Sediment Transport in the Jequetepeque River and its Impact on the Gallito Ciego Dam, Peru.

Eusebio Ingol Blanco, Oswaldo Ortiz Vera, Abel Mejia Marcacuzco

Thursday 2 july 2015

9:00 - 9:15h at Mississippi (level 1)

Themes: (T) Sediment management and morphodynamics, (ST) Sediment transport mechanisms and modelling

Parallel session: 10A. Sediment - Transport

Sediment Transport in the Jequetepeque River and its Impact on the Gallito Ciego Dam, Peru. Oswaldo Ortiz-Vera1, Abel Mejia-Marcacuzco1 and Eusebio Ingol-Blanco2 1Water Resources Engineering Program, Universidad Nacional Agraria La Molina, Lima, Peru; PH (511) 340 -1180; email:, 2 Autoridad Nacional del Agua, Universidad Nacional Agraria La Molina and Universidad San Ignacio de Loyola, Lima, Peru; PH (511) 348-1971; email: Abstract This research focuses on evaluate the annual rate of sediment transport of the Jetepeque River, located in the northern of Peru, and its effect on the Gallito Ciego Dam. This dam, which started its operation in April 1988, is one of the most important of the regulated basins in Peru and the last ten years has reduced its capacity by more than 20 % due to the sediment discharge into the reservoir from the upper basin. For this study, a record of peak flows (1920-21, 1987-88) of Ventanillas hydrometric station (07 º 17'S, 79 ° 17'W), the technical characteristics of the dam and the overall results of bathymetry (April, 1999) were used. Gumbel probabilistic model and the empirical equation of Meyer-Peter were used to predict the flows and annual sedimentation in the reservoir, respectively. The results are consistent with the predicted rate by this study (9 x 106 m3 per year) and those obtained from bathymetric studies (8.82 x 106 m3 per year); however, both are highly divergent with the design rate of the project (1.7 x 106 m3 per year), which evidences a weakness of the original sedimentological study, in addition, by the lack of water management programs and sediment control causing the early failure of the dam. Furthermore, the active storage of the reservoir has been reduced considerably. Key words: Sediment transport, Jequetepeque river, Gallito Ciego Dam.