Laserfiche WebLink
<br /> <br />UNITED STATES <br />DEPARTMENT OF THE INTERIOR <br /> <br />GEOLOGICAL SURVEY <br /> <br />?" :1; <br /> <br />. ~:_;:; ,:,-:r". " <br /> <br />GCMR-740 <br />ADM- 1.10 <br /> <br />MEMORANDUM <br /> <br />(12 27 0 3 <br /> <br />SUBJ: <br /> <br />Glen Canyon Dam Adaptive Management & Technical Workgroup <br />Representatives and Science Advisors <br /> <br />To! S. M,li,. lo"'",,"" s"i=, Pro,,= M=g~. SBSc, GCMltcf)j <br /> <br />Distribution of tARS Red Book article on use of LlSST for monitoring <br />suspended-sediment transport in the Colorado River Ecosystem beIow <br />GIen Canyon Dam <br /> <br />TO: <br /> <br />FROM: <br /> <br />The attached article, Testing laser-based sensors for continuous in-situ monitoring of <br />suspended sediment in the Colorado River, Arizona, by Melis et aI., has recently been <br />accepted for pubIication by the International Association for RydroIogicaI Sciences <br />(IAHS) within its Red Book series voIume entitled Erosion and Sediment Transport <br />Measurement in Rivers: Technological and Methodological Advances. <br /> <br />These tests have been carried out within the context of recent research efforts undertaken <br />as part of the ongoing suspended-sediment mass balance monitoring and research project. <br />The objective of these LlSST tests was to determine whether existing Iaser-based <br />instruments couId provide high-resoIution, real-time suspended-sediment transport data <br />from the CoIorado River related to diurnaI operations at Glen Canyon Dam. Such high <br />resolution data are criticaI to addressing issues. off me-sediment transport and <br />conservation reIative to hourly-to-daily changes in releases from the dam. <br /> <br />This report describes the initial test results obtained from the Laser In-Situ Scattering and <br />Transmissometry (LlSST) instruments in 2001 and 2002, while deployed at the Grand <br />Canyon suspended-sediment monitoring site near Phantom Ranch. On the basis of these <br />results and data from later tests, the LlSST instruments have been shown to provide a <br />critical roIe in continuous monitoring of suspended-sediment transport in the Colorado <br />River. Continuous monitoring may eventually prove to be of value in determining the <br />optimal duration of sand-bar building high flows released from Glen Canyon Dam under <br />varying sediment-supply conditions. <br /> <br />Please review this article and share it with your staff and other interested parties. Feel <br />free to contact me at (520) 556-7282, with any questions you have regarding these <br />findings, or the published conclusions derived from them. <br /> <br />02358 <br /> <br />