Castlereigh Dam

Castlereigh Dam is a gravity dam in Sri Lanka's central highlands that holds back water to form a large reservoir surrounded by forested slopes and tea estates. The structure stands as a concrete barrier engineered to control the flow of the Kehelgamu Oya stream and supply water for hydroelectric purposes.

Construction began in 1958 with German engineering expertise guiding the project from its inception. The creation of the reservoir required relocating settlements and businesses that had occupied the valley floor.

The reservoir development led to the displacement of an established Hindu temple and altered the daily routines of tea estate workers in the surrounding region.

The dam is accessible by foot and provides vantage points for viewing the full structure and reservoir from different angles. The best time to visit is during the dry season when water levels remain steady and visibility is clearer across the landscape.

A water airport operates on the reservoir where small aircraft can land directly on the surface. This unusual facility demonstrates an inventive approach to using the water body for multiple purposes beyond typical dam functions.