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Tim Foster gravatar image

Hi. I assume that the 3 pools are more settling than filtering ponds. I would suggest that the first step is to inspect these ponds and see if there are any obvious sources of Ecoli; perhaps they are seen as quiet places to openly defecate? These would need to be addressed before looking at chlorination. Turning to the reservoir is the water turbidity at entry and exit low enough for chlorination? If not, you may be wasting your time. Assuming satisfactory, is the reservoir covered or open? If the latter, you might have greater problems with any chlorine you dose being lost and the residual being unsatisfactory. I would suggest that you check the chlorine demand of the water coming into the reservoir and then do a one off dose of the reservoir and check that the residual is satisfactory. I suggest that you put this chlorine in at or near the water entry point and explore how to disperse over the tank and avoid short circuiting to the exit. If there is a lot of silt in the tank, this will absorb the chlorine if you disturb it. If you really cannot measure the amount of water, I would urge you to make an estimate by asking a representative number of families how much they take each day. You could then add the requisite amount of chlorine each day and test the residual each time as well. You could then adjust the daily dose to attain a satisfactory residual. Beware, if the water is heavily contaminated and you add a lot of chlorine, the taste might encourage people to drink less safe water.