A falta de dados hidrológicos é fator limitante da representação mais precisa do comportamento hídrico, comprometendo a gestão de bacias hidrográficas. Quando estas bacias são responsáveis pelo abastecimento publico a situação torna-se crítica. Este trabalho tem como objetivo desenvolver uma metodologia para avaliação da disponibilidade hídrica para o abastecimento, utilizando cenários adaptados ao clima do cerrado, mesmo com carência de dados hidrometeorológicos, sendo aplicada na Sub-bacia do Ribeirão Taquarussu Grande em Palmas-TO. A proposta de metodologia consiste na Estimava da Oferta Hídrica, onde propôs obter os dados de disponibilidade hídrica através dos Métodos de Proporção de Área, de Regressão e do modelo chuva-vazão Win_IPH II, posteriormente adotando a Q90 e a Q7,10 como as vazões de referência; na Estimativa da Demanda e Projeções, que identificou os usos consultivos e a taxa de crescimento da população urbana e rural, da criação animal e os seus respectivos consumos per capita, necessária para a projeção de demanda futura; nos Cenários Propostos, foram aplicadas simulações para atendimento do abastecimento publico no horizonte de 20 anos, considerando a variabilidade climática na região e/ou inserção de novos usuários, no qual a vazão de referência adotada foi cotejada com a curva de demanda, avaliando a disponibilidade hídrica e identificando a variação do máximo déficit. Os resultados obtidos foram que a metodologia proposta se mostrou adequada, como uma ferramenta de analise e tomadas de decisões no gerenciamento integrado dos usos dos recursos hídricos; observou que a Q90 e a Q7,10 anual adotada restringe o uso da água na maior parte do tempo, enquanto a Q90 e a Q7,10 mensal possui uma maior capacidade de disponibilizar água; o maior usuário da Sub-bacia do Ribeirão Taquarussu Grande é a população urbana do município de Palmas, sendo esta responsável por 98,5% do total consumido; nos cenários, o Caso 01 do Cenário 02, demonstrou ser a tendência futura no atendimento da demanda de 66% da população urbana (ETA 006) utilizando a Q90 mensal, tendo o déficit de 47,17% no ano de 2010. / The lack of hydrological data is a limitante factor of the most precise representation of the hydric behaviour, compromising the management of hydrological basins, when these basins are responsible for the publish supply the situation becomes critical.This paper proposes a methodology for assessment of watershed conditions in the supply scenarios adapted to the scarcity of hydrometeorological data, being applied in the sub-basin of the Great Stream Taquarussu Palmas-TO.The proposed methodology is the estimate of Water Supply, which aimed to obtain data on water availability through the methods of Area Ratio, Regression and model rainfall-runoff Win_IPH II, later adopting the Q90 and Q7,10 as the flow of reference; Estimation of the Demand and Projections, which identified the uses advisory and the growth rate of urban and rural population of the animal creation and their respective per capita, which is necessary for the projection of future demand, in the proposed scenario, simulations were applied to attend the public supply in the 20-year horizon, given the climate variability in the region and / or adding new users, in which the reference flow used was checked against the demand curve, assessing water availability and identifying the shift of the maximum deficit and Estimated Cost of Work, which has proposed alternatives to increase water availability by estimating the costs of these works. The results were that the proposed methodology was adequate as a tool for analysis and decision making in integrated management of water resources uses; noted that the Q90 and Q7,10 adopted restricts the annual water use in most of the time , While the Q90 and Q7,10 monthly has a greater capacity to provide water, the biggest user of the Sub-basin Taquarussu Ribeirão Grande is the Palmas city urban population which is responsible for 98.5% of total consumption, in the scenarios, the case 01 of Scenario 02, proved to be the future trend in meeting demand of 66% of urban population (ETA 006) monthly using the Q90, with the deficit of 47.17% in 2010.

This research is part of continued efforts to correlate the hydrology of East Fork Poplar Creek (EFPC) and Bear Creek (BC) with the long term distribution of mercury within the overland, subsurface, and river sub-domains. The main objective of this study was to add a sedimentation module (ECO Lab) capable of simulating the reactive transport mercury exchange mechanisms within sediments and porewater throughout the watershed. The enhanced model was then applied to a Total Maximum Daily Load (TMDL) mercury analysis for EFPC. That application used historical precipitation, groundwater levels, river discharges, and mercury concentrations data that were retrieved from government databases and input to the model. The model was executed to reduce computational time, predict flow discharges, total mercury concentration, flow duration and mercury mass rate curves at key monitoring stations under various hydrological and environmental conditions and scenarios. The computational results provided insight on the relationship between discharges and mercury mass rate curves at various stations throughout EFPC, which is important to best understand and support the management mercury contamination and remediation efforts within EFPC.

A primeira parte deste trabalho consistiu na instalação de pluviógrafos e linígrafos e levantamento de eventos hidrológicos com a obtenção de dados da distribuição espacial de precipitações observadas e hidrogramas resultantes. Experimentos de infiltração de água no solo foram realizados a partir de infiltrômetro de disco a fim de caracterizar a variabilidade espacial da condutividade hidráulica na bacia, obtendo-se dois conjuntos de dados que mostraram ser lognormalmente distribuídos com médias iguais a 15,8 mm/h e 5,47 mm/h. Estudo teórico foi conduzido na segunda parte do trabalho compreendendo o desenvolvimento de modelo hidrológico. A concepção do modelo parte da premissa de que toda a área da bacia possa ser representada por células derivadas de um modelo numérico de terreno (MNT), especificando-se em cada célula o equacionamento hidráulico-hidrológico. As heterogeneidades do solo e da precipitação foram estudadas através de simulação do modelo considerando-se distribuições espaciais diferentes para a condutividade hidráulica saturada e eventos de chuva. Os resultados mostraram que as diferenças entre as vazões de pico podem ser maiores que 100% , considerando-se graus de resolução máximo e mínimo quanto à precipitação, e reafirmaram o consenso de que o conhecimento da distribuição espacial da chuva é fundamental na calibração de modelos hidrológicos distribuídos. / In first part of this work consists on the installation of pluviographic, water-height graphs and surveying of hydrological events with obtained data from spatial distribution of precipitation observed and resultant hydrograms. Experiments of water infiltration in the soil were done by an infiltrometer disc to characterize the spatial variability of hydraulic conductivity and the losses of infiltration in the basin obtaining two sets of data that showed to be lognormally distributed in average equal to 15.8 mm/h and 5.47 mm/h. A theoric study was conduced in the second part of work comprehending the development of hydrologic model distributed. The conception of the model proceed from the premise that allbasin area can be represented by cells derived from a Digital Terrain Model (DTM) specifying in each cell the hydraulic equation - hydrologic. The soil heterogeneity and the precipitation were studied by model simulation considering spatial distributions different to the hydraulic conductivity satured of the soil and to pluvial events. The results pointed out the differences among peak outflow can be more than 100% considering minimum and maximumresolution degrees as the precipitation and affirmed the consensus that the acquaintance of the pluvial spatial distribution is fundamental in the adjustment of hydrologic models distributed.

A primeira parte deste trabalho consistiu na instalação de pluviógrafos e linígrafos e levantamento de eventos hidrológicos com a obtenção de dados da distribuição espacial de precipitações observadas e hidrogramas resultantes. Experimentos de infiltração de água no solo foram realizados a partir de infiltrômetro de disco a fim de caracterizar a variabilidade espacial da condutividade hidráulica na bacia, obtendo-se dois conjuntos de dados que mostraram ser lognormalmente distribuídos com médias iguais a 15,8 mm/h e 5,47 mm/h. Estudo teórico foi conduzido na segunda parte do trabalho compreendendo o desenvolvimento de modelo hidrológico. A concepção do modelo parte da premissa de que toda a área da bacia possa ser representada por células derivadas de um modelo numérico de terreno (MNT), especificando-se em cada célula o equacionamento hidráulico-hidrológico. As heterogeneidades do solo e da precipitação foram estudadas através de simulação do modelo considerando-se distribuições espaciais diferentes para a condutividade hidráulica saturada e eventos de chuva. Os resultados mostraram que as diferenças entre as vazões de pico podem ser maiores que 100% , considerando-se graus de resolução máximo e mínimo quanto à precipitação, e reafirmaram o consenso de que o conhecimento da distribuição espacial da chuva é fundamental na calibração de modelos hidrológicos distribuídos. / In first part of this work consists on the installation of pluviographic, water-height graphs and surveying of hydrological events with obtained data from spatial distribution of precipitation observed and resultant hydrograms. Experiments of water infiltration in the soil were done by an infiltrometer disc to characterize the spatial variability of hydraulic conductivity and the losses of infiltration in the basin obtaining two sets of data that showed to be lognormally distributed in average equal to 15.8 mm/h and 5.47 mm/h. A theoric study was conduced in the second part of work comprehending the development of hydrologic model distributed. The conception of the model proceed from the premise that allbasin area can be represented by cells derived from a Digital Terrain Model (DTM) specifying in each cell the hydraulic equation - hydrologic. The soil heterogeneity and the precipitation were studied by model simulation considering spatial distributions different to the hydraulic conductivity satured of the soil and to pluvial events. The results pointed out the differences among peak outflow can be more than 100% considering minimum and maximumresolution degrees as the precipitation and affirmed the consensus that the acquaintance of the pluvial spatial distribution is fundamental in the adjustment of hydrologic models distributed.

As hydrological computer modeling software continues to increase in complexity, the need for further understanding of the value of different model input datasets becomes apparent. Frequently used precipitation model input include rain gauge data and next-generation radar–based (NEXRAD) rainfall data. Rain gauge data are usually interpolated across a model domain using various methods including the Thiessen Polygon methodology, which may be data-sparse in some areas and overly data-dense in others. However, rain gauge data are generally very easy to use in hydrologic model development, often requiring little to no data processing. NEXRAD data have the potential to improve hydrologic runoff estimates due to the increased spatial resolution of the data: but has its own issues regarding accuracy, false precipitation indications, and difficulties due to data processing. Previous studies have investigated the value of NEXRAD input versus traditional rain gauge data inputs for hydrologic studies; however, results are inconclusive as to which precipitation source provides more accurate results. Limited work has been done to compare the value of these datasets at multiple spatial scales, especially in Florida, a study area dominated by low topographic drive and sub-tropical weather. In addition, little to no research has been done regarding the value of NEXRAD versus rain gauge data inputs at different rainfall return frequencies. The proposed research will utilize a hydrological rain-runoff model (HEC-HMS) of the Upper St. Johns River Basin, Florida to compare the performance of the two precipitation data input types at various watershed spatial scales and rainfall return frequencies. Statistical analysis of the hydrological model “goodness-of-fit” results will be utilized to assess the watershed scaling and rainfall frequency requirements to xii which NEXRAD data provide little to no advantage over standard rain gauges using the Thiessen Polygon method for estimating rainfall totals across a model domain.

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.

Throughout many of the world’s mountain ranges snowpack accumulates during the winter and into the spring, providing a natural reservoir for water. As this reservoir melts, it fills streams and recharges groundwater for over 1 billion people globally. Despite its importance to water resources, our understanding of the storage capacity of mountain snowpack is incomplete. This partial knowledge limits our abilities to assess the impact that projected climate conditions will have on mountain snowpack and water resources. While understanding the effect of projected climate on mountain snowpack is a global question, it can be best understood at the basin scale. It is at this level that decision makers and water resource managers base their decisions and require a clarified understanding of basin's mountain snowpack. The McKenzie River Basin located in the central-western Cascades of Oregon exhibits characteristics typical of many mountain river systems globally and in the Pacific Northwestern United States. Here snowmelt provides critical water supply for hydropower, agriculture, ecosystems, recreation, and municipalities. While there is a surplus of water in winter, the summer months see flows reach a minimum and the same groups have to compete for a limited supply. Throughout the Pacific Northwestern United States, current analyses and those of projected future climate change impacts show rising temperatures, diminished snowpacks, and declining summertime streamflow. The impacts of climate change on water resources presents new challenges and requires fresh approaches to understanding problems that are only beginning to be recognized. Climate change also presents challenges to decision makers who need new kinds of climate and water information, and will need the scientific research community to help provide improved means of knowledge transfer. This dissertation quantified the basin-wide distribution of snowpack across multiple decades in present and in projected climate conditions, describing a 56% decrease in mountain snowpack with regional projected temperature increases. These results were used to develop a probabilistic understanding of snowpack in projected climates. This section described a significant shift in statistical relations of snowpack. One that would be statistically likely to accumulate every 3 out of 4 years would accumulate in 1 out of 20 years. Finally this research identifies methods to improved knowledge transfer from the research community to water resource professionals. Implementation of these recommendations would enable a more effective means of dissemination to stakeholders and policy makers. While this research focused only on the McKenzie River Basin, it has regional applications. Processes affecting snowpack in the McKenzie River Basin are similar to those in many other maritime, forested Pacific Northwest watersheds. The framework of this research could also be applied to regions outside of the Pacific Northwestern United States to gain a similar level of understanding of climate impacts on mountain snowpack. / Graduation date: 2012

Numerous studies indicate that the hydrology of a river basin is influenced by Land Use Land Cover (LULC) and climate. LULC affects the quality and quantity of water resources through its influence on Evapotranspiration (ET) and initiation of surface runoff while climate affects the intensity and spatial distribution of rainfall and temperature which are major drivers of the hydrologic cycle. Literature reports several works on either the effect of changing LULC or climate on the hydrology. However, changes in LULC and climate occur simultaneously in reality. Thus, there is a need to perform an integrated impact assessment of such changes on the hydrological regime at a basin scale. In order to carry out the impact assessment, physically-based hydrologic models are often employed. The present study focuses on assessment of the effect of changing LULC and climate on the hydrology of the Upper Ganga basin (UGB), India, using the Variable Infiltration Capacity (VIC) hydrologic model. In order to obtain the changes that have occurred in the LULC of the basin over a time period, initially LULC analysis is carried out. For this purpose, high resolution multispectral satellite imageries from Landsat are procured for the years 1973, 1980, 2000 and 2011. The images are pre-processed to project them to a common projection system and are then co-registered. The processed images are used for classification into different land cover classes. This step requires training sites which are collected during the field visit as part of this work. The classified images, thus obtained are used to analyse temporal changes in LULC of the region. The results indicate an increase in crop land and urban area of the region by 47% and 122% respectively from 1973 to 2011. After initial decline in dense forest for the first three decades, an increase in the dense forest is observed between 2000- 2011 (from 11.44% to 14.8%). Scrub forest area and barren land are observed to decline in the study region by 62% and 96% respectively since 1973. The land cover information along with meteorological data and soil data are used to drive the VIC model to investigate the impact of LULC changes on streamflow and evapotranspiration (ET) components of hydrology in the UGB. For the simulation purpose, the entire basin is divided into three regions (1) upstream (with Bhimgodha as the outlet), (2) midstream (with Ankinghat as the outlet) and (3) downstream (with Allahabad as the outlet). The VIC model is calibrated and validated for all the three regions independently at monthly scale. Model performance is assessed based on the criterion of normalized root mean square error (NRMSE), coefficient of determination (R2) and Nash-Sutcliffe efficiency (NSE). It is observed that the model performed well with reasonable accuracy for upstream and midstream regions. In case of the downstream region, due to lack of observed discharge data, model performance could not be assessed. Hence, the simulations for the downstream region are performed using the calibrated model of the midstream region. The model outputs from the three regions are aggregated appropriately to generate the total hydrologic response of the UGB. Using the calibrated models for different region of the UGB, sensitivity analysis is performed by generating hydrologic scenarios corresponding to different land use (LU) and climate conditions. In order to investigate the impact of changing LU on hydrological variables, a scenario is generated in which climate is kept constant and LU is varied. Under this scenario, only the land cover related variables are altered in the model keeping the meteorological variables constant. Thus, the effect of LU change is segregated from the effect of climate. The results obtained from these simulations indicated that the change in LU significantly affects peak streamflow depth which is observed to be 77.58% more in August 2011 in comparison with the peak streamflow of August, 1973. Furthermore, ET is found to increase by 46.44% since 1973 across the entire basin. In order to assess the impact of changing climate on hydrological variables, a scenario is generated in which LU is kept constant and climate is varied from 1971-2005. Under this scenario, land cover related variables are kept constant in the model and meteorological variables are varied for different time periods. The results indicate decline in the simulated discharge for the years 1971, 1980, 1990, 2000 and 2005, which is supported by decline in observed annual rainfall for the respective years. Amongst 1971 and 2005, year 2005 received 26% less rainfall resulting in 35% less discharge. Furthermore, ET is observed to be negligibly affected. To understand the integrated impact of changing LU and climate on hydrological variables, a scenario is generated in which both climate and LU are altered. Based on the data available, three years (1973, 1980 and 2000) are considered for the simulations. Under this scenario, both land cover and meteorological variables are varied in the model. The results obtained showed that the discharge hydrograph for the year 1980 has significantly higher peak compared to the hydrographs of years 1973 and 2000. This could be due to the fact that the year 1980 received maximum rainfall amongst the three years considered for simulations. Although the basin received higher rainfall in the year 1980 compared to that in 2000, ET from the basin in the year 1980 is found to be 21% less than that of the year 2000. This could be attributed to the change in LU that occurred between the years 1980 and 2000. Amongst the years 1973 and 2000, there is not much difference in the observed rainfall but ET for the year 2000 is observed to be significantly higher than that of year 1973. It is concluded from the present study that in the UGB, changing LULC contributes significantly to the changes in peak discharge and ET while rainfall pattern considerably influences the runoff pattern of the region. Future work proposed includes assessment of hydrologic response of basin under future LULC and climate scenarios. Also the model efficiency can be assessed by performing hydrologic simulations at different grid sizes.

In this study Bradford’s (2008) approach for setting ecological flow and water level targets is tested and refined through application within the Lake Simcoe Region Conservation Authority’s (LSRCA) subwatershed of Lover’s Creek. A method for defining subwatershed objectives and identifying habitat specialists through expert input is proposed and tested. The natural regime of each streamflow and wetland site is characterized along with the hydrological alteration at each site. Potential ecological responses to the hydrologic alterations are then hypothesized for the different types of changes calculated at each site. Methods for setting overall ecosystem health and specific ecological objective flow targets are proposed and tested. These targets are integrated into a flow regime for each site and a process for using this information for decision making is suggested. Flow magnitude quantification is attempted using hydraulic modelling and sediment transport equations, however the data used were found to be inadequate for this application. The accuracy of the targets developed using the method presented in this paper is mainly limited by the accuracy of the hydrological model and quantified flow magnitudes. Recommendations for improving these components of the assessment are made. The unique approach and recommendations presented in this paper provide explicit steps for developing flow targets for subwatersheds within the LSRCA. This research contributes toward the advancement of EFA within the LSRCA, which provides opportunity for enhanced protection and restoration of ecosystem health across the watershed. / Lake Simcoe Region Conservation Authority