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While emergency approaches rightly focus on biological contamination as the primary risk, if you are improving a water supply for a village long-term you also need to consider long term chronic risks. These can come from a wide range of chemicals in the water that simple portable tests kits will not detect.
If a laboratory is available then I would strongly recommend that route. As well as not having to invest money up front in equipment and reducing the risk of user error, a good laboratory will be able to test for more contaminants.
I would advise that you also engage a water quality expert to help you produce a water safety plan. You can read about these in the World Health Organisation's free-to-download Water Safety Plan Manual: https://www.who.int/water_sanitation_health/publication_9789241562638/en/ but an experienced advisor should be able to vastly simplify the process and focus on the specific needs of your village.