The Grand River runs through central and southern Ontario and is known world wide for its diverse fisheries. From the brown trout in the head waters to its walleye, rainbows and catfish in the tail waters anglers come from far and wide to enjoy its incredible angling. However there has been no standard data collection on the Grand River. This study was to use a new protocol to collect baseline data and take a first look at the effects of barriers and habitat fragmentation. The non-wadeable stream protocol was first conducted on the Grand River in 2000. This protocol (developed by Carl et al. unpublished) was used on two rivers in 2000 The Grand and the Trent River. In 2001 it was continued on both the Trent and Grand River and was started on the Petawawa River system. The Trent River system is highly fragmented with dams and locks and has an extensive set of reservoirs upstream of the study area that are used to stabilize flow. Comparatively the Grand River has only five dams located in its study area, and large sections of riverine habitat. Our objective is to quantify fish community structure and stressors that act on communities in order to build a model of how riverine ecosystems work. By taking a comparative approach at several hierarchical scales, this study will establish explicit links between barriers and their effects on aquatic communities, species and metapopulations. The purpose of this project is to provide baseline data on fish community and habitat in the Grand River from Cambridge downstream to Dunnville. In the future the results of this study will be compared with other rivers systems to investigate the effects of dams and locks. Sampling on the Grand River will also help develop and strengthen the methodology for sampling fish communities and habitat in non-wadeable rivers.