Water system Monitoring: counting the bugs

Students at the Portobelo Colegio, together with Dr. Amador Goodridge, have been monitoring coliform bacteria in their drinking water system using donated test kits. Their results show that while bacterial levels are quite high in the source stream (D) and in the first storage tank (C), filtration (B), but especially chlorination (A), significantly reduce the bacterial concentrations to almost nothing.

It seems like bacteria actually grow better in the storage tank, probably because it's warmer than the stream, but filtration and chlorination together are quite effective at treating the water. While it's difficult to assess other pathogens, coliform bacteria help us estimate the over all effect the installed water treatment system is having at the colegio.

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