8106

• UCREFRP Catalog Number: 8106
• Author: Anderson, R. M.
• Title: Riverine Fish-Flow Investigations.
• USFW Year: 1998.
• USFW - Doc Type: Fort Collins, Colorado.
• Copyright Material: NO

DEFINITIONS OF HABITAT VARIABLES

Seven flow and/or channel parameters were computed by the hydraulic equation

for each riffle cross section. Each strata was characterized by determining the mean and

variance of the seven parameters for all its riffle cross sections. Strata were compared to

each other by statistically testing for difference between the means of the seven

parameters to identify and group strata with similar attributes. The seven parameters and

bankfull flow are defined as:

a) Top width: width of the stream at the water surface.

b) Percent wetted perimeter: The distance along the stream bed in contact with

the water divided by the distance along the stream bed between the grassline
of each bank.

c) Depth: The vertical distance between the water surface and some point on

the streambed.

d) Rise in stage: The difference in the vertical distance from the water surface

elevation at a flow of 1 cfs to the water surface elevation at a higher flow.

e) Width/depth ratio: A unitless index of cross-sectional shape, where top width

is divided by average depth.

f) Cross Sectional Area: Wetted area in square feet determined by multiplying

stream width times average depth.

g) Velocity: Distance water moves per second.

h) Bankfull stage: Discharge at which channel maintenance is the most effective,

that is, the discharge at which moving sediment, forming or removing bars,

forming or changing bends and meanders, and generally doing work that

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