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A presente pesquisa dissertativa foi desenvolvida para investigar como professores de Geografia de escolas da rede pública estadual de Ibitinga-SP têm trabalhado o tema hidrografia em suas práticas pedagógicas. Procuramos descrever criticamente como se dão as práticas escolares de professores de Geografia em relação à hidrografia local, refletir sobre a importância de se desenvolver práticas que tratem da localidade na qual os alunos estão inseridos e analisar as práticas dos professores, tendo em vista o desenvolvimento de uma consciência socioambiental e cidadã dos alunos. A abordagem metodológica escolhida foi a qualitativa, o que possibilitou uma avaliação dos processos e das características intrínsecas do ensino. Os procedimentos para a coleta de dados envolveram entrevistas semi-estruturadas com três professores participantes, observações das aulas em que foram desenvolvidos os temas hidrografia e localidade, e análise dos documentos produzidos e utilizados pelos professores e alunos no desenvolvimento do tema em questão. Realizamos a caracterização das escolas e dos professores participantes da pesquisa. Os dados coletados e as análises realizadas evidenciaram que as práticas escolares estão atreladas ao currículo oficial implementado pelo programa São Paulo Faz Escola, que limita o estabelecimento de relações com a localidade, abordando a Hidrografia Geral e não a da localidade. As práticas escolares decorrem de pressões sofridas pelos professores para cumprirem o currículo prescrito pela Secretaria de Educação, à carga horária muito extensa e à dificuldade que eles têm em encontrar informações sistematizadas sobre o tema para a localidade em estudo. / This research was carried out to investigate how Geography teachers from public schools of Ibitinga, São Paulo, have been teaching Hydrographs with their students. We have been looking for describing how the school practices of selected teachers have been worked in relation to Local Hydrographs, thinking about relationship between locality and the students life and discussing the teachers practices with eyes on construction of social and environmental conscience for students. The applied methodology for data collection included an interview, teachers lessons and document review. The methodological approach was qualitative to avoid better evaluations of processes and intrinsic characteristics of the teaching. A description of participating schools and teachers was performed. Data analysis demonstrated that school practices have been overruled by official program named São Paulo Faz Escola what restrains the Locality teaching. School practices have been originated from hard pressure in teachers carrying out the official lessons prescribed from government, their heavy workload and due to their difficulties to find organized information of Locality.

A presente pesquisa dissertativa foi desenvolvida para investigar como professores de Geografia de escolas da rede pública estadual de Ibitinga-SP têm trabalhado o tema hidrografia em suas práticas pedagógicas. Procuramos descrever criticamente como se dão as práticas escolares de professores de Geografia em relação à hidrografia local, refletir sobre a importância de se desenvolver práticas que tratem da localidade na qual os alunos estão inseridos e analisar as práticas dos professores, tendo em vista o desenvolvimento de uma consciência socioambiental e cidadã dos alunos. A abordagem metodológica escolhida foi a qualitativa, o que possibilitou uma avaliação dos processos e das características intrínsecas do ensino. Os procedimentos para a coleta de dados envolveram entrevistas semi-estruturadas com três professores participantes, observações das aulas em que foram desenvolvidos os temas hidrografia e localidade, e análise dos documentos produzidos e utilizados pelos professores e alunos no desenvolvimento do tema em questão. Realizamos a caracterização das escolas e dos professores participantes da pesquisa. Os dados coletados e as análises realizadas evidenciaram que as práticas escolares estão atreladas ao currículo oficial implementado pelo programa São Paulo Faz Escola, que limita o estabelecimento de relações com a localidade, abordando a Hidrografia Geral e não a da localidade. As práticas escolares decorrem de pressões sofridas pelos professores para cumprirem o currículo prescrito pela Secretaria de Educação, à carga horária muito extensa e à dificuldade que eles têm em encontrar informações sistematizadas sobre o tema para a localidade em estudo. / This research was carried out to investigate how Geography teachers from public schools of Ibitinga, São Paulo, have been teaching Hydrographs with their students. We have been looking for describing how the school practices of selected teachers have been worked in relation to Local Hydrographs, thinking about relationship between locality and the students life and discussing the teachers practices with eyes on construction of social and environmental conscience for students. The applied methodology for data collection included an interview, teachers lessons and document review. The methodological approach was qualitative to avoid better evaluations of processes and intrinsic characteristics of the teaching. A description of participating schools and teachers was performed. Data analysis demonstrated that school practices have been overruled by official program named São Paulo Faz Escola what restrains the Locality teaching. School practices have been originated from hard pressure in teachers carrying out the official lessons prescribed from government, their heavy workload and due to their difficulties to find organized information of Locality.

The study was aimed at developing a simple methodology for flow prediction in ungauged basins using existing data resources. For this purpose, the streamflow measurements across the Kentucky River Basin located in Kentucky, USA were obtained from United States Geological Survey (USGS) archive. The flow transferring characteristics of the subbasins of the Kentucky River Basin were obtained by combining downstream and upstream stream gauges. The flow transferring function thus derived were related to watershed, channel and flow characteristics of the subbasins by multiple regression analysis. The gauge pairs were divided into two classes of subbasins representing Upper and Lower Kentucky, which were characterized mainly by the geology of the watersheds. The regression models corresponding to the two groups of subbasins were applied to example gauge pairs to evaluate the efficiency of the proposed model to predict streamflow in downstream channel. The estimated hydrographs agreed with the observed hydrographs with the performance efficiency of greater than 90%. The proposed method was tested for its applicability in first-order streams in the Goose Creek, a tributary to the Kentucky River. The overland flow component for the first-order streams was determined using TOPMODEL with topography, soil and climatic factors as inputs. The overland flow was routed to the Goose Creek outlet using the transfer function obtained from measured flow records. The simulated hydrographs were reproduced with 80% accuracy when compared with the observed hydrographs. The flow prediction of first-order ungauged streams was automated by the back-calibration algorithm. The algorithm is supported by the Shuffled Complex Evolution - University of Arizona algorithm for its optimization routine. The back-calibration procedure optimizes each first-order stream with the aid of the flow transferring function. The back-calibration procedure was imbedded in a Visual Basic.NET environment to automatically predict flow on a daily time scale and predicted was published on the internet using ESRI Arc Internet Mapping Server (ArcIMS). The project thus provides daily streamflow estimation for streams on a first-order level on every day basis, which will facilitate flow prediction of streams regardless of the size of the watersheds.

Florida's Department of Transportation requires design storm tide hydrographs for coastal waters surrounding tidal inlets along the coast of Florida. These hydrographs are used as open ocean boundary conditions for local bridge scour models. At present, very little information is available on the effect that tidal inlets have on these open coast storm tide hydrographs. Furthermore, current modeling practice enforces a single design hydrograph along the open coast boundary for bridge scour models. This thesis expands on these concepts and provides a more fundamental understanding on both of these modeling areas. A numerical parameter study is undertaken to elucidate the influence of tidal inlets on open coast storm tide hydrographs. Four different inlet-bay configurations are developed based on a statistical analysis of existing tidal inlets along the Florida coast. The length and depth of the inlet are held constant in each configuration, but the widths are modified to include the following four inlet profiles: 1) average Florida inlet width; 2) 100 meter inlet width; 3) 500 meter inlet width; and 4) 1000 meter inlet width. In addition, two unique continental shelf profiles are used to design the ocean bathymetry in the model domains: a bathymetry profile consistent with the west/northeast coast of Florida (wide continental shelf width), and a bathymetry profile similar to the southeast coast of Florida (narrow continental shelf width). The four inlet-bay configurations are paired with each of the bathymetry profiles to arrive at eight model domains employed in this study. Results from these domains are compared to control cases that do not include any inlet-bay system in the computational domain. The ADCIRC-2DDI numerical code is used to obtain water surface elevations for all studies performed herein. The code is driven by astronomic tides at the open ocean boundary, and wind velocities and atmospheric pressure profiles over the surface of the computational domains. Model results clearly indicate that the four inlet-bay configurations do not have a significant impact on the open coast storm tide hydrographs. Furthermore, a spatial variance amongst the storm tide hydrographs is recognized for open coast boundary locations extending seaward from the mouth of the inlet. The results and conclusions presented herein have implications toward future bridge scour modeling efforts. In addition, a hindcast study of Hurricane Ivan in the vicinity of Escambia Bay along the Panhandle of Florida is performed to assess the findings of the numerical parameter study in a real-life scenario. Initially, emphasis is placed on domain scale by comparing model results with historical data for three computational domains: an ocean-based domain, a shelf-based domain, and an inlet-based domain. Results indicate that the ocean-based domain favorably simulates storm surge levels within the bay compared to the other model domains. Furthermore, the main conclusions from the numerical parameter study are verified in the hindcast study: 1) the Pensacola Pass-Escambia Bay system has a minimal effect on the open coast storm tide hydrographs; and 2) the open coast storm tide hydrographs exhibit spatial dependence along typical open coast boundary locations.

<p> Through the use of unit hydrographs this paper demonstrates the effect of land uses on the stream discharge of three watersheds located in Southern Ontario. The watersheds represent urban, agricultural and wetland environments. The three different environments each demonstrate different responses to a unit magnitude of uniformly distributed precipitation. </p> <p> The rainfall events occurred during September and October 1981 and 1986. Three durations of events, six, twelve and twenty-four hours, are studied. </p> <p> The paper demonstrates that an urban watershed experiences a greater magnitude of peak discharge and faster response time than either of the other two studied watersheds. The unit hydrograph resulting from a wetland showed that the wetland watershed was an important regulator of streamflow. </p> <p> Special emphasis were placed on the urbanization of agricultural lands as this is the most applicable land use change currently occurring in Southern Ontario.The results from this study will be useful when assessing the magnitude of the potential runoff problem when these agricultural watersheds are urbanized. </p> / Thesis / Bachelor of Arts (BA)

A key piece of information necessary for water management is accurate streamflow information. However, the available data and resources for gathering information vary around the world. This study forms a part of a research effort to improve discharge estimations for a montane rainforest stream located in the San Lorencito headwater catchment in Costa Rica. The aim of this study is to improve the current rating curve where the high flow part is currently ungauged and look at the impact of adding a high flow estimation to the rating curve. When adding information that is not gauged data, it is important to make sure that the information is unbiased. It can also be questioned if information based on less accurate observations will aid a model. The high flow estimation in this study was calculated using the Manning’s equation based on a survey after a flood event in August 2015. Field measurements were performed at the location in February 2017 and were added to the already existing data record from the gauging station dating back to 2015. Based on the previous data together with the new measurements, rating curves and corresponding hydrographs were established. The impact of adding the Manning’s estimation included a statistical assessment and comparison of the different rating curves and hydrographs. Results showed that at higher flows, the rating curve without the Manning’s point estimated higher discharge than the rating curve determined including the Manning’s point. However, at low flows below 0.9 𝑚3/𝑠 (or around a stage of 0.4 𝑚), the rating curve without the Manning’s point is estimating less discharge than the rating curve including the Manning’s point. Error plots and the uncertainty intervals in the graphs illustrate that the uncertainty at high flows are reduces when including a high flow estimation. The results suggest that it is preferable to add information, even if it has a lot of uncertainty, to no information at all. / Pålitlig flödestatistik och god kunskap gällande vattenföringen i vattendrag är mycket viktiga förutsättningarna för att kunna förvalta vattenresurser på ett hållbart sätt. Tyvärr har inte alla länder samma möjligheter och resurser att samla in den nödvändiga informationen vilket leder till att tillgänglig data är begränsad i vissa delar av världen. Denna studie utgör en del av ett forskningsprojekt i Costa Rica vars syfte är att förbättra uppskattningen av vattenföringen för ett vattendrag som rinner genom ett regnskogsområde. Målet med denna studie är att förbättra den nuvarande avbördningskurvan och undersöka effekten av att lägga till uppskattade värden för höga flöden där det för tillfället saknas data. Under februari 2017 genomfördes flödesmätningar på plats i Costa Rica. Mätningarna användes tillsammans med tidigare uppmätt flödesdata för att bestämma avbördningskurva och motsvarande hydrograf. För att uppskatta det höga flödet användes Mannings ekvation. Beräkningar har utgått från en störtflod som skedde i augusti 2015 och parametrar till ekvationen har baserats på de spår vattnet orsakad på terrängen och vegetation som kunde observeras i efterhand. Slutligen har en statistik bedömning genomförts där effekten på avbördningskurvan och hydrografen av att inkludera en vattenföringspunkt beräknad med Mannings ekvation har studerats. Följden av att ta med en Manningspunkt innebar att avbördningskurvan planades ut och inte uppskattade lika drastiska vattenföringar vid höga vattennivåer. Vid låga flöden under 0.9 𝑚3/𝑠 uppskattade däremot avbördningskurvan med Manningspunkten lägre vattenföring än kurvan utan Manningspunkten. Genom att introducera ett uppskattat vattenföringsvärde med Mannings ekvation minskade osäkerheten för avbördningskurvan och hydrografen vid höga flöden. Resultaten antyder att det är fördelaktigt att införa uppskattade värden där det saknas information.

From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / High nitrates in drinking water are significant in relation to an infant disease, methemoglobinemia, and the U.S. public health service has set a limit of 45 ppm for human consumption. This paper illustrates how chemical hydrographs were used in a study of nitrates in the groundwater of the Fresno-Clovis metropolitan area (F.C.M.A.) of semiarid central California. The area comprises about 145 square miles, with a population of 310,000. Urban water use is entirely derived from wells, whereas the surrounding agriculture relies on surface and ground water. In 1965, the California department of water resources noted nitrate concentrations in the F.C.M.A. were exceeding the safe limit. A number of sources of error in chemical analyses of water quality are noted. A measure of the accuracies of analyses and a method of double-checking anomalous results is furnished by plotting chemical hydrographs of individual wells. Seasonal changes in nitrate were consistent for many parts of the area, and were related to hydrogeologic factors and parameters directly affecting nitrification. Nitrate hydrographs were monitored by chloride hydrographs. The highest nitrate concentrations were in the shallower parts of the aquifer, and well deepening and changes in water level, pumping patterns and recharge rates complicated interpretations. However, the hydrographs helped to pinpoint the source of nitrate in areas where several possible sources were present.

From the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona / A critique of statistical properties of monthly flows on an ephemeral stream in Arizona is given. A subjective procedure, justified for managerial purposes not concerned with the variability of flow within the month, is proposed for sequential generation of monthly flow data. Ephemeral flows should be modeled by starting with at least historical daily flows for more meaningful monthly flow models. Stochastic properties of monthly streamflows and state transition probabilities are reviewed with regard to ephemeral streams. A flow chart for a streamflow model geared to digital computers, with a simulation of streamflow subroutine, is developed. Meaningful monthly flow models could serve as a check on alternative models (subjective matrix, lag-one auto regressive, harmonic, bivariate normal, bivariate log-normal models). Rules and guidelines are presented in developing meaningful probability matrices.

L'estimation de crues de projet est requise pour le dimensionnement de barrages et de bassins de rétention, de même que pour la gestion des inondations lors de l’élaboration de cartes d’aléas ou lors de la modélisation et délimitation de plaines d’inondation. Généralement, les crues de projet sont définies par leur débit de pointe à partir d’une analyse fréquentielle univariée. Cependant, lorsque le dimensionnement d’ouvrages hydrauliques ou la gestion de crues nécessitent un stockage du volume ruisselé, il est également nécessaire de connaître les caractéristiques volume, durée et forme de l’hydrogramme de crue en plus de son débit maximum. Une analyse fréquentielle bivariée permet une estimation conjointe du débit de pointe et du volume de l’hydrogramme en tenant compte de leur corrélation. Bien qu’une telle approche permette la détermination du couple débit/volume de crue, il manque l’information relative à la forme de l’hydrogramme de crue. Une approche attrayante pour caractériser la forme de la crue de projet est de définir un hydrogramme représentatif normalisé par une densité de probabilité. La combinaison d’une densité de probabilité et des quantiles bivariés débit/volume permet la construction d’un hydrogramme synthétique de crue pour une période de retour donnée, qui modélise le pic d’une crue ainsi que sa forme. De tels hydrogrammes synthétiques sont potentiellement utiles et simples d’utilisation pour la détermination de crues de projet. Cependant, ils possèdent actuellement plusieurs limitations. Premièrement, ils reposent sur la définition d’une période de retour bivariée qui n’est pas univoque. Deuxièmement, ils décrivent en général le comportement spécifique d’un bassin versant en ne tenant pas compte de la variabilité des processus représentée par différents types de crues. Troisièmement, les hydrogrammes synthétiques ne sont pas disponibles pour les bassins versant non jaugés et une estimation de leurs incertitudes n’est pas calculée.Pour remédier à ces manquements, cette thèse propose des avenues pour la construction d’hydrogrammes synthétiques de projet pour les bassins versants jaugés et non jaugés, de même que pour la prise en compte de la diversité des types de crue. Des méthodes sont également développées pour la construction d’hydrogrammes synthétiques de crue spécifiques au bassin et aux événements ainsi que pour la régionalisation des hydrogrammes. Une estimation des diverses sources d’incertitude est également proposée. Ces travaux de recherche montrent que les hydrogrammes synthétiques de projet constituent une approche qui s’adapte bien à la représentation de différents types de crue ou d’événements dans un contexte de détermination de crues de projet. Une comparaison de différentes méthodes de régionalisation montre que les hydrogrammes synthétiques de projet spécifiques au bassin peuvent être régionalisés à des bassins non jaugés à l’aide de méthodes de régression linéaires et non linéaires. Il est également montré que les hydrogrammes de projet spécifiques aux événements peuvent être régionalisés à l’aide d’une approche d’indice de crue bivariée. Dans ce contexte, une représentation fonctionnelle de la forme des hydrogrammes constitue un moyen judicieux pour la délimitation de régions ayant un comportement hydrologique de crue similaire en terme de réactivité. Une analyse de l’incertitude a montré que la longueur de la série de mesures et le choix de la stratégie d’échantillonnage constituent les principales sources d’incertitude dans la construction d’hydrogrammes synthétiques de projet. Cette thèse démontre qu’une approche de crues de projet basée sur un ensemble de crues permet la prise en compte des différents types de crue et de divers processus. Ces travaux permettent de passer de l’analyse fréquentielle statistique de crues vers l’analyse fréquentielle hydrologique de crues permettant de prendre en compte les processus et conduisant à une prise de décision plus éclairée. / Design flood estimates are needed in hydraulic design for the construction of dams and retention basins and in flood management for drawing hazard maps or modeling inundation areas. Traditionally, such design floods have been expressed in terms of peak discharge estimated in a univariate flood frequency analysis. However, design or flood management tasks involving storage, in addition to peak discharge, also require information on hydrograph volume, duration, and shape . A bivariate flood frequency analysis allows the joint estimation of peak discharge and hydrograph volume and the consideration of their dependence. While such bivariate design quantiles describe the magnitude of a design flood, they lack information on its shape. An attractive way of modeling the whole shape of a design flood is to express a representative normalized hydrograph shape as a probability density function. The combination of such a probability density function with bivariate design quantiles allows the construction of a synthetic design hydrograph for a certain return period which describes the magnitude of a flood along with its shape. Such synthetic design hydrographs have the potential to be a useful and simple tool in design flood estimation. However, they currently have some limitations. First, they rely on the definition of a bivariate return period which is not uniquely defined. Second, they usually describe the specific behavior of a catchment and do not express process variability represented by different flood types. Third, they are neither available for ungauged catchments nor are they usually provided together with an uncertainty estimate.This thesis therefore explores possibilities for the construction of synthetic design hydrographs in gauged and ungauged catchments and ways of representing process variability in design flood construction. It proposes tools for both catchment- and flood-type specific design hydrograph construction and regionalization and for the assessment of their uncertainty.The thesis shows that synthetic design hydrographs are a flexible tool allowing for the consideration of different flood or event types in design flood estimation. A comparison of different regionalization methods, including spatial, similarity, and proximity based approaches, showed that catchment-specific design hydrographs can be best regionalized to ungauged catchments using linear and nonlinear regression methods. It was further shown that event-type specific design hydrograph sets can be regionalized using a bivariate index flood approach. In such a setting, a functional representation of hydrograph shapes was found to be a useful tool for the delineation of regions with similar flood reactivities.An uncertainty assessment showed that the record length and the choice of the sampling strategy are major uncertainty sources in the construction of synthetic design hydrographs and that this uncertainty propagates through the regionalization process.This thesis highlights that an ensemble-based design flood approach allows for the consideration of different flood types and runoff processes. This is a step from flood frequency statistics to flood frequency hydrology which allows better-informed decision making.