The paper considers the questions of development of an environment monitoring systems in large settlements characterized by active traffic networks of various nature. The authors examine the purposes and objectives the fulfilment of which will allow us to go to a new level of the automated control over the level of man-induced impact on environment components. The article raises the pressing questions devoted to the development and application of modern systems of automated environment monitoring for particularly large settlements. Thus, on the example of the critical analysis of the working system of environment monitoring in Moscow, essential shortcomings of similar systems are revealed and the primary goals and directions of their required modernization are defined. The multi-agent technology of environmental mapping of the megalopolis, including mobile objects of land urban public transport, cars of large city taxi pools, carpool of car-sharing services is offered. In the conditions of the lack of necessary basic infrastructure, it is offered to apply self-organizing networks of data transmission. A general block diagram visually reflecting the features and interactions of the blocks of all structure is developed. The article presents the description of the architecture and features of the basic components of the implemented system.