The reservoir, which is around 435 metres (1,427 ft) long, was built by John Laing & Son in around 1900.

[1] It involved damming the River Ellen above Uldale to provide water for Aspatria and Silloth.

[1] It is named after Chapelhouse Farm which is close by, and it is owned by United Utilities.

[2] As part of the United Utilities project to supply West Cumbria from Thirlmere, the extraction of water from Chapelhouse Reservoir ceased in October 2022.

[3] Decommissioning of Chapelhouse Reservoir, along with Overwater and Crummock Water, is expected to begin in 2025.