Channel Geomorphology and In-Channel Veg Response to RFP

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I.d. Bank Material Survey The bank material survey will be performed as stated in the DMP. Measuring the properties of the bank material at only the pure panel Anchor Points (20 Left Bank/20 Right Bank) is probably sufFicient to characterize this component over the length of the 95 mile reach. The exact location of each bank survey will be recorded. After using a shovel to shave the bank vertically, difference in color or texture of sediment will be used to separate different layers or strata within the bank. Hand drawn maps describing the dimension and properties of the layers will be made and sediment samples using a steel cylinder sampler will be taken from each layer for grain size analysis. See grain size analysis (Section I.f.) for description of laboratory procedures. I.e. Bed and Bar Material Surveys The bed and bar material sampling will be performed as stated in the DMP. Grab samples will be made using a steel cylinder sampler at eighteen locations per Anchor Point (12 in main channel, 3 in secondary channel, and 3 on a bar) and exact sample locations will be recorded. Grain size analysis will be performed in the laboratory for each individual sample. See grain size analysis (Section I.f.) for description of laboratory procedures. I.f. Grain Size Analysis The procedure for grain size analysis for all sediment samples is generally the same. Samples are dried in an oven, placed and a stack sieves (%z phi increments), mechanically agitated with a RoTap sieve shaker. Each fraction captured on sieves larger than 2.83 mm is weighed on a precision balance. Fractions passing the 2.83 mm sieve are first burned in a muffle furnace to remove the organic component, and then they are placed in a sieve stack, mechanically agitated with a RoTap sieve shaker, and each fraction is weighted on a precision balance. Large volume samples may be split using a riffle splitter before burning to make the sample more manageable. Cumulative particle size distributions are plotted for each sample and specific cumulative percentiles calculated. I generally report the D15, D35, D50, D84, D95, and D100 (largest particle captured or largest sieved passed) for each sample but these "D" sizes can be adjusted if necessary to be compatible with prior work (e.g. some researchers use the D16). There is only one mention of using a certified lab for grain size analysis in the DMP (pg 12) and that is under the Bed Material Sampling Methods for Grain Size. Since there is no mention of this in the other sediment grain size analysis sections I am assuming this is a relic of an earlier draft of the DMP and not a requirement. As someone who has setup 3 different sediment labs (both bulk and suspended), I can tell you that using a certified lab would dramatically increase the cost of this study and add little, if any value to the results produced in this monitoring effort. II. In-Channel Vegetation Monitoring Il.a. Bar Transect Surveys Bar transect surveys will occur on all exposed areas without permanent woody vegetation within a 300 m belt transect at each of the rotating panel Anchor Points (5 surveys/year, each rotating panel Anchor Point is measured 3 times in the First Increment). Bar transects will be performed using a survey-grade GPS RTK system to document elevation and areal extent of non-vegetated and vegetated bars occupied by certain species of interest (young willows and cottonwoods, tamarisk, Russian olive, purple loosestrife, false indigo, and phragmites). A transect along the longest axis (A axis) of each bar will be surveyed identifying the various geomorphic and vegetative features present. A second transect (B axis), which is the longest transect perpendicular to the A axis, will be surveyed in a like manner. Similar to the cross section surveys, we can traverse a straight line between two points, without actually PRRIP - Geomorphic Monitoring 5 of 20 Blue Mountain Consultants