A Forest Service crew spent the spring and summer of 2000 wading creeks as part of a project to inventory and map geomorphologic characteristics of Hoosier National Forest streams. The project was considered an initial step in the development of an aquatic ecological classification system for the Hoosier National Forest, following guidance in the Forest Service's A Hierarchical Framework of Aquatic Ecological Units in North America (Nearctic Zone) (Maxwell et al. 1995).

The Forest Service chose to classify stream reaches using a classification system developed by Dave Rosgen (Rosgen 1994; 1996). The stream crew measured such things as the bank full width and bank full maximum depth, the flood-prone area, sinuosity, and slope of the channel. They also determined the substrate composition by measuring pebbles along a transect line. All of these parameters were then used to classify the stream reach.

Stream reach classification can be a useful tool for Forest managers. Knowing your channel type can help you understand how the channel may respond to added amounts of sediment, or how it may respond to a fish habitat improvement project. Collection of the geomorphologic parameters can be used to study changes in the channel over time, a useful monitoring tool.

	Mike Casper and Jared Livingston record velocity measurements across the channel.  These measurements are used to calculate stream discharge.
	A modified Wolman pebble count was conducted at each channel cross-section to determine the dominant substrate particle size.  Mike Casper and Jared Livingston measure the intermediate axis of the pebbles.  Jennifer Alley ensures a minimum of 100 pebbles are measured and recorded.
	A survey rod and level are used to measure the channel cross-section. Measurements are taken at the floodprone area, top of bank, bankfull, edge of water, maximum depth, and many points in between. From this, the entrenchment ratio and width/depth ratio are calculated.
	Sinuosity, or the meandering pattern, of the stream reach is a key component of the classification system.
	After all measurements are made and numbers are crunched, a stream reach can be classified.

For Further Reading:

Maxwell, J. R., C. J. Edwards, M. E. Jensen, S. J. Paustian, H. Parrott, and D. M. Hill. 1995. A hierarchical framework of aquatic ecological units in North America (Nearctic Zone). USDA Forest Service, North Central Forest Experiment Station, General Technical Report NC-176.

Rosgen, D. L. 1994. A classification of natural rivers. Cantena 22: 169-199

Rosgen, D. 1996. Applied River Morphology. Wildland Hydrology, Pagosa Springs, Colorado.

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For more information, contact us at r9 hoosier website@fs.fed.us