The paper presents the methodology to develop an information and control system to monitor the technical state of power lines. The relevance of the topic is due to the need to improve the reliability and safety of power systems in the context of the growing requirements to power quality. The key stages of information and control system development are described, including requirements definition, architecture design, technology selection and testing. Special attention is paid to the use of modern technologies, big data processing to create a system capable of promptly responding to changes in the state of power lines. Data visualisation, integration of different technologies and cyber security are also addressed. The paper emphasises the importance of user training and support during the implementation phase of the system, as well as the prospects for further development of the system in the field of energy resource management.