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The time of concentration (Tc) is the main hydrological parameter used to characterize the response of a given Hydrological Response Unit (HRU) to a precipitation event. Because of its importance, the determining Tc is an integral step in several studies involving runoff. Thus, this work presents an unprecedented review of the application of Tc in different lines of research involving water resources around the world. In this article, 1252 publications were listed, obtained from seven different databases, published by 2020, that presented the expressions "time of concentration," "runoff," and "watershed." The articles and conference papers obtained in this research were classified into 12 topics. The number of publications per topic and per country was measured and a cluster analysis was developed to verify the similarity of the distribution of topics per country. In addition, 125 equations applied in related publications for the estimation of Tc are also listed.

It is necessary to know the extreme precipitation occurrences in a region for satisfactory design of infrastructure projects. Tropical climate regions are characterized by heavy rainfall events during the summer, and, in recent years, as a result of climate change, such events are becoming recurrent. A theoretical probability distribution model is typically used to extrapolate extreme events for high return periods. This study verified if whether probability distribution models are efficient for estimation of extreme precipitation events for the normative recommended return period. Five cities in Mato Grosso do Sul State, in the Midwest region of Brazil, affected by disasters caused by heavy rainfall were adopted as a case study. The results illustrate that the recommendations of the return periods used for the design of hydraulic control structures are insufficient to avoid damage caused by precipitation events, thus lending a high breakdown risk to structures.

A drenagem urbana sustentável é técnica que visa manter as paisagens naturais e diminuir as áreas impermeáveis, como ocorre quando da implantação do telhado verde. O telhado verde é uma alternativa a ser considerada para os grandes centros urbanos, consistindo na cobertura vegetal de uma edificação, seja sobre laje ou telhado convencional. Neste trabalho foram investigados aspectos e fatores que podem afetar a qualidade do armazenamento do escoamento superficial do telhado verde, bem como sua contribuição ambiental e econômica. Assim, foram analisadas características externas, como clima e estações do ano, e características internas, relacionadas à estrutura física do telhado. Também foram averiguadas as políticas públicas de incentivo à implementação desse tipo de cobertura. O telhado verde contribui para a gestão da drenagem urbana, auxiliando na captação das águas pluviais, podendo melhorar a qualidade do ar e da água e diminuir a sobrecarga do escoamento.

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