Google Flood Hub — Bangladesh Water Development Board's AI-Powered River Flood Alert System

Bangladesh's Water Development Board (BWDB), the national hydrological agency, partnered with Google Research from 2020 to layer an AI/machine-learning flood-inundation model on top of BWDB's own gauge readings and forecasts, extending flood prediction into ungauged tributaries of the flood-prone Brahmaputra-Jamuna and Padma river systems. Localized warnings are pushed to residents through Google Search, Maps and Android notifications.

To provide flood early-warning alerts with a lead time of three hours to three days, including in remote basins that lack dense sensor networks.

Google's hybrid hydrologic-hydraulic ML model, described in a March 2024 Nature paper, is combined with BWDB's real-time gauge data and 5-day forecasts. The system expanded from a 2020 pilot covering 36 sub-districts in 14 districts to 55 districts and 99 sub-districts by the 2021 monsoon.

The 2020 pilot sent about 1 million notifications to roughly 300,000 Android users. Between 13-31 August 2021 alone the expanded system sent 2.9 million notifications to 1.5 million unique users, with a 3.5% click-through rate. The underlying model now operates in over 80 countries, reaching an estimated 460 million people globally (a global, not Bangladesh-specific, figure).

Google's own reporting acknowledges low Android penetration in the remote, flood-exposed areas the system most needs to reach, and describes ongoing work to extend alerts via SMS and IVR for feature-phone users. No independent, Bangladesh-specific accuracy evaluation of forecasts against observed flooding has been published.