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<br />. FEE 05 '3C <br /> <br />- :c: <br /> <br />= . <br /> <br />based on eddy models, it time permits, and channel <br />topoqraphy, and channel and eddy sediment storage determined <br />trom a.rial photographs taken during a very low constant <br />discharge period (e.g., 1000 cfs) when the river is low in <br />suspended sediment (e.g., April/Hay or October). Short-term <br />changes in beach surface topography will need to be measured <br />under normal operations discharges, as well as controlled <br />fluctuating discharges and non-fluctuating discharges. <br /> <br />In order to create response curve., these research <br />discharqes will include both constant and fluctuating <br />discharges. There will be five constant discharge regimes <br />and seven fluctuating discharges. Fluctuating discharges <br />will be both low/medium fluctuations and high fluctuations. <br />The low/medium fluctuations will have low, medium and high <br />minimum discharges, while the high fluctuations will have <br />low and high minimum discharges. The high fluctuating <br />discharge. will also have high and low up ramp and down ramp <br />rates. Following each research discharge epis)de (10-11 <br />days), a 3-4 day periOd ot relatively low constant discharge <br />(ca. 3000 cts) is needed to evaluate the etfects on beaChes, <br />larval fish in backwaters, etc. Because of bank storaqe and <br />time to equilibrium of the system, teats will not be made <br />for a few days after atarting a research flow, especially <br />those with low minima. The etfects of bank stored water <br />discharge on beach erosion will be testQd with multiple <br />piezometers (wells) in several beaches as done during the <br />October 1989 5000 cfs constant discharge study. <br /> <br />The tollowing are secondary hypotheses to be tested under <br />the research program tor testing the above primary hypoth.sis. <br />The.. are simplitied hypothe.es which do not recognize the <br />potential interaction between the various discharge parameters. <br /> <br />a.-l.la. There is no relationship between the magnitude of <br />daily discharge fluctuations and beach degradation or <br />aggradation. <br /> <br />a.-l.lp. Erosion ot old high water deposits is not <br />influenced by the magnitude ot daily discharge fluctuations. <br /> <br />a.-l.le. There is no relationship between the magnitUde of <br />daily minimum discharges and beach degradation and aggradation. <br /> <br />H.-l.ld. There is no relationship between the rate of <br />increasing daily discharges (up ramp) and beach degradation or <br />aggradation. <br /> <br />a.-I. Ie. There is no relationship between the rate of <br />decreasing daily discharges (down ramp) and beach degradation or <br />aqgradation. <br /> <br />3 <br />