ESTIMATION ON TIME OF CONCENTRATION OF OVERLAND FLOW IN WATERSHEDS: A REVIEW

Abstract

The time of concentration is a fundamental parameter in many hydrological models. Nowadays there is no universally accepted definition for such parameter. However, many definitions and estimation procedures can be found in the technical literature. After an extensive bibliographic review, the current study brings up the variability of empiric methodologies used in its estimations. Thirty empiric methodologies were listed and estimations of time of concentration were performed by applying such methodologies using data from a rural watershed. The hierarchical cluster analysis (Cluster) was applied in order to assess the similarity degree among the selected methodologies. Among all methodologies, Pasini’s and Ventura’s are the ones that present higher similarity to each other, whereas Pasini and Arizona DOT show stronger dissimilarities to each other.