# Sri Lanka reservoir management and flood warnings

> Live situation record from CLSTR: https://clstr.news/situations/sri-lanka-reservoir-management-and-flood-warnings
> Updated: 2026-10-26T04:13:07.000Z. Sources: 12. Developments: 2.

Following significant and continuous heavy rainfall, the Sri Lankan Department of Irrigation has begun releasing water from several major reservoirs to manage rising water levels.

Initial actions included opening eight spill gates at the Deduru Oya Reservoir, discharging 16,500 cubic feet per second, and opening eight gates at the Rajanganaya Reservoir to discharge 7,884 cubic feet per second into the Kala Oya. 

As rainfall continued, authorities expanded water releases to include the Kukule Ganga and Kalawewa reservoirs. The Department of Irrigation has issued warnings for residents in low-lying areas near the Deduru Oya, Kala Oya, and Kuda Ganga river basins to remain highly vigilant regarding changing water levels.

## Timeline

### 2026-10-26: Sri Lanka irrigation authorities open reservoir gates due to heavy rain

Sri Lanka's Department of Irrigation has opened gates at several major reservoirs, including Deduru Oya and Rajanganai, to manage rising water levels caused by heavy rainfall.

10 sources. https://clstr.news/cluster/prime-minister-harini-announces-increased-funding-for-education-reforms

### 2026-10-22: Deduru Oya Reservoir opens spill gates amid flood warnings

Authorities have opened spill gates at the Deduru Oya and Rajanganaya reservoirs due to heavy rainfall, issuing flood warnings for multiple low-lying areas in Sri Lanka.

2 sources. https://clstr.news/cluster/deduru-oya-reservoir-opens-spill-gates-amid-flood-warnings

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Cite as: Sri Lanka reservoir management and flood warnings. CLSTR, https://clstr.news/situations/sri-lanka-reservoir-management-and-flood-warnings