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<br />Depth of open interstitial space (depth to embeddedness) will be measured on a 5 or 10-ft grid over the <br />extend of the bar. Measurement will be made by working a hand between rocks until the fingers touch <br />the sand embedded depth, The depth of penetration below the average top of cobble immediately <br />adjacent to the sample point will he measured and recorded as the depth of open interstitial space. <br /> <br />Change in bar morphology will be determined by producing three-dimensional plots of the surveyed <br />surface and subtracting the resulting surface from the surface generated from the previous survey. The <br />amount of change will be correlated to the flow conditions for the year. <br /> <br />The size distribution of cobble at each bar is computed and the D16, Dso and D84 sizes reported and <br />compared to previous years. Depth of open interstitial space will be computed as actual depth and <br />multiples of mean cobble diameter. <br /> <br />4, Backwater Perturbation Monitoring: To characterize the relative quality of backwaters, five <br />representative backwaters within each geomorphic reach will be measured for water and sediment <br />depth. Measurements will bc made annually between September 15 and Nov 1 per the long term <br />monitoring plan. These sites will remain the same from year-to-year to the extent possible. If a <br />backwater is "lost," another will be selected for sampling and retained in the sampling regime until it is <br />lost. Depth of sediment will be measured and recorded for "lost" backwaters. All measurements will be <br />made at flows between 500 and 1,000 cfs, if possible, and at the same flow from year-to-year, if <br />possible. Sediment and water depths will be measured at three points in each backwater (mouth, 1/3 and <br />2/3 of length), The backwaters sampled will be marked on digital aerial imagery. <br /> <br />Storm events will be determined by changes in flow and turbidity at USGS gages located near Shiprock <br />and Montezuma Creek. <br /> <br />The annual report will include a summary of backwater measurement data for each site, including site <br />location, water and sediment depth, flow at sampling, flow and turbidity data. Every five years the <br />runoff/storm event/backwater habitat relationships will be analyzed, <br /> <br />Products: <br /> <br />An annual report and data files for inclusion in the GIS database will be produced under this task. The annual <br />report will include a summary of backwater measurement data for each site, including site location, water and <br />sediment depth, flow at sampling, flow and turbidity data. <br /> <br />22 <br />