The first site considered, Cow Green, was above Cauldron Snout and was in a sensitive habitat area, so Balderhead was built instead.

[4] Cow Green Reservoir was built later, though the approval process was protracted due to the loss of habitat for the Teesdale violet plant.

[1] When full, the reservoir can hold 507,914,900 cubic feet (14,382,549 m3) and has an overall perimeter length of 5 miles (8 km).

[2] The catchment upstream of the reservoir is a mixture of rough grazing land and moorland which covers 12 miles (20 km).

[14][15] Recreationally, the reservoir is used by the Teesdale Sailing and Watersports Club for windsurfing, canoeing and kite surfing.