RFID could certainly be used for the applications you describe, but no company or government, to my knowledge, is currently looking at the technology for this use.
I do know that the U.S. military put out a contract for a company to develop an active RFID device that would float on water, connected to a sensor that could continuously monitor water supplies for three common waterborne pathogens: Vibrio cholerae (V. cholerae), Escherichia coli (E. coli) and Giardia intestinalis. The system would employ RFID to issue an alert if dangerously high levels are detected (see Protecting Water Supplies). I do not know if such a device was ever deployed.
It might be possible to deploy mesh networks of RFID-based sensors along coastlines, to provide an early-warning system if flood waters rise, though the cost of such sensors might be high. It might be cheaper to have hardwired or GPS-based sensors. But in the future, I think RFID-based mesh networks could be a low-cost way to provide this early warning to residents of flood-prone areas.
If any of our readers have heard of radio frequency identification being utilized in this way, please post information below.
—Mark Roberti, Editor, RFID Journal
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