Hydroelectricity is the oldest and historically the principal source of electricity generation in Sri Lanka, holding a share of 48% of the total available grid capacity in December 2013 and 58% of power generated in 2013.
Hydroelectric power generation has been constantly under development since the introduction of the national grid itself, but its market share is declining because suitable new sites are scarce.
Currently, ten large hydroelectric power stations are in operation, with the single largest hydroelectric source being the Victoria Dam.
Although a large portion of the country's hydroelectric resource are tapped, the government continues to issue small hydro development permits to the private sector, for projects up to a total installed capacity of 10 MW per project.

State-run hydroelectric developments are categorized into three main geographic sectors.

Laxapana Complex consists of six main dams with related power stations — Broadlands, Canyon, Castlereigh, Laxapana, Maskeliya, and Norton dams.

Mahaweli Complex consists of eight dams and related power stations: Bowatenna, Kotmale,  Moragahakanda, Polgolla, Randenigala, Rantembe, Upper Kotmale, and the Victoria dams.

Samanala Complex consists of the Gal Oya, Kukule Ganga, Samanala, and Udawalawe dams.
Hydroelectricity is the oldest and historically the principal source of electricity generation in Sri Lanka, holding a share of 48% of the total available grid capacity in December 2013 and 58% of power generated in 2013. Hydroelectric power generation has been constantly under development since the introduction of the national grid itself, but its market share is declining because suitable new sites are scarce. Currently, ten large hydroelectric power stations are in operation, with the single largest hydroelectric source being the Victoria Dam. Although a large portion of the country's hydroelectric resource are tapped, the government continues to issue small hydro development permits to the private sector, for projects up to a total installed capacity of 10 MW per project.
State-run hydroelectric developments are categorized into three main geographic sectors.
Laxapana Complex consists of six main dams with related power stations — Broadlands, Canyon, Castlereigh, Laxapana, Maskeliya, and Norton dams.
Mahaweli Complex consists of eight dams and related power stations: Bowatenna, Kotmale,  Moragahakanda, Polgolla, Randenigala, Rantembe, Upper Kotmale, and the Victoria dams.
Samanala Complex consists of the Gal Oya, Kukule Ganga, Samanala, and Udawalawe dams.
Electricity sector in Sri Lanka