瑟尔米尔水库是英格兰的水库，始建于十九世纪，长6.05公里、宽1.78公里，面积3.25平方公里，海拔高度178米，湖岸线长度15公里，最大水深40米，湖中有两座岛屿。

Thirlmere is a reservoir in the Borough of Allerdale in Cumbria and the English Lake District. It runs roughly south to north, with a dam at the northern end, and is bordered on the eastern side by the A591 road and on the western side by a minor road.