Bacteriological Quality of Rainwater in Roof and Ground Catchment Systems in Botswana

ABSTRACT

Bacteriological analyses were conducted on water samples from 13 roof tanks and 8 ground catchment tanks in Botswana in 1983. The results show that rainwater collected from corrugated iron roofs and stored in covered tanks is of high quality compared with traditional water sources and could provide a safe drinking water supply. The results for the ground catchment tanks, however, indicated that the water posed a serious health hazard. This is significant since several hundred ground tanks are already being used to provide water for other things besides human consumption. Since more ground tanks are planned both in Botswana and elsewhere in Africa the fencing of the catchment area and the use of simple sand and charcoal filters are recommended as the most practical means of insuring improved water quality in ground tanks.