Implementation of modern automation systems on the northern gas fields located at the final stage of operation, is unprofitable economically and is not always possible technically. At the same time, the competent operation of such deposits requires constant monitoring for the state of gas wells and the shelves of the gas transmission network. In particular, the pressure and temperature is obligatory at the mouth of the well and at the end of the shelf. Also an important parameter from the point of view of regulating the modes of the wells is the instantaneous flow rate of the shelf, which is currently not measured at the old deposits. The article proposes to assess the Instantaneous consumption by an indirect method, according to the values of pressure and temperature. The algorithm for calculating the consumption is proposed, the testing of which at the Urengoy gas condensate field confirmed its adequacy. The monitoring system of technological parameters is built into gas fishery ACS. The algorithm visualization is implemented in the SCADA HMI / Cimplicity software package.