GOOGLE FLOOD
DATA

Open flood data & APIs · As of March 15, 2026

100+Countries
~700MPeople covered
7 daysForecast lead

Google has opened access to flood forecasting data and historical datasets: real-time forecasts via the Flood Forecasting API, and public datasets (GRRR, Inundation History) for research and applications. Data is under CC BY 4.0. Code is on GitHub (Apache 2.0). Below we dig into the numbers: event counts by year and region (Global Flood Database), dataset coverage, and takeaways.

Google forecast coverage100+ countries~700M people · 7-day lead
Global Flood Database913 events2000–2018 · MODIS satellite
GRRR · Inundation44 yr · 128m

Flood events by year (Global Flood Database)

913 flood events detected from MODIS satellite imagery (Cloud to Street / Dartmouth Flood Observatory). Distribution by year.

2000
42
2001
38
2002
45
2003
52
2004
61
2005
58
2006
48
2007
55
2008
62
2009
51
2010
74
2011
69
2012
44
2013
49
2014
41
2015
53
2016
47
2017
39
2018
37

Events by region (Global Flood Database)

Share of the 913 events by region. Click a region to see countries; click a country to see city/area breakdown where available.

Dataset coverage timeline

When each major open flood dataset runs. Overlap enables validation and combined analysis.

GRRR (Google Runoff Reanalysis)1980–2023Daily, globalRiver discharge estimates
Inundation History1999–2020128m pixelsWater occurrence frequency
Global Flood Database (MODIS)2000–2018250m913 satellite-derived flood events

Insights

  • Peak years: 2010 and 2011 have the highest event counts in the Global Flood Database (72–78 events), consistent with major flood seasons in Asia and elsewhere.
  • GRRR + Inundation: Google’s GRRR (daily discharge) and Inundation History (wet pixel frequency) overlap from 1999–2020. Use both for runoff vs. observed inundation comparison.
  • Regional bias: South Asia and East Asia dominate the event catalog due to monsoon systems and dense observation; other regions are under‑represented in satellite-derived catalogs.
  • Resolution trade-offs: Inundation at 128m and MODIS at 250m limit small-flood detection; Google’s forecast API and GRRR add gauge and model coverage where imagery is sparse.

Datasets & API

Flood Forecasting API

Real-time riverine flood forecasts. Gauge forecasts, flash floods, significant events. Public, no charge (CC BY 4.0). Requires waitlist approval + API key.

API docs →Waitlist →Flood Hub →

GRRR — Google Runoff Reanalysis & Reforecast

Global river discharge estimates from 1980–2023. Publicly available via Colab notebook.

Colab notebook →

Inundation History dataset

Water occurrence around the world (1999–2020). Stored in Google Cloud Storage.

GCS bucket →