Michigan Department of Natural ResourcesThis dataset identifies the physical channel units, termed "valley segments", that are based upon the concept of a natural ecological unit, as defined by the spatial scales of riverine physical and biological processes. Valley segments are fairly large units that are characterized by relatively homogenous hydrologic, limnologic, channel morphology, and riparian dynamics; valley segment characteristics change sharply at stream junctions, slope breaks, and boundaries of local landforms. Catchment size, hydrology, water chemistry, water temperature, valley character, channel character, and fish assemblages were the attributes used to interpret and describe the ecological character of river valley segments. A GIS was utilized to interpret the information from the catchment and valley characteristics and categorizations were developed for each component attribute and assigned category values for each segment. Results were stored in ArcView 3.0 format. This dataset on valley segment classifications provides an initial description of the river resources in the Lower and Upper Peninsula of Michigan. This dataset and its development are an iterative process in which validation of attribute codings and the addition of new attributes will continue.ArcGIS FeatureLayerhttps://hub.arcgis.com/datasets/baabf6f5ea1d4295864eff3c90ada513_3engState of Michigan Open Data PortalPublicFisheries River Classification - Institute for Fisheries Research (IFR) [Michigan]Web servicesMichiganLast Modified: 2026-01-06