The results of a three year study of the viruses isolated from sewage by means of five tissue culture types are reported. The enteroviruses identified demonstrated a seasonal pattern which was similar to that of clinical isolates. Echoviruses and coxsackieviruses displayed a changing pattern of dominant serotypes in both sewage and clinical isolates; echovirus 6, 19, 3 and coxsackievirus B4, B5, A9 successively became the most common serotypes. The poliovirus in sewage was all vaccine-like in character. Reovirus, type 2 was abundant; adenovirus, of several serotypes, were the least often identified.