Authorities have opened the spill gates of the Kotmale Gamini Dissanayake Reservoir following heavy rainfall in the upper catchment areas, as adverse weather continues to affect Sri Lanka.
The decision was taken to ensure the safety of the reservoir and to reduce the risk of severe flooding in downstream areas. According to instructions issued by the Director General of the Mahaweli Authority and the Water Management Secretariat, the reservoir's spill gates and sluice gates began to be opened gradually from 3:00 p.m. on August 3, 2026.
Officials expect approximately 250 cubic metres of water per second to be released into the Kotmale Oya. However, they noted that the discharge rate may be adjusted depending on the volume of water flowing into the reservoir.
As a result of the water release, there is an increased risk of flooding in low-lying areas along the Kotmale Oya, including Nugawela, Riverside, and Mawathura. Areas along the Mahaweli River from Ulapane through Gampola, Weligalla, Gelioya, Peradeniya, Katugastota, and Polgolla are also expected to face a higher risk of inundation.
The Mahaweli Authority has urged residents in these vulnerable areas to remain highly vigilant, safeguard their lives and property, and take all necessary precautionary measures until conditions improve.
