In irrigation, most of the water is transported by networks of open-channel irrigation systems (OCIS). In most cases, the OCIS are manually operated showing low efficiency. Then the incorporation of control strategies is one of the most practical ways to increase the efficiency of these systems. However, in order to design an appropriate control strategy, an accurate control-oriented model that can be used for analyses, simulation, design, and test of the OCIS under realistic scenarios is necessary. In OCIS, obtaining a control-oriented model is a challenge that has aroused interest in the related literature. In spite of the multiple research in modeling of OCIS, the development of control-oriented modeling approaches that describe the dynamic and nonlinear behaviors of OCIS with gate regulation structures, remains an open problem. In this paper, a modeling approach that describes the nonlinear and dynamical behaviors of OCIS using a mass and energy balance by channel is proposed, which is compared with two modeling approaches. The comparison has been performed with a test case proposed in the literature. The results show that the proposed modeling approach is better describing the nonlinear behavior of the OCIS and presents a simpler structure that can be used in the design and test of control, prediction, and estimation strategies for these type of systems.