Not official. In an emergency call 117

Data: Irrigation Dept & others · Made by @shakeeb_x

  • Home
  • Towns
  • Reservoirs
  • History
Sri Lanka Water LevelsLive river-gauge readings
Basins
  • Aththanagalu Oya
  • Deduru Oya
  • Gal Oya
  • Gin Ganga
  • Heda Oya
  • Kala Oya
  • Kalu Ganga
  • Kelani Ganga
  • Kirindi Oya
  • Kumbukkan Oya
  • Ma Oya
  • Maduru Oya
  • Maha Oya
  • Mahaweli Ganga
  • Malwathu Oya
  • Mee Oya
  • Menik Ganga
  • Nilwala Ganga
  • Walawe Ganga
  • Yan Oya
ReservoirsNewsHistoryHelp@waterlevelslk
ENසිංத
Home›Flood history›Gal Oya

When does the Gal Oya flood?

Flood warnings on the Gal Oya come mostly between November and December.

Since 23 Nov 2025, this gauge has recorded flooding on 0 days and alert levels on 0 days. The most recent flood was 20 Jan – 24 Jan 2025 (minor flood), estimated.

Below each line is what the river gauges recorded; above it, our estimate of how high the rivers ran, going back to 2022. Updated 27 Oct, 1:00 am (Sri Lanka time). Live Gal Oya levels →

Flood warnings by day, one row per year

AlertMinor floodMajor floodEstimatedRecorded
NE monsoon
Inter-monsoon
SW monsoon
Inter-monsoon
JJanFFebMMarAAprMMayJJunJJulAAugSSepOOctNNovDDec
2026
2025~5d
2024~8d
2023~5d
2022

Tap or hover a day for details. Earlier years are estimates.
Gauge records start 16 Oct 2026

When do flood warnings happen?

Share of days in each month with at least one gauge at alert or worse on the Gal Oya.

JanFebMarAprMayJunJulAugSepOctNovDec
Estimated, 2022 to now Measured at gauges, Nov 2025 to now

Biggest flood events on the Gal Oya

Runs of days with minor or major flooding, ranked by the worst day.

Year by year

Gal Oya: about 0 affected days a year in gauge records since 16 Oct 2026.

Before 16 Oct 2026 there are no gauge records here; estimates suggest about 33 affected days a year in 2022–2025.

YearAffected daysMajor floodMinor floodAlertWorst day
2026(so far)Recorded from 16 Oct
2
–
2
–
Major flood 0Minor flood 2Alert 0
Worst day: 18 Feb · minor flood (estimated)
2025Estimated
27
–
5
22
Major flood 0Minor flood 5Alert 22
Worst day: 20 Jan · minor flood (estimated)
2024Estimated
32
–
8
24
Major flood 0Minor flood 8Alert 24
Worst day: 11 Jan · minor flood (estimated)
2023Estimated
55
–
5
50
Major flood 0Minor flood 5Alert 50
Worst day: 21 Nov · minor flood (estimated)
2022Estimated
17
–
–
17
Major flood 0Minor flood 0Alert 17
Worst day: 8 Nov · alert (estimated)

Affected means at least alert level. A day counts once, at the worst level any gauge reached. Years before the gauge records start are estimates.

Flood history by gauge on the Gal Oya

  • Ampara

About this data

Measured: the highest level each gauge reached that day, compared with the Department of Irrigation’s alert, minor-flood and major-flood levels.

Estimated: for years before the gauge records here begin, we estimate how high each river ran from a global river-flow model. These are not official warnings. They show the flood seasons and the big floods well, but can miss the exact day or gauge, especially on small rivers.

Sources: Department of Irrigation river gauges; earlier gauge readings saved by lk_irrigation; river-flow estimates by Open-Meteo. Download the daily records.

Sri Lanka Water Levels

Live river and reservoir levels across Sri Lanka, with flood forecasts.

Rivers

  • Aththanagalu Oya
  • Deduru Oya
  • Gal Oya
  • Gin Ganga
  • Heda Oya
  • Kala Oya
  • Kalu Ganga
  • Kelani Ganga
  • Kirindi Oya
  • Kumbukkan Oya
  • Ma Oya
  • Maduru Oya
  • Maha Oya
  • Mahaweli Ganga
  • Malwathu Oya
  • Mee Oya
  • Menik Ganga
  • Nilwala Ganga
  • Walawe Ganga
  • Yan Oya

Explore

  • Home
  • Reservoirs
  • Flood estimates
  • Flood news
  • Flood history
  • Flood help
  • About
  • Research
  • Data status
  • GitHub

Data and credits

Readings from the Department of Irrigation and the Mahaweli Authority. Warnings from the Disaster Management Centre. Rain forecasts from Open-Meteo. Map © OpenStreetMap contributors; some river lines from the Department of Irrigation.

Not an official warning service. In an emergency, call 117.

© 2026 Sri Lanka Water Levels. Built in Sri Lanka. · Made by @shakeeb_x · Automated updates: @waterlevelslk

EN·සිංහල·தமிழ்