Laserfiche WebLink
<br />. . <br /> <br />Glen Canyon and Lee's Ferry: Oct. 7-10 <br />Grand Canyon: Oct. 8-11 <br />Diamond Creek: Oct. 9-12 <br /> <br />Requirements: <br />Permission from NPS for installation of cables and <br />cars, data collection platforms, and stage discharge <br />recorders. <br />Permission from NPS for water sampling for bedload and <br />other purposes. <br />Placement of sufficient personnel and equipment, and <br />intergroup communication ability. <br /> <br />Beach Dunamics <br /> <br />Objectives: <br />Determination of the processes that move beach sediment <br />on a dial basis. <br /> <br />Determination of the changes in bank storage water <br />levels and chemistry of bank storage water. <br /> <br />Justification: <br />Beaches in Grand Canyon have gradually been reduced in <br />size during the period follow~ng initiation of Glen <br />Canyon Dam. This has been supported by comparison of <br />aerial photos; however, the processes that influence <br />this gradual degradation have not been accurately <br />evaluated, especially on a short term basis. Changes <br />of flows from low fluctuating to constant and back to <br />fluctuating creates a good opportunity to determine the <br />differential influences of fluctuating and constant <br />flows on beach degradation. A constant flow of 5000 <br />cfs, bordered by fluctuating flows, will also allow <br />evaluation of the movement of bank storage water. <br />Determination of water levels in the beaches will <br />permit water sampling and therefore analysis of bank <br />storage water chemistry. This will be useful in <br />determining the relative role of bank storage water in <br />the chemistry of eddies and the mainstem Colorado. <br /> <br />Methods: <br />Two or three beaches (tied to the beach survey) will be <br />selected for measurements. <br /> <br />Beach aggradation/degradation processes on a daily <br />basis will be measured with detailed surveying (more <br />measurement transects than the beach survey) and <br />pOSSibly time-lapse photography. <br /> <br />Changes in bank storage water levels and water <br /> <br />'i <br />