Manure-fired Clay Water Filter

One of the most serious problems facing developing nations and areas affected by natural disaster is the lack of potable water.

Tony Flynn, of The Australian National University, has developed an ultra-cheap, ultra-low-tech water filter capable of removing virtually all E. Coli bacteria from a water supply.

The filter can be made from terra cotta clay mixed with coffee grounds, molded into a cup-like shape, then fired in a manure-pile. The manure will burn at temperatures of up to 700????F, which will burn away the coffee ground inclusions. The resulting pores are large enough to allow water to pass, but small enough to trap bacteria and other pollutants.