Abstract

This paper compares three methods to obtain synthetic unit hydrographs (SUH). The Snyder (modified for Chile by Astorga and Benitez), the US Bureau of Reclamation, and the Temez methods are analyzed on two watersheds located in Mediterranean areas of Chile. To do so, each watershed was characterized in terms of its morphology and vegetation type. In addition, data from three actual storms, with high, medium, and low rainfall intensities, were used to obtain direct runoff hydrographs (DRH) for both watersheds. The NRCS Curve Number method was used to estimate runoff responses to storm events. Our results suggest that, in general, the SUH used had no significant differences between watersheds. On the other hand, the Snyder SUH method was the only one that found significant differences in the DRHs relative to the other methods and only under a high-intensity storm in the Cunculen watershed.