Resumen

CAMPOS-ARANDA, Daniel F.. Empirical approach to the bivariate solution for flood desing in reservoirs without hydrometrical data. Agrociencia [online]. 2010, vol.44, n.7, pp.735-752. ISSN 2521-9766.

The estimation of design floods, putting together hydrometric information of annual maximum flows and their corresponding volumes in their hydrographs (V), has been resolved in México through the bivariate probabilistic analysis. The solutions of this procedure applied to 15 existing dams and one in draft were analyzed looking for a pattern of statistical behavior and formulating an empirical approach that does not require the above information. According to this approach, the hydrograph of the design flood has a peak flow (Qp) with a return period of 275 years, an estimation based on regional methods. Its peak time (Tp) is equal to the time of concentration of the basin and its shape and volume (V) are defined by a synthetic Gamma type hydrograph with 3.975 as shape parameter. The contrast between the elements (Qp, Tp and V) of the empirical approach and the bivariate solution leads to maximum relative errors by default in Qp not over 21 %, which do not transfer to the relative error of V. Two numerical applications were performed; the first in a small watershed dam with no hydrometric data, and the second in a reservoir under construction with a large gauged basin. The procedure developed is shown to be quite simple and accurate, of the utmost importance when checking the hydrological safety of thousands of dams that have no hydrometric information, and because of their characteristics of location, capacity and design age are dangerous hydraulic structures.

Palabras llave : hydrological safety; design hydrographs; time of concentration; Gamma hydrographs; Las Animas dam; El Zapotillo project.