Soil Erosion and Sediment Yield in the Panama Canal Basin, Panama.

Bc. Julián Eli Gutiérrez Hernández

Master's thesis

Abstract:

Soil erosion is a major issue in Panama because the frequency of rainfall promotes transport of soil from disposal sites into the canal channel. Increased erosion means the canal channel needs to be dredged more frequently to keep the channel operational, even now with the expansion of the Panama Canal. The Alhajuela Lake and Gatun Lake sub-basin, provides up to 40% and 60 % of the water necessary to operate the Panama Canal (Larsen and Albertin, 1984). However, excessive loads of sediments in the Panama Canal Basin sediments largely impact in the Alhajuela Lake and Gatun Lake as they steadily reduce its water storage capacity. The main aim of my diploma thesis is to quantify the sediment yield from the two sub-basins supplying water for the Panama Canal, namely the Alhajuela Lake and the Gatun Lake basins. The study will be based on the analysis of flow rate and sediment concentration data. The data was obtained by the Panama Canal Authority in the years 1998 to 2007 at several gauging stations situated on the main streams that feed the lakes. The samples were taken measured in situ-produced sand-sized sediment samples (0.25 to 0.85 mm) to estimate the rate and distribution of sediment generation in the Panama Canal Basin in the years 1998 to 2007 at several gauging stations situated on the main streams that feed the lakes. Results indicate that the upper Alhajuela Lake sub-basin is generating sediment uniformly. This analysis showed that the sediment yield rates of 195 to 1109 [tons/km2/year] for the Alhajuela Lake with the flow rates of 61.3 to 106 [m3/s] and then to Gatun Lake, the sediment yield rates of 136 to 339 [tons/km2/year] with the flow rates of 57.0 to 109 [m3/s]. The sediment yield measured in the Panama Canal basin, for years 1998 to 2007 are: 5442[tons/km2/year] for Alhajuela Lake and 2349.3 [tons/km2/year] for Gatun Lake. Datasets for land cover, rainfall, slope, flow rate and sediment concentration at several gaunging stations situated on the main streams that feed the lakes; using the final units tons per day [tons/day] (Julien 2010) were used in order to estimate the annual soil loss in each sub-basin. Thus, short-term sediment yields and long-term sediment generations are in balance, which implies steady landscape behavior over time. Such study highlights the importance of proper watershed management in order to reduce the sedimentation of Alhajuela Lake and Gatun Lake in the Panama Canal Basin.

Keywords

Erosion, Sedimentation, Precipitation, Rainfall, Flow rate, Runoff, Lakes

Language used: English

Date on which the thesis was submitted / produced: 14. 4. 2016

Thesis defence

• Supervisor: Ing. Jana Kalibová

Czech University of Life Sciences Prague

Faculty of Environmental Sciences

Master programme / field:
Landscape Engineering / Land and Water Management