Four urban water resource case studies are employed as a means for elucidating causation inferences on the process of technological innovation: San Francisco master plan; Chicago underflow plan; land disposal of wastewater; and pressure wastewater sewer systems. All four are instances where innovation concepts have been successfully applied, and they are all concerned with water quality matters. Consideration is given to industrial parallels, the roles of individuals versus groups in innovation, and certain characteristics of some leading innovative local government administrators. Also taken into account are related subjects of technology transfer and public technology.