Will the Maha Oya rise in the next hour?

In the next hour, of the 2 gauges on the Maha Oya with a forecast, 2 rising. This is a forecast from the recent trend, the gauges upstream and rain, not an official warning.

Which gauges are on the Maha Oya?

From upstream to downstream: Giriulla, Badalgama.

Where does this come from and how often does it update?

River readings come from the Department of Irrigation's gauges, roughly once an hour, and this page checks for new ones every minute. This site is independent and not an official warning service: follow the Disaster Management Centre and call 117 in an emergency.

Maha Oya

1 of 2 gauges at alert or above · updated 12:04 am, 51 min ago

As of Tue, 27 Oct, 12:04 am (Sri Lanka time), 1 of the 2 reporting gauges on the Maha Oya are at or above an official mark (Alert, Minor flood or Major flood): Badalgama (18.1 ft).

River map

GaugeReservoirTap a gauge or reservoir for details.

Upstream

Downstream (sea)

Rain on this river

Fell, 24 h (gauge)Satellite, 24 hForecast, next 24 h

Badalgama941107.5

Giriulla771097.2

Gauge = what the gauge's sensor recorded. Satellite and forecast are estimates over the hills above each gauge. It can differ from the gauges.

Rain map

When does the Maha Oya flood?

Flood warnings come mostly in November.

It’s October: floods are less common than in November, but they do happen.

Recent floods

27 Nov – 30 Nov 2025Badalgama, Giriulla (major flood)
21 Oct – 26 Oct 2025Badalgama, Giriulla (major flood) · estimated
26 Nov – 2 Dec 2024Badalgama, Giriulla (major flood) · estimated

Every day since 2022, year by year

Official flood map

The Irrigation Department has mapped where past floods on the Maha Oya reached:

2016: 92 Grama Niladhari divisions in 9 divisional secretariat areas: Divulapitiya, Katana, Mirigama, Negombo, Alawwa, Narammala, Pannala, Dankotuwa, and 1 more

This shows where a past flood reached, not a flood now. A bigger flood can go further.

Flood maps: Irrigation Department of Sri Lanka

Flood help & emergency numbers

Common questions

Is Maha Oya flooding now?: As of Tue, 27 Oct, 12:04 am (Sri Lanka time), 1 of the 2 reporting gauges on the Maha Oya are at or above an official mark (Alert, Minor flood or Major flood): Badalgama (18.1 ft).
Will the Maha Oya rise in the next hour?: In the next hour, of the 2 gauges on the Maha Oya with a forecast, 2 rising. This is a forecast from the recent trend, the gauges upstream and rain, not an official warning.
Which gauges are on the Maha Oya?: From upstream to downstream: Giriulla, Badalgama.
Where does this come from and how often does it update?: River readings come from the Department of Irrigation's gauges, roughly once an hour, and this page checks for new ones every minute. This site is independent and not an official warning service: follow the Disaster Management Centre and call 117 in an emergency.