| Castlereigh Dam | |
| Location Map: | Sri Lanka |
| Location Map Size: | 270px |
| Coordinates: | 6.8733°N 80.5664°W |
| Country: | Sri Lanka |
| Location: | Hatton, Central Province |
| Purpose: | P |
| Status: | O |
| Opening: | January 1965 |
| Owner: | CEB |
| Dam Type: | G |
| Dam Crosses: | Kehelgamu Oya |
| Plant Name: | Wimalasurendra Power Station |
| Plant Coordinates: | 6.9086°N 80.525°W |
The Castlereigh Dam (also spelled Castlereagh) is a gravity dam built across the Kehelgamu Oya, a major tributary to the Kelani River, approximately 3km (02miles) south-west of Hatton, in the Central Province of Sri Lanka.[1]
The dam creates the iconic Castlereigh Reservoir, which is almost entirely maintained by the inflow of water from the Kehalgamu Oya. Water from the reservoir is diverted to the Wimalasurendra Power Station, located approximately 12km (07miles) downstream at, near Norton Bridge. The power station discharges the water into the Norton Reservoir, created by the Norton Dam, located at the same site.
The power station consists of two 25-megawatt units, totalling the plant capacity to . Both units were commissioned in .[2]
The Castlereigh Reservoir is also home to the Castlereigh Water Airport, registered under the IATA code NUF.[3]