The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on December 21, 2009). Thesis advisor: Dr. Yingkui (Philip) Li. Includes bibliographical references.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Over the years, urban growth occurred in regions close to watersheds, making difficult the recharge areas of these basins and having consequences as urban flooding. Based on the study of urban watersheds, this work aims to estimate and delineate floatable areas around Monjolo Stream in Patos de Minas. Thus, from the application of hydrologic models (Method Santa Barbara) and hydraulic (kinematic wave) in computer flooding simulation, for different urbanization growth scenarios from remaining area of the basin, extreme floods situations were defined, which are the mimínas (approximately 2000 m² of envelopment and faster recovery time area) and maximum (return time of 100 years with the highest envelopment areas). Furthermore, this study verified the effects, on basin macro drainage, different rates of permeable areas in occupied allotments. In these simulations, we observed the appearance of adjacent flooding to the artificial watercourse, proving that for certain precipitation and basin urbanization scenarios, the overflow occurs at some points of its extension. With the base of inundograma significant widening, it was observed that there is an evident trend of longer lasting floods, with basin growing occupation. Analysing the simulation results, it was possible to establish a suggested maximum occupancy rate of 55% for the basin. This study also proposes the adoption of a minimum permeable area rate of at least 37% in future allotment, with 100% urbanization of the remaining area in order to prevent flooding on the Stream Monjolo Basin. This work analysis and observations, can be used by gestors to a more suitable urban planning, regards the basin occupation. / Ao longo dos anos, o crescimento das cidades ocorreu nas regiões próximas às bacias hidrográficas, dificultando as áreas de recarga dessas bacias e tendo como consequências as enchentes urbanas. Baseando-se no estudo de bacias urbanas, este trabalho tem o objetivo de estimar e delimitar áreas inundáveis da bacia do Córrego do Monjolo em Patos de Minas. Desta forma, a partir da aplicação de modelos hidrológicos (Método Santa Bárbara) e hidráulicos (onda cinemática) na simulação computacional de enchentes para diferentes cenários de crescimento da urbanização da área remanecente a montante da bacia, foram definidas situações extremas de enchentes, que são as mimínas (aproximadamente 2000 m² de área de envoltória e menor tempo de retorno) e as máximas (tempo de retorno de 100 anos com as máximas áreas de envoltórias). Além disso, este trabalho verificou os efeitos, na macrodrenagem da bacia, de diferentes taxas de áreas pemeáveis na ocupação dos loteamentos. Nas simulações realizadas, constatou-se o surgimento das inundações adjacentes ao canal artificial, comprovando que, para determinados cenários de precipitação e de urbanização da bacia, ocorre o transbordamento em alguns pontos da sua extensão. Com alargamento significativo da base do inundograma foi observado que fica evidente a tendência das enchentes perdurarem por mais tempo, com a crescente ocupação da bacia. Com a análise dos resultados das simulações, foi possível estabelecer uma taxa de ocupação máxima sugerida de 55%, para a bacia. Este estudo também propôs a adoção de uma área permeável mínima de 37% nos futuros lotes, com uma urbanização de 100% da área remanescente, de forma a evitar as inundações na Bacia do Córrego do Monjolo. Por meio destas análises e observações, este trabalho pode ser utilizado pelos gestores para um planejamento urbano mais adequado, no que diz respeito à ocupação da bacia. / Mestre em Engenharia Civil

Les bassins versants du pourtour méditerranéen français sont touchés par des pluies parfois intenses et à fort cumuls, qui peuvent engendrer des crues à cinétique rapide. Les derniers exemples majeurs en date sont ceux de l’Aude en 1999, du Gard en 2002 et du Var en 2010, dont les conséquences furent dramatiques. Ces travaux de thèse visent à évaluer une approche de modélisation complémentaire aux outils dont disposent déjà les Services de Prévision des Crues pour la prévision des crues à cinétique rapide : le couplage de modèles hydrologique et hydraulique, qui est a priori adapté pour la modélisation à l’échelle des grands bassins méditerranéens, de superficies supérieures à 1 000 km² (Ardèche, Cèze, Gardon, Vidourle…). Des éléments de réponses aux 4 questions suivantes sont recherchés : 1) le couplage est-il adapté pour la modélisation des débits atteints lors d’évènements passés, d’importance intermédiaire ? 2) le couplage est-il performant pour la modélisation des débits, cotes atteintes, et extension d’inondation, observés lors d’un épisode majeur? 3) comment envisager d’améliorer la modélisation des apports latéraux non-jaugés au modèle hydraulique, tout en adoptant une démarche adaptée à la prévision ? 4) le couplage est-il performant en prévision ? Le couplage employé combine le modèle hydrologique SCS-LR de la plateforme ATHYS (Bouvier et al., 2004), et le code de modélisation hydraulique 1D MASCARET (EDF-CETMEF, 2011). Il est appliqué au bassin versant du Gardon (2 040 km²), dans le sud de la France. / The French catchments around the Mediterranean Sea are affected by intense rains, which can cause fast and flash floods. The last major events are the one of the Aude river in 1999, of the Gard area in 2002, and of the Var area in 2010, whose consequences were tragic. This PhD intends to assess a modeling strategy complementary to the tools that are already used by the regional flood warning services: the coupling of hydrologic and hydraulic models, which is a priori well-adapted for the modelling of catchments of large-scale areas (larger than 1 000 km²) around the Mediterranean Sea (such as the ones of the Ardèche river, the Cèze river, the Vidourle river, the Gardon river…). The works aim at bringing elements of responses to the following questions: 1) is the coupling adapted to the modelling of floods hydrographs of past events of moderate importance? 2) in case of an extreme event (like in September 2002), is the coupling effective for the modelling of discharges, of water levels, and of flood extension? 3) how can we improve the modelling of ungauged lateral inflows to the hydraulic model, while applying a method adapted to forecasting? 4) Is the coupling efficient at forecasting? The coupling used combines the SCS-LR hydrologic model of the ATHYS platform (Bouvier et al., 2004), and the MASCARET 1D hydraulic model (EDF-CETMEF, 2011). It is applied to the Gardon river basin (2 040 km²), in the South of France.