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Home›Flood history›Mahaweli Ganga›Nawalapitiya

When does Nawalapitiya flood?

Flood warnings at Nawalapitiya come mostly between November and December.

Since 23 Nov 2025, this gauge has recorded flooding on 6 days and alert levels on 10 days. The most recent flood was 18 Sep – 20 Sep 2026 (major flood).

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 Nawalapitiya water level →

Live readings →

Flood warnings by day, one row per year

AlertMinor floodMajor floodEstimatedRecorded
NE monsoon
Inter-monsoon
SW monsoon
Inter-monsoon
JJanFFebMMarAAprMMayJJunJJulAAugSSepOOctNNovDDec
20264d
2025~1d
2024~10d
2023~39d
2022

Tap or hover a day for details. Earlier years are estimates.
Gauge records start 23 Nov 2025

When do flood warnings happen?

Share of days in each month with at least one gauge at alert or worse at Nawalapitiya.

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

Biggest flood events at Nawalapitiya

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

Year by year

Mahaweli Ganga at Nawalapitiya: about 11 affected days a year in gauge records since 23 Nov 2025.

Before 23 Nov 2025 there are no gauge records here; estimates suggest about 29 affected days a year in 2022–2024.

YearAffected daysMajor floodMinor floodAlertWorst day
2026(so far)Recorded
8
3
1
4
Major flood 3Minor flood 1Alert 4
Worst day: 3 Aug · major flood
2025Recorded from 23 Nov
6
2
1
3
Major flood 2Minor flood 1Alert 3
Worst day: 27 Nov · major flood
2024Estimated
24
3
7
14
Major flood 3Minor flood 7Alert 14
Worst day: 27 Nov · major flood (estimated)
2023Estimated
63
10
29
24
Major flood 10Minor flood 29Alert 24
Worst day: 21 Oct · major flood (estimated)
2022Estimated
0
–
–
–
Major flood 0Minor flood 0Alert 0
Worst day: No warnings

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.

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.

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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

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