Catchment Characterisation and Source Water Quality

ion well The potential for pathogens from human and animal wastes that are present in the vicinity of wells to contaminate drinking water need special attention. The well construction itself may promote faecal contamination of the aquifer. As the well punctures all layers in the soil above the aquifer, animal droppings or human wastes that are deposited close to the well may travel with percolating rain water directly into the well if the wellhead is not properly protected. Or they may travel along the well wall or in the material surrounding the well in the drill-hole. 4.3 Transport and survival For most faecal pathogens, water is a transmission vehicle rather than a source of pathogens. Most of the enteric pathogens that are discharged into the environment are not able to multiply and need to survive until they are ingested by a suitable human or animal host. This is especially true for obligate parasites, such as the enteric viruses and protozoa like Cryptosporidium sp. and Giardia