A sample of 68 wells left again in the four districts of the City of Basoko had been the subject of our investigations for the analyses physicochemical and bacteriological. Also an investigation in the 350 households into the behavior of the house holds screw-with screw of water of domestic use was carried out. The bacteriological analyses raised the presence of the indicator germs of the pollution in analyzed water of the wells, like some pathogenic, whose quantitative average of the colonies is 79,05; 443,39 and 3, 22 units by water 100ml, respectively for the fecal coliformes, streptocoques fecal and Salmonella or Shigella. This observation shows that all the investigués wells are polluted. The identified germs, in addition to the Salmonellas or Shigella, are: C. frendi (33,8%); E coli (26,7%); Klebsiella spp (18, 3%); C intermédiare (12,7%) and Enterobacter (8,5%). As for the chemical physico analyses, the pH of water of well takes varies from 4,92 to 7,38; while their temperature ranges between 25 and 33° C the average values of the proportioned chemical compounds are: 8,635 mg/l for the ions chlorides; 13,225 mg/l for calcium; 8,02 mg/l for magnesium; and that the alkalinity of water of the wells analyzed was 85,6 Mg / L. It comes out from our investigations that certain households draw and store water in the buckets without lids, (42, 23%); others clean their containers of storage or drawing up that once per week (3,33%). Moreover, it ya of the households which preserve water of domestic use during in the month 3jours (5,78%). 88,22% of the households do not treat water before consumption. In addition, certain households do not have toilets, it is - with - to say défèquent with the free air (10,44%); and that 9,55% of the wells of supply water are located at less than 50 meters of the toilet.