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WEST recommendation on the best method to adjust water surface elevation (WSE) to the time <br />of crane group use. <br />11/27/2007 <br />This recommendation is based on the report by Lisa Fotherby "Summary of Phase I <br />The whooping crane protocol lists three parameters to be obtained from the profile data: depth, <br />wetted width, and sandbar elevation. These parameters are directly influenced by the change in <br />water surface elevation between the time of use and time of measurement of the profile data. <br />HECRAS <br />The depth and wetted width parameters are easily output from the HECRAS model. Sandbar <br />elevation can be calculated using a linear interpolation program WEST has written in Matlab <br />using the change in water surface elevation output from the HECRAS model. <br />A disadvantage in using HECRAS will be in the constraints of the model output. The greatest <br />apotential constraint occurs with the estimation of wetted width. The whooping crane survey <br />protocol defines wetted width as the distance covered by water between obstructions greater than <br />1.5m along a line perpendicular to the channel flow and passing through the crane location. <br />HECRAS is based on a valley -wide cross section and the output is provided for each channel <br />within the valley -wide cross section. Our measured profiles only extend from obstruction <br />(objects (e.g., vegetation, bank, etc.) greater than 1.5m above water line) to obstruction. In the <br />case of multiple channels it is likely that the width estimate output from HECRAS would be <br />larger than our measured distance between obstructions, a deviation from the protocol. In this <br />case we will set the wetted width to the measured distance between obstructions. However, we <br />believe that this constraint is unlikely to impact the analysis and is justified by the benefits of <br />HECRAS. <br />• <br />Gage Method <br />With the gage method, after the water surface elevation differential is extracted from the gage <br />data, the calculation of depth and sandbar elevation on the adjusted data could be conducted <br />using a linear interpolation program WEST has written in Matlab. The calculation of wetted <br />width would require WEST to write an additional program based on a linear model. However, <br />the gage method would provide a reasonable estimate of channel characteristics if the sighting is <br />in a similar channel as the adjacent gage, but this is not likely for all or even most of the crane <br />WEST, Inc. Page 1 2/5/2008 <br />