Backwater Reservoir

Backwater Reservoir is a reservoir in north west Angus, Scotland. The reservoir's sole purpose is to provide drinking water, and as such, it supplies Angus, Dundee, and parts of Perth and Kinross. Backwater, together with the smaller Lintrathen Reservoir 4 kilometres to the south, is capable of supplying some 300,000 people with drinking water.

Source: Wikipedia