Located 12km from Dublin City Centre, the Bohernabreena Reservoir and Waterworks lie in the Valley of Glenasmole at the foot of Kiltipper Mountains.
Construction began in 1883 and was complete by 1886. There are two reservoirs, referred to as the Upper and the Lower Lakes. The Upper or Reservoir which provides the drinking water supply, has a surface area of 0.23 km2, a maximum capacity of 1.56 x 106m3 and a catchment area of 7km2. It is surrounded by an embankment 200m long and 21m high.
The valve tower located along the embankment allows water to be taken at three different depth levels. Peaty waters from surrounding hills is channelled around the Upper Reservoir and directed to the Lower Reservoir via a canal which can be accessed.
The Lower Reservoir is has a surface area of 0.12km2 , a maximum capacity of 0.5 x 106m3 and a catchment area of 21 km2. New additional spill ways which can be accessed have recently been constructed around the reservoirs to take excess flood waters.