Nalaka Gunawardene has published a piece in SciDev on the lessons from the floods/landslides. Nuwan Waidyanatha is in the Maldives at this moment advocating that they switch on cell broadcasting in the networks. In Sri Lanka, it’s on, but not used.
The Colombo-based ICT research organisation LIRNEasia has also been promoting the use of cell broadcasting for disaster communications. In this method, mobile networks can be used deliver text messages simultaneously to multiple users in a specified area. 
That telecom companies are willing to play their part was demonstrated when the largest network allowed subscribers to donate money to flood relief through a simple SMS. But only government agencies can issue disaster warnings and evacuation orders – which they did belatedly and patchily in this instance.
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LIRNEasia’s Samarajiva wrote in an analysis: “When citizens pay no heed to alerts, warnings and evacuation orders, the normal reaction is to blame the citizens or ponder the possibilities of forcible means. But what we learned through our research and from reflective practitioners is that people have good reasons not to act on warnings. So if we want to design effective messages, we have to start from the minds of the recipients. We must practice empathy.” 
Complexity in modern societies is why technological and bureaucratic solutions must be accompanied by sociologically sound approaches.