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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

PrePro2004: a data model with pre and post-processor for HEC-HMS

Agrawal, Ashish 01 November 2005 (has links)
This thesis presents the design concepts and development of an interface (Pre- Pro2004) utilizing geodatabases for the Hydrologic Modeling System (HMS) of the Hydrologic Engineering Center (HEC). HMS is a rainfall-runoff model which supports lumped-parameter as well as distributed-parameter based modeling. PrePro2004 uses the spatial-analysis as well as data handling capabilities of ArcGIS. The spatial data are processed to create input files for HMS. These input files and the output from HMS are stored in two geodatabases which were developed using data model concepts. The tools are provided to reproduce an HMS model from the data inside these geodatabases. The interface is developed based on the DataCentric approach which brings different hydrologic and hydraulic models together. This approach aims to attain a long-term goal of utilizing the same data for different hydrologic or hydraulic models with additional model specific requirements. Two case studies are presented to show the applications of the tools developed. The first case study details the creation of HMS input files for Salado Creek watershed with Digital Elevation Model as input. It includes the importation of an existing HMS model for Salado Creek watershed as Appendix C. The second case study details the creation of HMS input files for the Bull Creek watershed, with land use and soil type data as inputs. It describes the capabilities of tools developed in detail.
2

Studie srážko-odtokových poměrů pro územní plán obce Václavov

Kmeť, Milan January 2012 (has links)
No description available.
3

Avaliação da Vulnerabilidade de Barramentos ao Rompimento de pequenos barramentos localizados a montante / Assessing the vulnerability of dams to the breaking of small reservoirs located upstream

MENDES, Thiago Augusto 22 August 2008 (has links)
Made available in DSpace on 2014-07-29T15:01:53Z (GMT). No. of bitstreams: 1 Dissertacao Thiago Augusto Mendes.pdf: 1579754 bytes, checksum: 97b3cf99f922e3e8f0387617e13d2db4 (MD5) Previous issue date: 2008-08-22 / In spite of Brazil being the country with one of the largest quantities of dams on the planet, there is no study that confront the influence of small dams collapse on major dams. This is very important from a strategic and planning point of view, since much of the energy produced in the country comes from hydroelectric installed in rivers. Althought the hydroelectric sizing is done following strict security techniques, the upstream reservoirs, in most cases are not. This factor leads to great uncertainty about safety of these dams. Thus, this work is important to the development of a methodology able to quantify how small dams affect the safety of large dams. The purpose was set a vulnerability rate to disruption of these small dams, thereby providing data for municipal, state and federal entities about the real situation for granting, construction and operation of dams. The determination of vulnerability rate was made with simulations conducted in the HEC-HMS hydrological model, thereby determining the additional flow from the disruption of dams along the upstream of the dam under study. The study site chosed was the basin of the Meia Ponte river - GO, precisely the Rochedo s hydroelectric, where 30 reservoirs were evaluated for disruption. It was found that the flow that reaches the Rochedo s reservoir, without considering the disruption of reservoirs located upstream (1.222 m³/s) for a return period of 10,000 years is about 31% higher than the flow planned for Rochedo, that is 935 m³/s, as informed by the Energy Company of Goiás (CELG, 2008). The calculated vulnerability rate was 1,31 for a return period of 10,000 years without considering the disruption of the upstream reservoirs and were suitable for a reservoir that was built in the 50's. However the flow that reaches the Rochedo s reservoir, considering the disruption of the upstream reservoirs for a return period of 10,000 years (1.880 m3/s) is much higher than flow considered without disruption of the upstream reservoirs. The calculated vulnerability rate goes to 1,54 for a return period of 10,000 years, wich is considered a high value that deserves care assessment / Apesar do Brasil ser o país com uma das maiores quantidades de barramentos do planeta, não existe um estudo que seja de conhecimento desse autor, que confronte a influência do colapso dos pequenos barramentos sobre grandes represas. Este aspecto é muito importante do ponto de vista estratégico e de planejamento, uma vez que boa parte da energia produzida no país vem das hidroelétricas instaladas em rios. Embora estas hidroelétricas tenham o seu dimensionamento feito seguindo rigorosas técnicas de segurança, os armazenamentos em reservatórios de montante, na maioria dos casos não o são. Este fator leva a uma grande incerteza quanto ao nível de segurança destas barragens. Dessa forma, este trabalho terá importância no desenvolvimento de uma metodologia capaz de quantificar o quanto as pequenas barragens afetam a segurança das grandes barragens. O objetivo foi definir um índice de vulnerabilidade ao rompimento dessas pequenas barragens, ajudando assim os órgãos municipais, estaduais e federais a constatar a real situação para outorga, construção e operação de barragens. A determinação do índice de vulnerabilidade será feita a partir de simulações realizadas com o modelo hidrológico HEC-HMS, determinando assim o acréscimo de vazão proveniente do rompimento das barragens localizadas à montante da barragem em estudo. O local de estudo escolhido foi a bacia hidrográfica do rio Meia Ponte - GO, precisamente a usina hidroelétrica de Rochedo, onde 30 barramentos foram avaliados para o rompimento. Verificou-se que a vazão que chega ao reservatório de Rochedo sem considerar o rompimento dos barramentos localizados à montante (1.222 m³/s) para um período de retorno de 10.000 anos é cerca de 31% maior que a vazão planejada para Rochedo, que no caso é de 935 m³/s, conforme informação fornecida pela Companhia Energética de Goiás (CELG, 2008). O índice de vulnerabilidade calculado foi de 1,31 para um período de retorno de 10.000 anos sem considerar o rompimento dos barramentos à montante, mostrando-se adequado para um reservatório que foi construído na década de 50. Já a vazão que chega ao reservatório de Rochedo, considerando o rompimento dos barramentos à montante para um tempo de retorno de 10.000 anos (1.880 m3/s) é muito superior à vazão considerada sem o rompimento dos barramentos à montante. O índice de vulnerabilidade calculado passa a ser de 1,54, para um período de retorno de 10.000 anos, considerado um valor alto merecendo cuidados de avaliação.
4

Coupled Surface Water-Groundwater Model to Analyze Sustainability of the Atascadero Subbasin

Klinchuch, Matthew Timothy 01 June 2012 (has links)
The Atascadero Subbasin, located on the central coast of California, is a small, hydraulically separated sub-region of the Paso Robles Groundwater Basin. Three local cities operate approximately 40 wells to pump the Subbasin for their entire water supply needs. Past studies have questioned sustainability of the Subbasin as the combined pumping rate by the three cities is nearing the perennial yield of the Subbasin. The studies have been inconclusive as some areas of the Subbasin have seen increases in water table elevation thus questioning the assessment that consumption is nearing perennial yield. The objective of this research was to perform a water balance study for the aquifer and examine sustainability of the Subbasin. Surface water and groundwater models were developed to investigate the interaction between the Salinas River Alluvium Soils and the deeper Paso Robles Formation based on pumping from different shallow and deep wells. Surface water hydrology of the Subbasin was studied using HEC-HMS, and Visual MODFLOW was used to model the aquifer. Both HEC-HMS and Visual MODFLOW was calibrated to improve simulation accuracy. HEC-HMS was used to quantify natural recharge to the aquifer and to simulate streamflow and water level for the Salinas River. HEC-GeoHMS was used to delineate the watershed, create sub-watersheds and channel networks, and to extract sub-watershed inputs that were used to build HEC-HMS from geospatial data including land use, soil and topography data. Different hydrogeologic layers were defined to represent the alluvium and deeper soils. Results show that currently the Atascadero Subbasin does not appear to be in overdraft as shallow groundwater wells pump Salinas River underflow and the alluvium appears to be providing some recharge to the deeper aquifer. These findings would provide municipal and water managers better understanding of where their water comes from, the effects of their pumping, and could help with developing sustainable management strategies for the Subbasin.
5

Estimating Upper Red Butte Watershed Contribution to Salt Lake Valley Water Resources

Limbu, Sal Bir 01 May 2019 (has links)
Water is crucial for domestic, agricultural, industrial, environmental, and hydropower uses. Once precipitation occurs, it eventually partitions into streamflow, evapotranspiration (ET), and groundwater recharge. Distribution of precipitation into these partitions is called a hydrologic budget. The hydrologic budget of any geographic area or watershed under different climate change conditions help water managers to make appropriate water management plans. Computer based hydrologic modeling software has been used extensively to solve many water resources problems including hydrologic budgets. Hydrologic modeling requires high quality weather parameter data. This study projected surface and groundwater flows from the portion of RBC watershed that lies above Red Butte Reservoir (RBR) to Salt Lake Valley (SLV) for water years (WYs) 2051-2060 in two climatic Representative Concentration Pathways (RCPs) scenarios, RCP 4.5 and RCP 8.5. RCP 8.5 corresponds to the pathways with higher greenhouse gas emission than RCP 4.5. To project flows, we first used Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) 4.3 model to calibrate and validate the observed streamflow for WYs 2016 and 2017 respectively. However, within RBC study area weather stations, all three weather parameters (Precipitation (P), Temperature (T), and Net Radiation (NR)) required for HEC-HMS model were missing on the same day for some periods of WYs 2016-2017. This necessitated to fill the missing parameters prior to the model calibration and validation. We hypothesized that systematically using ANN and SMs would enable making accurate estimates, even when multiple parameter values are missing on the same day. The hypothesis-estimated the missing weather parameters (P, T, and NR) values are useful for hydrologic modeling in a watershed. We ran the HEC-HMS validated model for WY 2051-2060 once for each RCP scenario, and quantified the flows to SLV. The model results showed that average stream and groundwater flows of WYs 2016 and 2017 were 14.1% and 55.7% of total study area precipitation, respectively. In the future 2051- 2060, compared with average annual surface and groundwater flows of WYs 2016-2017, percent changes in flows, respectively, were i) decreases of 29.6% and 24.2% for RCP 4.5 and ii) decreases of 26% and 23.9 % for RCP 8.5.
6

ANALYZING THE EFFECTS OF CLIMATE CHANGE ON URBAN STORMWATER INFRASTUCTURES

Thakali, Ranjeet 01 May 2017 (has links)
The change in the hydrological cycle due to climate change entails more frequent and intense rainfall. As a result, urban water systems will be disproportionately affected by the climate change, especially in such urban areas as Las Vegas, which concentrates its population, infrastructure, and economic activity. Understanding the proper management of urban stormwater in the changing climate is becoming a critical concern to the water resources managers. Proper design and management of stormwater facilities are needed to attenuate the severe effects of extreme rainfall events. In an effort to develop better management techniques and understanding the probable future scenario, this study used the high-resolution climate model data conjunction with advanced statistical methods and computer simulation. Las Vegas Valley which has unique climatic condition and is surrounded by the mountains in every direction was chosen for the study. The North American Regional Climate Change Assessment Program is developing multiple high-resolution projected-climate data from different combinations of regional climate models and global climate models. First, the future design depths was calculated using generalized extreme value method with the aid of L-moment regionalization technique. The projected climate change was incorporated into the model at the 100 year return period with 6h duration depths. Calculation showed that, the projection from different sets of climate model combinations varied substantially. Gridded reanalysis data were used to assess the performance of the climate models. This study used an existing Hydrologic Engineering Center’s Hydrological Modeling System (HEC-HMS) model and Storm Water Management Model (SWMM) developed by the Environmental Protection Agency (EPA) were implemented in the hydrological simulation. Hydrological simulation using HEC-HMS showed exceedances of existing stormwater facilities that were designed under the assumption of stationarity design depth. Low Impact Developments such as permeable pavement and green roof were found to be effective in the attenuation of climate change induced excess surface runoff. The primary purpose of this study is understanding of proper designing, planning and management of the urban stormwater system in the predicted climate scenarios.
7

AVALIAÇÃO DE VAZÕES MÁXIMAS ESTIMADAS A PARTIR DOS MODELOS HEC-HMS E SWMM ESTUDO DE CASO PARA O NÚCLEO URBANO E REGIÃO PERIURBANA DE MUNIZ FREIRE

SOUZA, T. C. T. 04 August 2017 (has links)
Made available in DSpace on 2018-08-01T23:59:24Z (GMT). No. of bitstreams: 1 tese_11471_Dissertação - Tainah de Souza CD.pdf: 4931542 bytes, checksum: fab9c37691c8c2445e4f9540b0310b3e (MD5) Previous issue date: 2017-08-04 / A determinação da vazão de projeto constitui etapa fundamental para o adequado dimensionamento de obras de drenagem ou para possibilitar a adequada tomada de decisão sobre medidas não estruturais relacionadas com a drenagem pluvial. Em regiões que não dispõem de dados fluviométricos recorre-se, usualmente, à utilização dos modelos do tipo chuva-vazão para determinação indireta da vazão de projeto. Função da diversidade de modelos disponíveis, cabe ao modelador a escolha do modelo mais adequado às singularidades da área avaliada, permitindo a produção de resultados que se apresentem mais próximos da realidade. Neste estudo foi realizada a análise comparativa dos modelos Storm Water Management Model (SWMM) e Hydrologic Engineering Center - Hydrologic Modeling System (HEC-HMS) quando da estimativa de vazões máximas associadas ao núcleo urbano e regiões periurbanas do município de Muniz Freire (ES). A estimativa do escoamento superficial foi realizada através do método Hidrograma Unitário e as perdas de infiltração pelo método SCS Curve Number. A equação de chuvas intensas foi apropriada através do método de Chow-Gumbel e a chuva de projeto pelo método dos blocos alternados. Os modelos apresentaram relevantes diferenças nos valores de vazão de pico e volume de escoamento superficial. Para períodos de retorno entre 2 e 5 anos, os valores de vazão de pico e volumes de escoamento superficial estimados pelo SWMM apresentaram-se superiores aos obtidos pelo HEC-HMS para todas as bacias avaliadas, invertendo-se esta tendência com o aumento do período de retorno. As simulações associadas aos períodos de recorrência de 10 e 20 anos, usualmente utilizados em estudos e projetos de drenagem urbana, foram as que se apresentaram mais próximas, com as menores diferenças relativas para as variáveis hidrológicas avaliadas.
8

Assessing the ability of HEC-HMS rainfall-runoff model to simulate stream flow across Sweden

Alavimoghaddam, Mohammadreza January 2017 (has links)
Computer modeling is the powerful tool for simulating nature’s behavior; however, still more efforts are need for reaching perfect simulation with computer models (especially in the hydrological field of study). In this Master’s thesis, the accuracy of the HEC-HMS computer model for long term rainfall-runoff simulation was evaluated across Sweden. Five different catchments from north to south of Sweden were selected and then simulation have done for 34 years of available data. Simulation was conducted using daily, monthly and yearly time scale resolutions. Results from the north to the south of Sweden were completely different. Simulated runoff and observed runoff in northern catchments followed the same pattern over different time scales but in the southern part of Sweden the results had different patterns in space and time. The best results with HEC-HMS were found in the northern catchments with steep main river slopes. In the southern catchments the model could not predict runoff in any realistic manner at any time and space scale. In total the HEC-HMS model cannot simulate the rainfall runoff for long periods of simulation across Sweden. This is especially true in southern parts of the country dominate with low elevation catchments. However, with regards to its ability for event-based simulation HEC-HMS could be a suitable tool to simulate flood event discharges that are needed for road or other hydraulic structures designs. But, this would require significant amounts of calibration and model development.
9

Distributed storage modeling in Soap Creek for flood control and agricultural practices

Wunsch, Matthew John 01 May 2013 (has links)
In 1988, the counties of Appanoose, Davis, Monroe, and Wapello created the Soap Creek Watershed Board. This group put in place a plan to fund and construct 154 farm ponds in an effort to provide water for agriculture practices as well as provide flood protection for the residents inside the Soap Creek watershed. Through collaborative efforts and funding from federal, state, and local sources, to date 132 ponds have been constructed. Currently there is no stream monitoring in place in the watershed to observe stream conditions. This leads to no stored data on the benefits of the projects in the basin and the reduced flood impacts. With funding from the Iowa Watershed Projects (IWP) through the IIHR - Hydroscience & Engineering lab, a lumped parameter surface water model was created to show the benefits of the constructed projects. Using detailed LiDAR data, a Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) model was created. This model used arcHydro and ARC-GeoHMS, tools in ARCgis. Detailed LiDAR, SURGGO soil data, and land cover data was used to create the model parameters. Several design and historical storms were modeled to quantify the benefits in peak flow reductions and in amounts of water stored behind the projects.
10

Modeling Flood Reduction Scenarios for a Small Coastal Community

Perez, Evan J. 01 March 2013 (has links) (PDF)
The Arroyo Grande Creek Watershed, an approximately 170 mi2 watershed located on the central coast of California, drains to the Pacific Ocean via the Arroyo Grande Creek that passes through several coastal cities including the community of Oceano. At the mouth of the Creek is the Arroyo Grande Lagoon, which is connected to another lagoon known as the Oceano Lagoon, by a tidal flap-gate whose hydraulics is a function of water levels in the two lagoons. Historically the Oceano Lagoon has played a part in floods that have occurred in the community of Oceano. The most recent flooding occurred in 2010 when a storm with about a10-yr frequency caused flooding that led to an estimated property damage of about two million dollars. This study was conducted to understand hydrology of the Arroyo Grande watershed that also feeds Lopez Lake, a reservoir that provides water for drinking, agriculture, and environmental flows; to characterize hydraulics of the Oceano Lagoon; and to explore scenarios for flood mitigation. Objectives of the study are to provide a better understanding of the causes of the historical floodings; map the extent of floodings for various storm events including 10 year, 50 year, and 100 year under current conditions; and examine potential solutions to reduce future floodings. Surface water hydrology of the Arroyo Grande Creek Watershed was studied using HEC-HMS to quantify runoff specifically into the Oceano Lagoon. HEC-HMS was calibrated using known streamflow to improve the accuracy of the model. The HEC-HMS model was developed using spatial data that was organized in ArcMAP. Data such as elevation, land use, soil type, and impervious surface were processed using HEC-GeoHMS and exported to HEC-HMS. Mitigation measures were simulated in HEC-HMS by adjusting parameters such as the outlet configuration and the increased volume in Oceano Lagoon. Each mitigation measure delivered varying effectiveness. Results show that while the peak flow and volume in the lagoon can be reduced, larger design storms will continue to inundate the area unless drastic steps are taken. The findings could assist local flood control agencies by evaluating the risks of continuing to use the existing drainage system, and identifying opportunities available to reduce those risks.

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