Treating water by putting it in 2 liter cola bottles and setting it in the sun on a black surface for 5 hours kills 99% of pathogens. One of the world’s truly great ideas (and currently highest ranked idea overall on Good Ideas). See http://www.sodis.ch/
The Solar Water Disinfecting Tarpaulin (SWDT) combines easy transport of water with solar purification. A Metropolis Magazine winning idea 2008. http://bit.ly/4tpQvv
Tata Consultancy Services in India has invented a cheap, effective water filter employing rice husks. Economist Magazine. http://bit.ly/9pcaVx
Dean Kamen’s latest quest: a box which burns cow manure to purify water. Forbes http://bit.ly/cPgxO0
A South Africa water quality testing system, “Aquatest”, decentralizes water testing by distributing tools for testing and gathering data by SMS. http://bit.ly/bhgWi1
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