The paper presents a brief summary of the research and implementation works carried out by the authors in three research projects in years 2005-2011 within one of the companies managing water supply system. Exploitation and diagnostic specificity of the operation of water supply systems was discussed. Opportunities and needs of supporting the exploitation and diagnosis of the water supply system, and the capabilities and needs of a computer-aided maintenance in this task area are discussed. Based on our recognition and analysis, two computer subsystems were presented, which are main parts of an Integrated System for Control And Management of Exploitation of the Water Supply System. In this regard, there was presented a key model aspects that unde rpin the construction of subsystems, and it was discussed how the system works in the context of supporting selected tasks carried out by the technical staff of the analyzed company.