The article is devoted to the study of the flow of the rivers of the metropolis of Almaty. Small rivers of Almaty attract more and more attention every year, as their water resources are widely used for household and drinking needs, irrigation, energy, and for other purposes. The health and well-being of the population depends on their water content. The article analyzes in detail the conditions for the formation of the water flow of rivers crossing the urbanized territory of Almaty, climatic characteristics affecting the flow. The description of the methodology and the results of calculating the characteristics of the average annual water flow and intra-annual flow distribution are given. Changes in the characteristics of river flow caused by climatic factors of recent decades are estimated.