MesoHABSIM builds upon pre-existing physical habitat simulation models (e.g. PHABSIM) which is an essential component of the United States government's methods for establishing minimum stream flow requirements. 
MesoHABSIM is an augmentation of this system, designed during a restoration study of the Quinebaug River. The changing spatial distributions of physical attributes of a river as a result of variations in flow and the biological responses of aquatic species to these changes, provide the basis for simulating the consequences of ecosystem alteration, and consequently the justification of restoration measures. MesoHABSIM modifies the data acquisition technique and analytical approach of similar models by changing the scale of resolution from micro- to meso-scales. Due to this increase in scale, the model takes variations in stream morphology along the river into account and allows for application in larger-scale projects.