Is Ellagawa flooding now?

As of Tue, 27 Oct, 12:05 am (Sri Lanka time), the Kalu Ganga at Ellagawa was 31.8 ft, close to the 32.8 ft alert level, and rising.

Will the Kalu Ganga at Ellagawa rise in the next hour?

In the next hour the Kalu Ganga at Ellagawa could rise to about 32.0 ft (31.8–32.2 ft). This is a forecast from the recent trend, the gauges upstream and rain, not an official warning.

What is the flood level at Ellagawa?

The official marks for this gauge are alert 32.8 ft, minor flood 35.1 ft, major flood 40.0 ft. Alert means the river has reached the alert mark: move valuables up and charge your phone. Minor flood means water is spilling over low ground, and major flood means move to safety.

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.

Ellagawa Kalu Ganga water level today (live)

Official warning:

An amber warning says minor flooding may occur within 24 hours in low-lying Kalu River floodplain areas of Ratnapura and Kalutara districts; residents and drivers should remain vigilant and take precautions.

Irrigation Department

Reading at 12:05 am · 51 min ago

Normal

31.8 ft

Near alert: 1.0 ft below the alert mark, rising

Next hour

Rising slowly

Next 24 hours

Could reach alert level in ~8 hours

Likely to reach alert level around 8 am this morning (in about 7 hours) (about 70% chance).

Details

Likely to reach alert level around 8 am this morning (in about 7 hours) (about 70% chance).

Published as 9.70 m (alert 10.0 m, minor flood 10.7 m, major flood 12.2 m)

Elevated river-flow outlook this week.

In	Level	80% range	At
1h	32.0 ft	31.8 to 32.2	1:05 am
3h	32.2 ft	31.8 to 32.8	3:05 am
6h	32.6 ft	31.6 to 33.6	6:05 am
12h	32.8 ft	31.4 to 36.2	12:05 pm
24h	33.7 ft	29.0 to 41.4	12:05 am

Alert (32.8 ft): likely, about 7 in 10, from about 8:05 am
Minor flood (35.1 ft): possible, about 5 in 10, from about 11:05 am
Major flood (40.0 ft): unlikely, about 2 in 10

Local trend

+0.3 ft/h

Upstream avg

+0.1 ft/h

Rain that fell: 0.0 mm in the last 3 hours, 99 mm in the last 24 hours at this gauge (heavy rain)
Rain forecast: 27 mm in the next 24 hours over the catchment (moderate rain). Forecast model estimate.

Satellite estimate of rain over the catchment: 58.4 mm in the last 6 hours, 131.1 mm in the last 24 hours (to 12:30 am). It can differ from the gauges. GSMaP data by Japan Aerospace Exploration Agency (JAXA)

Rathnapura 1.4mm

· Outlook: the GloFAS global flood model has river flow at 461 m3/s in its highest member within 7 days, above the 1-in-20 level (285 m3/s). This is a heads-up only; it does not change the levels above.
· Part of the range is above the highest level this model has seen (25.5 ft); treat it as a rough guide.
· Some rain is forecast over the catchment: about 27 mm in the next 24 hours (ensemble range 8 to 37 mm).

How this is worked out
· Latest level at Ellagawa and recent change, plus upstream gauges: Rathnapura.
· Forecast model estimate of catchment rain (Open-Meteo, area average over 9 grid cells above Ellagawa): 55 mm modelled for the last 24 hours, 27 mm forecast for the next 24 hours, with ECMWF ensemble spread.
· The 1, 3, 6, 12, 24 hour steps use this gauge's own recent changes and the other gauges on the river (fitted to about 11 months of hourly readings, including the November 2025 Ditwah floods); where this was tested against 'level stays the same' it missed by less.
· The 24 hour steps read the rain the satellite measured over Ellagawa's catchment (JAXA GSMaP, corrected for how it reads here), with rain beside the gauge and rain on the channels upstream timed separately (about 9 h from beside the gauge, about 8 h from upstream). Tested storm by storm it was closer than the version that reads the weather model's rain.
· Heavy rain upstream is part of the 12, 24 hour steps: rain that has fallen or is forecast over the catchment above Ellagawa raises the level, and the top of the range allows for the heavier forecast rain. Tested storm by storm (leaving each storm out, Ditwah included) it was closer than the river's own trend alone.

Is this right?

Each answer helps us improve the forecast for your area.

Water level

This gauge’s forecasts: the next hour is typically off by about 0.08 ft; 24 hours ahead, by about 3.7 ft (last 30 days, 24 checks).

When does Ellagawa flood?

Flood warnings come mostly between November and December.

It’s October: usually a quieter month here, though heavy rain can still bring floods.

Recent floods

29 Nov – 1 Dec 2025Minor flood
4 Jun 2024Minor flood · estimated
25 May – 30 May 2024Major flood · estimated
Biggest since 2022:31 Oct – 18 Nov 2023Major flood · estimated

Every day since 2022, year by year

Other stations

Along the Kalu Ganga

Arrows show the change over the last 3 hours.

In the newsNews reports, not official.

RainSource: Newswire26 Oct, 7:30 pm (5 h ago)
Several rivers reach alert levels following heavy rainfall(opens the news site in a new tab)
The Irrigation Department has reported minor flood levels at three monitoring stations in the Kalu Ganga basin, while several other…
RiverSource: Newswire26 Oct, 11:58 am (13 h ago)
Minor flooding likely in Kalu Ganga Basin within next 24 hours(opens the news site in a new tab)
The Irrigation Department has issued a minor flood warning for low-lying areas of the Kalu Ganga Basin in the Ratnapura…

Towns that depend on this gauge

Flood help & emergency numbers

Common questions

Is Ellagawa flooding now?: As of Tue, 27 Oct, 12:05 am (Sri Lanka time), the Kalu Ganga at Ellagawa was 31.8 ft, close to the 32.8 ft alert level, and rising.
Will the Kalu Ganga at Ellagawa rise in the next hour?: In the next hour the Kalu Ganga at Ellagawa could rise to about 32.0 ft (31.8–32.2 ft). This is a forecast from the recent trend, the gauges upstream and rain, not an official warning.
What is the flood level at Ellagawa?: The official marks for this gauge are alert 32.8 ft, minor flood 35.1 ft, major flood 40.0 ft. Alert means the river has reached the alert mark: move valuables up and charge your phone. Minor flood means water is spilling over low ground, and major flood means move to safety.
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.

Official warning:

Irrigation Department

Reading at 12:05 am · 51 min ago

Normal

31.8 ft

Near alert: 1.0 ft below the alert mark, rising

Next hour

Rising slowly

Next 24 hours

Could reach alert level in ~8 hours

Likely to reach alert level around 8 am this morning (in about 7 hours) (about 70% chance).

Details

Likely to reach alert level around 8 am this morning (in about 7 hours) (about 70% chance).

Published as 9.70 m (alert 10.0 m, minor flood 10.7 m, major flood 12.2 m)

Elevated river-flow outlook this week.

In	Level	80% range	At
1h	32.0 ft	31.8 to 32.2	1:05 am
3h	32.2 ft	31.8 to 32.8	3:05 am
6h	32.6 ft	31.6 to 33.6	6:05 am
12h	32.8 ft	31.4 to 36.2	12:05 pm
24h	33.7 ft	29.0 to 41.4	12:05 am

Alert (32.8 ft): likely, about 7 in 10, from about 8:05 am
Minor flood (35.1 ft): possible, about 5 in 10, from about 11:05 am
Major flood (40.0 ft): unlikely, about 2 in 10

Local trend

+0.3 ft/h

Upstream avg

+0.1 ft/h

Rain that fell: 0.0 mm in the last 3 hours, 99 mm in the last 24 hours at this gauge (heavy rain)
Rain forecast: 27 mm in the next 24 hours over the catchment (moderate rain). Forecast model estimate.

Rathnapura 1.4mm

· Outlook: the GloFAS global flood model has river flow at 461 m3/s in its highest member within 7 days, above the 1-in-20 level (285 m3/s). This is a heads-up only; it does not change the levels above.
· Part of the range is above the highest level this model has seen (25.5 ft); treat it as a rough guide.
· Some rain is forecast over the catchment: about 27 mm in the next 24 hours (ensemble range 8 to 37 mm).

How this is worked out
· Latest level at Ellagawa and recent change, plus upstream gauges: Rathnapura.
· Forecast model estimate of catchment rain (Open-Meteo, area average over 9 grid cells above Ellagawa): 55 mm modelled for the last 24 hours, 27 mm forecast for the next 24 hours, with ECMWF ensemble spread.
· The 1, 3, 6, 12, 24 hour steps use this gauge's own recent changes and the other gauges on the river (fitted to about 11 months of hourly readings, including the November 2025 Ditwah floods); where this was tested against 'level stays the same' it missed by less.
· The 24 hour steps read the rain the satellite measured over Ellagawa's catchment (JAXA GSMaP, corrected for how it reads here), with rain beside the gauge and rain on the channels upstream timed separately (about 9 h from beside the gauge, about 8 h from upstream). Tested storm by storm it was closer than the version that reads the weather model's rain.
· Heavy rain upstream is part of the 12, 24 hour steps: rain that has fallen or is forecast over the catchment above Ellagawa raises the level, and the top of the range allows for the heavier forecast rain. Tested storm by storm (leaving each storm out, Ditwah included) it was closer than the river's own trend alone.