A presente pesquisa concentra-se no estudo hidrológico utilizando o potencial das geotecnologias na modelagem do escoamento na bacia do rio Bengalas, cujo rio principal de mesmo nome, corta o município de Nova Friburgo, RJ, no sentido Sul-Norte. Esse município, um dos mais importantes da região serrana, sofre frequentemente com inundações e deslizamentos, onde, dados históricos e acontecimentos recentes mostram que a ocupação inadequada de encostas e calhas dos rios são as áreas destacada e negativamente afetadas. A metodologia tem suporte no uso de um SIG, extraindo informações, que por sua vez, serão entrada de dados na fase de modelagem, e reforçando a apresentação dos resultados das simulações através de mapas. Ela está divida basicamente em três etapas: "SIG", "Modelagem" e "Suporte à Tomada de Decisão/Simulação". Esse primeiro estudo permitiu compor um banco de dados geográfico com as características fisiográficas da bacia; a seleção criteriosa de uma modelagem matemática e encadeamento de seus parâmetros com os componentes do ciclo hidrológico; realizar a calibração do modelo de transformação chuva-vazão, Soil Conservation Service (CN); e simular a passagem dos volumes gerados pela precipitação efetiva na calha do rio Bengalas, com o objetivo de identificar e analisar as áreas suscetíveis a inundações na porção central da cidade de Nova Friburgo. Modelagem dessa natureza vem sendo empregada, principalmente, no gerenciamento de recursos hídricos, onde a tomada de decisões embasada nos resultados de simulações computacionais, contribuem para evitar prejuízos materiais e financeiros, e ainda, perdas de vidas humanas em áreas de risco, neste caso, aquelas suscetíveis a inundações. Analisando os resultados encontrados temos que a área suscetível à inundação para uma chuva com tempo de recorrência de 50 anos, o mais crítico estudado, seja de aproximadamente 1,0 km, distribuídos nos seus 8,5km na região central de Nova Friburgo-RJ, sendo está, ora delimitada, prioritariamente edificada. / This research focuses on the hydrological study using the potential of geotechnology into runoff modeling of the Bengalas Basin, whose main river, with same name, crosses the city of Nova Friburgo - RJ, in a south-north orientation. This city, one of the most important in "Região Serrana", suffers often with floods and landslides, which, historical data and recent events show that the inappropriate occupation of hillsides and margins of rivers are the highlighted and negatively affected areas. The methodology has basis in a GIS application, extracting information, which in turn, are input in the modeling phase, and enhancing the presentation of simulation results through maps. It is basically divided into three stages: "SIG", "Modelagem" and "Suporte à Tomada de Decisão/Simulação." This first study allowed to compose a geographic database with the physiographic features of the basin; the careful selection of a chain of mathematical modeling and its parameters with the hydrological cycle components, perform the calibration of the rainfall-runoff transformation model, Soil Conservation Service (CN) and simulate the transition of volumes generated by an effective precipitation in the Bengalas river, in order to identify and analyze the susceptible flooding areas in the central part of Nova Friburgo. A kind of this modeling has been used, mainly, in the water resource management, in which decision-making are based on results of computer simulations, helps to avoid a range of losses, such as material, financial and, especially, humans, that in this case, people who lives in areas susceptible to flooding. Analyzing the results, it was found that an area susceptible to flooding by a rainfall with a recurrence time of 50 years, the most critical studied, results in approximately 1.0 km, distributed in its 8.5km (central part of Nova Friburgo - RJ) which this bounded area has a great part with buildings.

This work engages in the watercourse called Mastník. It focuses on the determination of flooded areas for couple of series (Q5, Q10, Q50, Q100) and hydro-technical assessment of particular objects. The chosen section is situated on cadastral area of town Sedlčany in the Central Bohemia region. Its length is 1.973 kms and there is located 5 water management objects reaching to the flow profile of the watercourse. The data for this dissertation has been gained by the Czech State Administration of Land Surveying and Cadaster. It is about the digital relief of the 5th generation of aerial laser scanning. The laser rays are not capable of penetration the water surface, and thus describe the shape of the water-sources bed. So the tool called CroSolver was used to dig the water-sources bed. Then the hydrodynamic model has been created in program called HEC-RAS. From the results of hydrodynamic model then was evaluated the real water-technical state of the object. The outgoing data (dots defining the flood range to the surroundings) was after then inserted to the program ArcMap. Here the flood lines and from them the flood zones were created based on the particular series of the flows.

This thesis deals with determining the flood lines and hydrotechnical assessment of the Říčanský water flow and objects that interfere with the flow profile. Hydrotechnical assessment preceding hydrological study of catchment. The basis for this work was digital model relief Czech Republic, which obtained from Airborne Laser Scanning. This method is considered to be of the most accurate methods for altimetry data obtained, but the near-infrared laser beam used in this method cannot penetrate water masses. The result of this problem is error as the extracted cross sections lose a significant portion of their flow area. These errors can be removed to recess the channel using specialized software Crosolver tool. For hydrotechnical assessment is used hydrodynamic model in HEC-RAS. On the basis of results are determined the flood line for N-years flows (5-years flow, 20-years flow and 100-years flow). The final part of this work deals evaluation of hydrotechnical assessment Říčanský water flow, object and floodplains.

Nowadays, the issue of floods and flood protection is very reflected theme which is dedicated to the thesis. The first part deals with the gathering and the processing of relevant information, the emphasis is on the development of basic questions about flooding and flood protection because of importance for understanding its. The next part of thesis provides a description of the catchment Želivka which involves the interest area which is bounded swells water reservoir Švihov at 41.6182 Km and dykes of water reservoirs Sedlice at 63.8893 Km. The next, the thesis also discusses the modeling of steady flow of flood flows and modeling flood lines in the area of interest. For the simulation are used ArcGIS 10.2 with overlaid of GeoRAS, HEC-RAS 4.1.0 and the description of creating a model for the assembly are used the digital elevation model fifth-generation, transverse profiles of stream, longitudinal profile of stream and roughness of stream and inundation and geometry of objects on the stream. The outcome of this work are maps of inundation in selected sections on the stream, in particular in areas with existing buildings.

By combining FEMA's HAZUS-MH (Hazards U.S. Multi-Hazard) flood-loss estimation software and the HEC-RAS hydraulic modeling package, this study was able to quantify potential beneficial and adverse impacts of flood-control and navigational structures along the Middle Mississippi River (MMR; between Mississippi-Missouri River confluence and Thebes, IL). The goal of this investigation was to assess changes in water-surface elevations and associated flood losses to: 1) quantify the potential exposure of flooding under different flood-control configurations along the Middle Mississippi River (MMR), and 2) assess the relative contributions of various engineered structures and flood-loss strategies to potential flood losses. Assessment of the impact of engineering structures was accomplished by modeling five scenarios for the 100- and 500- year floods: 1) current MMR levee configuration (levee protecting for ≤50-year flood); 2) removal of all flood-control structures on the MMR; 3) increasing the height of levees and floodwalls in metropolitan St. Louis to protect urban areas to the 500-year flood level while simultaneously removing all agricultural levees downstream; 4A) a less engineered MMR channel and floodplain with fewer flood control and navigation structures, simulating conditions from 65 years ago (1942-1947) with 1940's levees; and 4B) a less engineered MMR channel and floodplain with fewer flood control and navigation structures, simulating conditions from 65 years ago (1942-1947) with current levee configuration. Comparison of scenarios 2 and 3 relative to scenario 1 allows for quantitative assessment of the flood-control structures on stages and flood losses. Results from scenario 2 revealed that removing all levees along the MMR reduces the average stages from 2.2 m (100-year) to 2.5 m (500-year, but also increased economic and social impacts relative to scenario 1. Scenario 3 revealed that removing agricultural levees downstream of St. Louis on the MMR decreased stages by 1.4 m (100- and 500-year); however, flood losses for the 100-year flood were increased. Flood losses for the 500-year flood were decreased relative to scenario 1. These results suggest that agricultural levees along the MMR protect against medium size floods (50- or 100-year flood) but cause more damage than they prevent during large floods such as the 500-year flood. Comparison of scenarios 4A and 4B relative to scenario 1 allows for a quantitative assessment of river engineering structures and modern buildings constructed over the last 65 years. In scenarios 4A and 4B, a less engineered river decreased stages by 1.2 m (for the 100-year flood) relative to scenario 1. In scenario 4A, the 1940's levees expose modern buildings in the floodplain to flooding, causing economic building losses to increase; however, in scenario 4B, current levee configuration protects modern buildings in the floodplain from flooding causing, economic building losses to decrease. If the current flood-control structures were not built, it is likely that the land in the floodplain for scenarios 4A and 4B would not be developed and the land used would be more flood-tolerant. Sensitivity analyses were run to assess the impact of using the default HAZUS-MH national-level data; this was done by comparing results produced by using aggregate analysis (coarse data) versus results using UDF analysis (detailed data). The aggregate analysis estimated 51% fewer buildings damaged than the UDF analysis. Conversely, the aggregate analysis increased the economic building losses by 51% relative to the UDF analysis. Although collecting local data for a study is not always feasible, the large differences documented here need to be considered when discussing HAZUS-MH results. Overall, this project shows implications for historic and future flood-control and navigational structure projects on the MMR and other rivers. It also emphasizes the importance of studying the impact future engineering structures will have on water-surface elevations and flood losses before implementing them.

A presente pesquisa concentra-se no estudo hidrológico utilizando o potencial das geotecnologias na modelagem do escoamento na bacia do rio Bengalas, cujo rio principal de mesmo nome, corta o município de Nova Friburgo, RJ, no sentido Sul-Norte. Esse município, um dos mais importantes da região serrana, sofre frequentemente com inundações e deslizamentos, onde, dados históricos e acontecimentos recentes mostram que a ocupação inadequada de encostas e calhas dos rios são as áreas destacada e negativamente afetadas. A metodologia tem suporte no uso de um SIG, extraindo informações, que por sua vez, serão entrada de dados na fase de modelagem, e reforçando a apresentação dos resultados das simulações através de mapas. Ela está divida basicamente em três etapas: "SIG", "Modelagem" e "Suporte à Tomada de Decisão/Simulação". Esse primeiro estudo permitiu compor um banco de dados geográfico com as características fisiográficas da bacia; a seleção criteriosa de uma modelagem matemática e encadeamento de seus parâmetros com os componentes do ciclo hidrológico; realizar a calibração do modelo de transformação chuva-vazão, Soil Conservation Service (CN); e simular a passagem dos volumes gerados pela precipitação efetiva na calha do rio Bengalas, com o objetivo de identificar e analisar as áreas suscetíveis a inundações na porção central da cidade de Nova Friburgo. Modelagem dessa natureza vem sendo empregada, principalmente, no gerenciamento de recursos hídricos, onde a tomada de decisões embasada nos resultados de simulações computacionais, contribuem para evitar prejuízos materiais e financeiros, e ainda, perdas de vidas humanas em áreas de risco, neste caso, aquelas suscetíveis a inundações. Analisando os resultados encontrados temos que a área suscetível à inundação para uma chuva com tempo de recorrência de 50 anos, o mais crítico estudado, seja de aproximadamente 1,0 km, distribuídos nos seus 8,5km na região central de Nova Friburgo-RJ, sendo está, ora delimitada, prioritariamente edificada. / This research focuses on the hydrological study using the potential of geotechnology into runoff modeling of the Bengalas Basin, whose main river, with same name, crosses the city of Nova Friburgo - RJ, in a south-north orientation. This city, one of the most important in "Região Serrana", suffers often with floods and landslides, which, historical data and recent events show that the inappropriate occupation of hillsides and margins of rivers are the highlighted and negatively affected areas. The methodology has basis in a GIS application, extracting information, which in turn, are input in the modeling phase, and enhancing the presentation of simulation results through maps. It is basically divided into three stages: "SIG", "Modelagem" and "Suporte à Tomada de Decisão/Simulação." This first study allowed to compose a geographic database with the physiographic features of the basin; the careful selection of a chain of mathematical modeling and its parameters with the hydrological cycle components, perform the calibration of the rainfall-runoff transformation model, Soil Conservation Service (CN) and simulate the transition of volumes generated by an effective precipitation in the Bengalas river, in order to identify and analyze the susceptible flooding areas in the central part of Nova Friburgo. A kind of this modeling has been used, mainly, in the water resource management, in which decision-making are based on results of computer simulations, helps to avoid a range of losses, such as material, financial and, especially, humans, that in this case, people who lives in areas susceptible to flooding. Analyzing the results, it was found that an area susceptible to flooding by a rainfall with a recurrence time of 50 years, the most critical studied, results in approximately 1.0 km, distributed in its 8.5km (central part of Nova Friburgo - RJ) which this bounded area has a great part with buildings.

nÃo hà / O trabalho apresenta um modelo hidrolÃgico inÃdito para a bacia hidrogrÃfica do rio Granjeiro (BHG), com uma Ãrea de contribuiÃÃo de 18,54 kmÂ, altitude variando de 399 a 953 metros acima do nÃvel do mar, localizada no municÃpio do Crato, regiÃo sul do estado do CearÃ, regiÃo de grande relevÃncia econÃmica no estado, destacando-se o comÃrcio e o turismo. O modelo foi desenvolvido utilizando o software HEC-HMS do Centro de Engenharia HidrolÃgico (CEIWR-HEC), do corpo de engenheiros do exercito dos Estados Unidos da AmÃrica (USACE). A metodologia utilizada foi composta por trÃs partes. A primeira parte tratou de extrair os dados geogrÃficos, fÃsicos e hidrolÃgicos, utilizando modelos digitais de elevaÃÃo, imagens de satÃlites e mapas temÃticos de caracterizaÃÃo territorial do estado do CearÃ, por meio do software ArcGIS e sua extensÃo HEC-GeoHMS, para exportÃ-los para o HEC-HMS. A segunda parte se concentrou na construÃÃo dos hietogramas, utilizando a equaÃÃo de chuva do municÃpio do Crato e o mÃtodo dos blocos alternados. E por fim, na terceira etapa foi simulado o escoamento superficial, provocado por chuvas com vÃrios tempos de retornos, tanto para o cenÃrio atual, quanto para vÃrios cenÃrios fictÃcios da BHG, utilizando o mÃtodo desenvolvido pelo ServiÃo de ConservaÃÃo do Solo (SCS) do Departamento de Agricultura dos Estados Unidos (USDA), conhecido como o modelo SCS. Verificou-se que as Sub-bacias SB4, SB5 e SB9 contribuem com 46% do escoamento total no exutÃrio, alÃm de um crescimento de ocupaÃÃo da BHG em 15%, praticamente dobrarà a probabilidade de cheias no canal do rio Granjeiro, enquanto a diminuiÃÃo desta ocupaÃÃo em 15%, praticamente reduz a possibilidade de cheias no canal do rio Granjeiro pela metade. Contudo, à importante frisar, que o modelo hidrolÃgico apresentado à o primeiro modelo elaborado para a BHG, dando aos gestores municipais do Crato a possibilidade de estudar a construÃÃo de obras hidrÃulicas para contenÃÃo das cheias, alÃm de implementaÃÃo de polÃticas pÃblicas de ocupaÃÃo das Ãreas em contidas na BHG, com o objetivo de reduzir as enchentes ocorridas no canal do rio Granjeiro. / The paper proposes a novel model for hydrological river basin Granjeiro (BHG), with a contribution area of 18.54 kmÂ, altitude ranging 399-953 meters above sea level, located in the county of Crato, southern the state of Cearà of great economic importance in the state, especially trade and tourism. The model was developed using the software HEC-HMS Hydrologic Engineering Center (CEIWR-HEC), the engineer corps of the army of the United States (USACE). The methodology used was composed of three parts. The first part dealt with data extraction geographic, physical and hydrological using digital elevation models, satellite images and thematic maps of territorial characterization of the state of CearÃ, through the ArcGIS software and its extension HEC-GeoHMS to export them for HEC-HMS. The second part focused on building the hietogramas, using the equation of rain Crato and the method of alternating blocks. And finally, the third step was simulated runoff caused by rain several times with returns, both for the current scenario, as for several fictional scenarios BHG, using the method developed by the Soil Conservation Service (SCS) Department of Agriculture (USDA), known as the SCS model. It was found that the sub-basins SB4, SB5 and SB9 contribute 46% of the total flow in river mouth, end an increase in occupancy of BHG 15%, nearly double the likelihood of flooding in the river channel Granjeiro, while this occupation decreased by 15 %, almost reduces the likelihood of flooding in the river channel Granjeiro by half. However, it is important to note that the hydrological model presented is the first model designed for BHG, giving municipal managers Crato the possibility to study the construction of hydraulic containment of floods, as well as implementation of policies of occupation of areas contained in BHG, with the goal of reducing the flooding that occurred in the river channel Granjeiro.

Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-08-28T22:10:21Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Fellipe Henrique Borba Alves.pdf: 14338383 bytes, checksum: 8f642c7124b0b97eb6b6d04da6fc748b (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-09-06T22:01:53Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Fellipe Henrique Borba Alves.pdf: 14338383 bytes, checksum: 8f642c7124b0b97eb6b6d04da6fc748b (MD5) / Made available in DSpace on 2018-09-06T22:01:53Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) DISSERTAÇÃO Fellipe Henrique Borba Alves.pdf: 14338383 bytes, checksum: 8f642c7124b0b97eb6b6d04da6fc748b (MD5) Previous issue date: 2017-02-24 / A Região Nordeste do Brasil é comumente associada às secas prolongadas. No entanto, áreas específicas estão susceptíveis à ocorrência de chuvas intensas, onde podem ser geradas enchentes catastróficas. Nesse contexto, para a bacia do rio Una, em Pernambuco, foi desenvolvido um modelo de previsão de enchentes, capaz de integrar informações de previsão de chuva, modelagem hidrológica e modelagem hidrodinâmica. Neste trabalho buscou-se analisar dados dos modelos de previsão de chuva ETA 40 Km e APAC 9 Km, avaliar a distribuição da vazão gerada através de modelo hidrológico HEC-HMS e testar novos coeficientes de calibração, simular no modelo hidrodinâmico HEC-RAS o efeito da construção de barragens nas cidades de Palmares, Água Preta e Barreiros para o maior evento de chuva já registrado, ocorrido em 2010. Os resultados encontrados indicaram relevante diferença quantitativa e posicional nos dados dos modelos de previsão. O modelo hidrológico HEC-HMS teve melhorias na distribuição de vazão ao longo da bacia e na estabilidade global das vazões geradas. O modelo hidrodinâmico demonstrou redução significativa na vazão de pico a montante das áreas urbanas de Palmares, Água Preta e Barreiros, respectivamente. No entanto, mesmo com redução expressiva de vazão, as inundações nesses municípios ainda podem ocorrer caso eventos semelhantes ao de 2010 venham a acontecer. / Northeast Brazil is commonly associated with prolonged drought effects. However, in specific areas are likely to occur from intense rainfall events, where such events generate catastrophic flooding. In this context, an Advanced Flood Forecasting Model was developed for an Una river basin in Pernambuco, capable of integrating information on rainfall forecasting, hydrological modeling and hydrodynamic modeling. The objective of this work is to analyze the data of the ETA 40 km and APAC 9 km rain forecast models, to evaluate a flow distribution generated through a HEC-HMS hydrological model and to test new calibration coefficients, to simulate in hydrodynamic model HEC-RAS the effect of flood control dams and generate a flood spot in the cities of Palmares, Água Preta and Barreiros, considering the largest rainfall event ever recorded in 2010. The results indicated the quantitative difference and the data of the forecast models, the HEC-HMS hydrological model had improvements in the flow distribution along the basin and in the overall stability of the flows generated, the hydrodynamic model demonstrated a reduction in the upstream peak flow of the urban areas of Palmares, Água Preta and Barreiros, respectively. However, even with expressive flow reduction, such as floods in municipalities can still occur if events similar to the year 2010 occur again.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Recently, engineering researches which deal with urban drainage are proposing the use of computational tools in order to anticipate peak discharges of watersheds and the hydraulic behavior of drainage network system. The use of hydrological and hydraulic computer modeling ensures the minimization of errors in the engineering design process, as well as an increase in quality of the drainage planning work.Therefore, the actual study uses two well know drainage computer codes HEC-HMS and SWMM to design structures to decrease discharge peaks in a watershed situated in a critical area of Fortaleza with respect to floods.This watershed is located west of the city of Fortaleza and at drains the AlagadiÃo stream, which is also the name of the basin. Computer simulation were performed using return periods of 20, 50 e 100 year with and without the presence of dams using both HEC-HMS andSWMM.It was proposed three dams and they were simulated separately and altogether.Result of the simulation showed that the presence of only two dams, caused a significant decrease in flood peaks. According the HEC-HMS this reduction was 24%. According to SWMM, this reduction was 42%. This study is a contribution to the use of computer models in designing urban flood control structures. / Nos Ãltimos anos, pesquisas que envolvem o tema drenagem urbana vÃm introduzindo substancialmente a idÃia do uso de modelos computacionais que simulam os picos de cheias das bacias hidrolÃgicas e o comportamento hidrÃulico da rede de drenagem da bacia. Com o uso da modelagem hidrÃulico-hidrolÃgica podem ser minimizados erros de dimensionamento de projeto, bem como otimizar o planejamento de obras de infra-estrutura com modelos mais detalhados e com menores incerteza, aumentando o nÃvel de confiabilidade da obra. Assim sendo, nesta pesquisa foram escolhidos dois softwares, jà bastante conceituados nos estudos de drenagem urbana, o HEC-HMS e o SWMM, para a anÃlise das suas aplicabilidades no estudo hidrÃulico-hidrolÃgico de amortecimento de cheias em uma das Ãreas crÃticas sujeitas a alagamento no municÃpio de Fortaleza. A Ãrea està localizada a oeste da cidade, e à delimitada pelas Ãreas de contribuiÃÃo do riacho AlagadiÃo, que dà nome a bacia do estudo. Intencionando a atenuaÃÃo dos picos de chuva da Ãrea, foram feitas simulaÃÃes com e sem o uso de reservatÃrios de detenÃÃo para os tempos de recorrÃncia de 20, 50 e 100 anos. Para tanto foram testados o uso de trÃs reservatÃrios em possÃveis pontos de acoplamento, onde foram feitas aplicaÃÃes sem o uso de reservatÃrios, com o uso dos trÃs reservatÃrios separadamente, em pares e em conjunto os trÃs. Dos resultados, observou-se que apenas dois dos reservatÃrios obtiveram uma diminuiÃÃo considerÃvel para a minimizaÃÃo dos problemas de inundaÃÃo da bacia do riacho AlagadiÃo, sendo obtida uma reduÃÃo do pico de cheias de atà 24%, segundo os resultados do HEC-HMS e 42% pelos dados do SWMM, utilizando os dois em conjunto. Por fim, confirma-se a credibilidade no uso das ferramentas computacionais HEC-HMS e SWMM em obras de infra-estrutura urbana, com nÃveis bastante relevantes de detalhamento da bacia. Este estudo à um passo inicial para o desenvolvimento de novos projetos de infra-estrutura como o uso de modelos computacionais hidrÃulico-hidrolÃgicos.

The aim of this study was to model if hydraulically suitable habitats for juvenile and spawning grayling could be created by morphological restoration alone in the Bjurfors Övre hydropower outlet channel in the Ume River Basin. The study was done by 2D modelling with HEC-RAS using hourly water flow and level data collected during the period 20160521-20161029. Suitable water depth and velocity values for larvae and spawning grayling were collected from literature. Environmental measures for the Bjurfors Övre outlet channel were designed based on the morphology in outlet channels with documented reproducing grayling populations and large habitat diversities. The outlet channel at present morphology and after morphological modifications were modelled at different flow scenarios (0-369m3/s) and areas of suitable water velocities and depths before and after proposed measures were compared. Results show that suitable velocity areas would increase with a factor of between 1,03-1,81 and the suitable depth areas with a factor of 2,34-19,09 and that suitable depths may be the major limiting factor in current conditions. Results also show that zero-flow events at Bjurfors Övre hydropower plant create unsuitable velocities for larvae and spawning grayling and that the frequency and duration of such events could be more limiting than the mere occurrence of such events. The study indicates that the morphological restoration in hydropeaking outlet channels could improve the availability of habitats with suitability water depth and velocity not only for larvae and spawning grayling, but for other lotic organisms. The study also showed that HEC-RAS modelling is a potential resource effective way to assess to what extent certain proposed environmental measures may create suitable water depths and velocities in hydropeaking outlet channels.