So far my "research" has included sampling water at different sources (bore hole pumps and hand dug wells) and points of use (household clay pots) to test for bacteria. I'm using a very simple test medium (3M Petrifilm) which detects total coliforms and E. coli. To do a test you simply apply 1 ml of water onto the petrifilm, let it sit for 24 hours in a warm place, and then count the number of "dots" that show up on the film. Each red or blue dot indicates a CFU (colony forming unit), red for total coliform and blue for E. coli. Each CFU is typically made up of many, many individual bacteria cells.
In the US, the EPA water quality standard for municipal drinking water is 0 cfu/ml (ie. nothing!). We Americans have decided that the water coming out of the tap should be pathogen free. How nice.
The results for water in my village thus far are nothing to celebrate. I tested 3 pumps, 6 wells, and 45 household clay pots. Every single sample I took was contaminated except for two of the pumps. Most with a bacteria count over 100 cfu/ml. Many were over the detectable limit of the petrifilms.
The pictures below are of three different samples that were tested. "P4" is from one of the pumps. It's clean. No bugs to be found. "L2" is a well. Lots of nasties. "HL11" is a household clay pot. Bunches and bunches of yuckiness. The two contaminated films both have over 400 cfu/ml.
If you're wondering why there are air bubbles on the contaminated slides... that's because the bacteria on those films have been gorging themselves on growth media and are now belching and farting out waste products all over the place. (Coliform bacteria aren't known to be the tidiest organisms, which is why we don't want them in our drinking water.)
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