Erosion monitoring along the Coosa River below Logan Martin Dam near Vincent, Alabama, using terrestrial light detection and ranging (T-LiDAR) technology

Abstract

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Erosion monitoring along selected bank locations of the Coosa River in Alabama using terrestrial light detection and ranging (T–lidar) technology, 2014–17

“…The Teledyne-Optech ILRIS High Density Enhanced Range laser scanner mounted on A, a tripod with the pan/tilt base; B, a survey boat; and C, the FARO Focus 3D X 130 laser scanner used in this study. a previous study at Logan Martin Dam, described in Kimbrow and Lee (2013). As described in the previous study (Kimbrow and Lee, 2013), T-lidar uses laser pulses that are sent from the instrument and reflected off objects within its field of view (FOV).…”

“…The study area included six survey sites on the Coosa River, consisting of two specific reach locations downstream from three selected dams: H Neely Henry Dam fig. 3) was the subject of the previous study (Kimbrow and Lee, 2013); site LM-108 is the upstream end of an island near the right bank ( fig. 3).…”

“…Survey methods used to obtain tripod-mounted T-lidar data were similar to those described in Kimbrow and Lee (2013). A surveying methodology was used with the intent of one-sided coverage of features in the ROI.…”

“…Discharges below these reservoirs are primarily controlled by power generation at the dams, and there has been an ongoing concern about the stability of selected stream banks downstream from the dams (Kimbrow and Lee, 2013). As part of Federal Energy Regulatory Commission relicensure of the Coosa River project in the early 2000s, the Alabama Power Company and various stakeholders identified particular areas of concern and wanted to take steps to monitor and document the extent of erosion.…”