The reservoir was formed by the damming of the Eye Brook. It was built between 1937 and 1940 by Stewarts &amp; Lloyds (supervised by Geoffrey Binnie of Binnie &amp; Partners) to supply water to its Corby steel works. During the Second World War it was used in May 1943 as a practice site for the Dambuster raids, standing in for the Möhne Reservoir; a plaque commemorates this.