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the recent past. As an example, a bank may have been moving rapidly in the past, <br />but has recently been heavily rip-rapped. At this point, the bank should be <br />considered stable because of the low erosion potential of its bank. Conversely, <br />even though a bank may be quite tall, steep, consist of sandy gravel, and, <br />therefore, have a very high erosion potential index; if the river has not migrated in <br />the last 35 years, then the bank should also be considered stable. An eroded bank <br />that has historically been moving should be considered unstable. <br />Therefore, in order to simultaneously address past stability history and present <br />condition at each bank location, the bank erosion potential index (maximum from <br />the left and right banks) was multiplied by the meander migration distance per <br />year to calculate a channel stability index for each segment of the river (about 0.1 <br />mile increments). This channel stability index -erodible bank height multiplied <br />by the annual meander distance - is analogous to a unit area of bank that can be <br />expected to erode each year. This index can be multiplied by its segment length to <br />give a very approximate estimate of sediment volume production of the bank <br />segment per year. <br />To calculate measures average channel stability for each sub-reach weighted <br />average, stability index values were calculated from the individual bank values. <br />For example, the channel stability index value for a segment was multiplied by <br />length and divided by the sub-reach length; then all the segments in a sub-reach <br />were added together to determine a weighted average value for the sub-reach". <br />The weighted average bank erosion potential, meander distance, and <br />channel stability index values for each sub-reach are shown in Table 1, <br />below: <br />Ike channel dank Erosion Bander Distan? <br /> aility Index (f t) (m /35 yr <br /> ? ?_??? <br />??ti <br />???, <br /> <br /> <br /> <br />Note :For the Stability Index, Zero is the best score <br />Riparian Habitat <br />Sub-reaches were given a total score of 0 to 30 to quantify the condition of the <br />existing riparian habitat resources. The total score is the sum of evaluation <br />measures in the following six categories: vegetation density, human activity, <br />agricultural disturbance, terrestrial habitat; and aquatic habitat. Scores for each <br />sub-reach in each category are displayed in Table 2 and scoring methods are