Gartmorn Dam is an artificial freshwater lake 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.