In order to research on the application of nano-concrete to reduce roughness coefficient, and considering that roughness coefficient and calculating it are fundamental issues in hydraulic engineering. Also, analyzing the correct evaluation of flow rate and interaction with other hydraulic parameters such as velocity, shape and type of section, and flow pattern, is one of the most important problems in fluid mechanics, and considering that the possibility of minimizing roughness on designing of hydraulic structures and irrigation networks in order to increase velocity and then the flow rate at different sections, are subjects which have been noted by researches and industrial entrepreneurs since years ago. the author of the article had done a series of experiments, the effects of using silicate nano-particles in the floor coating of the channels have been studied in a hydraulic laboratory flume. Through this experimental research, we could had known that adding Nano-Silicate to the concrete mixture will cause the active SiO2 to mix with the free calcium hydroxide available in the micro holes of the concrete and produce unsolved calcium silicate, and eventually cause the structure of the cement to become more dense and become less penetrable causing the concrete to be more resistant. By using this product, we can produce smooth and homogenous surfaces in the upper surface that can increase the flow rate and velocity of fluid in channels, clarifiers and crests of dams.