Disclaimer: This content is for example purposes only, created during the G20 DRR Hackathon by Team MapleByte. A full disclaimer is provided in the footer.
In communities with limited digital access, bells, sirens, or alarms connected to the power grid (or backup generators) can deliver flood warnings effectively. These systems are highly inclusive, reaching people without phones or radios.
This method is important because it provides a reliable and immediate warning that does not depend on literacy, connectivity, or network coverage. However, maintenance and testing are critical to ensure reliability when floods strike.
How to Put This Into Practice
Install sirens or loudspeakers in central community areas.
Connect alarms to both grid power and backup batteries.
Establish testing schedules to maintain trust in the system.
Train communities on what different alarm signals mean.
Example
Japan’s municipalities operate community-wide siren systems tested monthly. When floods or tsunamis threaten, these alarms quickly alert even residents without digital devices, ensuring mass coverage.