The article elaborates the significance of water, which is necessary for the maintenance of an organism and specifies its daily needs in human beings. Reference data on the early isolations of viruses from sewage water and modern understanding on the occurring virus species are listed. The article considers virus survival in sewage and flowing water and other fresh and marine water systems as well as marine silt or fruit. Finally, we give here an overview of basic features of individual virus kinds that are potential water contaminants.