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G20 DRR Hackathon Microsite for Policy Makers

Can an early warning system be established?

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.

Early warning systems (EWS) are critical tools for saving lives in flood-prone areas. They provide residents with time to act before floodwaters arrive. For government officials, the central question is not whether warnings are valuable, but whether reliable systems can be designed, funded, and maintained in marginalized or informal settlements.

This assessment involves both technical and social factors. On the technical side, EWS may require river gauges, rainfall sensors, mobile communication systems, or community sirens. On the social side, residents need to understand and trust the alerts, and mechanisms must exist to ensure the most vulnerable populations receive warnings.

How to Put This Into Practice

  • Conduct feasibility studies on local communication infrastructure (mobile coverage, radio, power supply).
  • Evaluate partnerships with NGOs, telecom providers, and local municipalities to co-fund and maintain systems.
  • Design tiered systems: for example, cell phone alerts in areas with coverage, and loudspeaker/bell alarms where digital infrastructure is absent.
  • Establish protocols for testing, training, and regular community drills.
  • Can invest and assist in the creation of peer-to-peer phone networks, mesh networks, and/or upgrade cell towers to ensure the infrastructure has capacity to handle phone alerts.
  • Repurpose the existing, or begin expanding, the power-grid inside informal communities to have bells or alarms that warn of imminent flooding.
  • Ensure these warnings include actionable language that identifies safe areas for residents to rally.
  • Phone alerts need to consider accessibility and literacy considerations.

Example

In one coastal city, the government invested in a hybrid EWS. Households with mobile phones received SMS alerts, while communities without coverage relied on church bells powered by backup batteries. This layered system ensured warnings reached all demographics, reducing fatalities in subsequent floods.