to drive mining pumps supporting the extractive industry of Alloa.[2]

The dam, lake and associated waterworks were designed by and built, from 1711 to 1712, by English civil engineer George Sorocold.[3] Sorocold caused the construction of a weir on the Black Devon waterway at Forestmill, raising its waters by 16 foot (4.9 m), and a lade to carry water about 2 miles (3.2 km) westward to Gartmorn, where it was impounded by an earth dike. The lake formed has a surface of about 160 acres (65 ha), reaches a maximum depth of 37 feet (11 m) deep,[nb 1] and it situated about 160 foot (49 m) above the level of the River Forth, and 92 foot (28 m) above Alloa. It is considered the earliest constructed reservoir in Scotland, and was for many years the largest artificial lake in Scotland.[2]

The reservoir's dam, some 320 yards (290 m) in length, was reconstructed in hewn stone in 1785 at a cost of several thousand pounds; and extensive repairs were made in 1827, to avert concerns that the structure might fail and inundate the lower parts of the town.[2]

In contemporary times, Gartmorn Dam is used for leisure activities. The weir and lade remain in good condition. In 2013, Scottish Water spent £440,000 to maintain the dam headwall and improve emergency water level reduction systems.[4]

Notes edit

  1. ^ A number of nineteenth-century descriptions of the lake use a measure "being sufficient to carry a seventy-four gun ship" to emphasise the depth of the lake.[2]

References edit

  1. ^ v. Ehrenstein, Christoph. "Erskine, John, styled twenty-second or sixth earl of Mar and Jacobite duke of Mar". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/8868. (Subscription or UK public library membership required.)
  2. ^ a b c d "Alloa". The New Statistical Account of Scotland. 1845. p. 8.   This article incorporates text from this source, which is in the public domain.
  3. ^ Stewart, Margaret (2013). "John Erskine, 6th and 11th Earl of Mar (1675–1732): Architecture, Landscape and Industry". Architectural Heritage. 23 (1). Edinburgh University Press: 101–106. doi:10.3366/arch.2012.0035.
  4. ^ Forsyth, Valerie (14 February 2018). "A Walk in the Past: When the dam runs dry". Alloa Advertiser. Retrieved 14 February 2018.