Author
Bennett, Sean |
Submitted to: Transactions of the ASAE
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/1/2002 Publication Date: 4/1/2003 Citation: BENNETT, S.J., DUNBAR, J.A. PHYSICAL AND STRATIGRAPHIC CHARACTERISTICS OF SEDIMENTS IMPOUNDED WITHIN FLOOD CONTROL RESERVOIRS, OKLAHOMA. TRANSACTIONS OF THE AMERICAN SOCIETY OF AGRICULTURAL ENGINEERS. 2003. V. 46. P. 269-277. Interpretive Summary: Since 1948, the USDA-NRCS has constructed over 10,000 upstream flood control dams across the U.S., and many of the reservoirs are filling with sediment. To rehabilitate these structures, the sediment impounded by these dams must be assessed in terms of the structure's efficiency to regulate floodwaters and the potential hazard the sediment may pose if reintroduced into the environment. Continuous sediment cores were obtained at two flood control reservoirs in Oklahoma. Analyses of the sediment within these cores showed that silt and clay sized sediments dominate the deposit within each reservoir pool, and these size fractions were associated with relatively higher concentrations of organic carbon and nitrogen. Sediment deposited within the reservoir after construction was discriminated from sediment present before construction. The rates of sedimentation were determined for each reservoir, and the timelines could be extended across the reservoir. Vibracoring is shown to be an effective technique in the assessment of sedimentation issues necessary for flood control reservoir management. This information will be useful to the USDA-NRCS in their evaluation of the several thousand USDA-NRCS flood control dams. Technical Abstract: Since 1948, the USDA-NRCS has constructed over 10,000 upstream flood control dams across the U.S., and many of the reservoirs are filling with sediment. To rehabilitate these structures, the sediment impounded by these dams must be assessed in terms of the structure's efficiency to regulate floodwaters and the potential hazard the sediment may pose if reintroduced into the environment. Continuous sediment cores were obtained at two flood control reservoirs in Oklahoma. Stratigraphic analyses showed that silt and clay sized sediments dominate the deposit within each reservoir pool, and these size fractions were associated with relatively higher concentrations of organic carbon and nitrogen. Pre-construction sediment was discriminated from post-construction deposition, rates of sedimentation were determined, and stratigraphic correlation of both sediment units and timelines across the reservoir was possible. Vibracoring is shown to be an effective technique in the assessment of sedimentation issues necessary for flood control reservoir management. |