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A simple two‐layer water circulation model is developed for the application in homogeneous coastal regions. The objective is to develop a two‐layer model with a relatively thin upper layer that can respond better than a depth‐averaged model to a changing wind field, hence give better predictions of the near‐surface velocity. The governing equations for each water layer are derived from depth averaging of the Navier‐Stokes equations. Coupling between the upper and lower water layers is through the mass and momentum transfer at the interface. To obtain the stress‐transfer function at the interface, the problem of wind‐driven circulations in finite water depth is solved with a bilinear eddy viscosity model that assumes the vertical eddy viscosity to increase linearly with the distance from both the water surface and the bottom boundary. It is found that the stresses at the interface, τi, can be related to the mean flows, above and below the interface, V1 and V2, by a simple constitutive law, τi = 0.18 ρ u*s (V1 ‐ V2) where ρ is the water density and u*s is the shear velocity at the water surface. Comparisons of the two‐layer circulation model with commonly used depth‐averaged models for the prediction of coastal circulation reveal that the use of the two‐layer model gives more realistic predictions of the water motion. As an example, the upper water layer of the two‐layer model is coupled with that of an ice circulation model and it is found that the coupled ice‐water circulation model gives accurate predictions of ice floe movements obtained from field measurements.