Abstract This paper is concerned with the major issues considered to be important for successful application of computational fluid dynamics to environmental flows. Among the issues of primary concern in the present paper are meshing and turbulence modeling. As regards meshing, we propose an approach that employs unstructured meshes in conjunction with solution-adaptive mesh refinement. Examples are presented to illustrate the efficacy of the unstructured mesh-based approach. The issue of turbulence modeling is discussed at length, inasmuch as turbulence modeling determines the fidelity of computational results for environmental applications. Emphasis is laid upon the capability of engineering turbulence models to capture the salient features of environmental flows such as atmospheric boundary layer over a smooth terrain and flows around bluff bodies.