This document summarizes a thesis that models stormwater infiltration in roadside swales. The model routes flow over a fraction of the swale slope using a "fractionally wetted area" parameter, rather than assuming sheet flow. It uses the Green-Ampt infiltration equation and numerical solutions of overland flow equations. The model was developed in Matlab and its results were compared to three flume studies and a field experiment, showing the model's accuracy is limited by soil parameter inputs.
This document provides guidance on using the area-slope method to estimate stream discharge indirectly when direct measurement is not possible. It describes the principles and steps of the area-slope method, including selecting a study reach, measuring the cross-sectional area and water surface slope, evaluating velocity using Manning's formula, and computing discharge. Guidelines are given for selecting sites, measuring cross-sections and slope, determining roughness coefficients, and performing calculations. The area-slope method provides a rough estimate of discharge but has limitations due to uncertainties in roughness coefficients.
Mathematical modeling approach for flood managementprjpublications
This document summarizes the development of a mathematical model for flood management in the Godavari River basin in India using the MIKE 11 software. The model is calibrated using data from 2009-2011 and validated against data from 2012. Real-time validation is also conducted during floods in 2013. Results show good agreement between measured and computed river stages, indicating the model can accurately forecast river levels for flood management.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Abstract Urban watersheds produce an instantaneous response to rainfall. That results in stormwater runoff in excess of the capacity of drainage systems. The excess stormwater must be managed to prevent flooding and erosion of streams. Management can be achieved with the help of structural stormwater Best Management Practices (BMPs). Detention ponds is one such BMP commonly found in the Austin, TX, USA. The City of Austin developed a plan to mitigate future events of flooding and erosion, resulting in the development and integration of stormwater BMP algorithms into the sub-hourly version of SWAT model. This paper deals with the development of a physically based algorithm for detention pond. The algorithm was tested using a previously flow-calibrated watershed in the Austin area. From the test results obtained it appears that the detention pond algorithm is functioning satisfactorily. The algorithm developed could be used a) to evaluate the functionality of individual detention pond b) to analyze the benefits of such structures at watershed or higher scales and c) as design tool. Keywords: flooding, detention, urban, watershed, BMP, algorithm, stormwater, modeling
The document describes a proposed Monte Carlo framework for estimating design floods in the Brisbane River catchment in Australia. The framework would (1) generate synthetic flood events by sampling probabilities of factors like rainfall and reservoir levels, (2) use rainfall intensity data and spatial patterns to estimate rainfall for sub-catchments, (3) model runoff and routing through the catchment using a hydrological model, and (4) estimate flood levels, discharges and volumes at different locations and return periods through post-processing of model results. The framework aims to better represent the variability and interactions of all flood influencing factors compared to traditional methods.
This document provides information about a training module on understanding stage-discharge relations being conducted by the Central Water Commission of India. The training is aimed at middle level engineers and will cover topics like correlation and regression analysis, classification of controls, characteristics of rating curves, extrapolation of rating curves, and shifts in discharge ratings. The module will be 90 minutes long and use methods like lectures, discussions and questioning. The objectives are to help officers understand stage-discharge relations and impart this training to supervisors and junior staff.
This document describes a training module on establishing stage-discharge rating curves. It includes sections on the general concept of rating curves, types of station controls, and methods for fitting rating curves. Rating curves relate river stage to discharge and are established by collecting concurrent stage and discharge measurements over a range of river levels. The shape and reliability of the rating curve depends on the station control, which is a reach or section of channel that controls flow. Fitting rating curves requires understanding channel characteristics and controls as well as applying mathematical and graphical techniques.
This document presents a case study of coupling surface water and groundwater models in the Netravathi river basin located in southern India. It summarizes the data collected and methodology used. Key data included a digital elevation model, soil data, land use/land cover maps, rainfall and weather data, hydrological data including streamflow, and groundwater levels. The methodology involved using SWAT to model surface water hydrology and estimate groundwater recharge, then coupling the SWAT outputs to a MODFLOW groundwater model to allow a more complete analysis of the regional hydrological system.
This document provides guidance on using the area-slope method to estimate stream discharge indirectly when direct measurement is not possible. It describes the principles and steps of the area-slope method, including selecting a study reach, measuring the cross-sectional area and water surface slope, evaluating velocity using Manning's formula, and computing discharge. Guidelines are given for selecting sites, measuring cross-sections and slope, determining roughness coefficients, and performing calculations. The area-slope method provides a rough estimate of discharge but has limitations due to uncertainties in roughness coefficients.
Mathematical modeling approach for flood managementprjpublications
This document summarizes the development of a mathematical model for flood management in the Godavari River basin in India using the MIKE 11 software. The model is calibrated using data from 2009-2011 and validated against data from 2012. Real-time validation is also conducted during floods in 2013. Results show good agreement between measured and computed river stages, indicating the model can accurately forecast river levels for flood management.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Abstract Urban watersheds produce an instantaneous response to rainfall. That results in stormwater runoff in excess of the capacity of drainage systems. The excess stormwater must be managed to prevent flooding and erosion of streams. Management can be achieved with the help of structural stormwater Best Management Practices (BMPs). Detention ponds is one such BMP commonly found in the Austin, TX, USA. The City of Austin developed a plan to mitigate future events of flooding and erosion, resulting in the development and integration of stormwater BMP algorithms into the sub-hourly version of SWAT model. This paper deals with the development of a physically based algorithm for detention pond. The algorithm was tested using a previously flow-calibrated watershed in the Austin area. From the test results obtained it appears that the detention pond algorithm is functioning satisfactorily. The algorithm developed could be used a) to evaluate the functionality of individual detention pond b) to analyze the benefits of such structures at watershed or higher scales and c) as design tool. Keywords: flooding, detention, urban, watershed, BMP, algorithm, stormwater, modeling
The document describes a proposed Monte Carlo framework for estimating design floods in the Brisbane River catchment in Australia. The framework would (1) generate synthetic flood events by sampling probabilities of factors like rainfall and reservoir levels, (2) use rainfall intensity data and spatial patterns to estimate rainfall for sub-catchments, (3) model runoff and routing through the catchment using a hydrological model, and (4) estimate flood levels, discharges and volumes at different locations and return periods through post-processing of model results. The framework aims to better represent the variability and interactions of all flood influencing factors compared to traditional methods.
This document provides information about a training module on understanding stage-discharge relations being conducted by the Central Water Commission of India. The training is aimed at middle level engineers and will cover topics like correlation and regression analysis, classification of controls, characteristics of rating curves, extrapolation of rating curves, and shifts in discharge ratings. The module will be 90 minutes long and use methods like lectures, discussions and questioning. The objectives are to help officers understand stage-discharge relations and impart this training to supervisors and junior staff.
This document describes a training module on establishing stage-discharge rating curves. It includes sections on the general concept of rating curves, types of station controls, and methods for fitting rating curves. Rating curves relate river stage to discharge and are established by collecting concurrent stage and discharge measurements over a range of river levels. The shape and reliability of the rating curve depends on the station control, which is a reach or section of channel that controls flow. Fitting rating curves requires understanding channel characteristics and controls as well as applying mathematical and graphical techniques.
This document presents a case study of coupling surface water and groundwater models in the Netravathi river basin located in southern India. It summarizes the data collected and methodology used. Key data included a digital elevation model, soil data, land use/land cover maps, rainfall and weather data, hydrological data including streamflow, and groundwater levels. The methodology involved using SWAT to model surface water hydrology and estimate groundwater recharge, then coupling the SWAT outputs to a MODFLOW groundwater model to allow a more complete analysis of the regional hydrological system.
This document discusses the role of information and communication technologies (ICT) in education, using Indira College in Pune, India as a case study. It is divided into four sections. The first section defines ICT and reviews literature on its use in education. ICT is shown to improve the flexibility and accessibility of education by allowing learners to access knowledge anytime, anywhere. The second section explores how ICT enhances teaching, learning, and motivation by supporting student-centered learning. The third section outlines advantages like supporting competency-based curricula. The fourth section examines ICT's role at Indira College specifically. In summary, the document analyzes how ICT improves education through increased flexibility, accessibility, and support for
This document summarizes a study on rehabilitation facilities provided by the Indian government for people with disabilities.
The study analyzed census data showing that over 26.8 million Indians, or 2.2% of the population, have a disability. In Pune, around 200,000 people, or 2.2% of the population, have a disability.
The government provides various schemes including 3% reservation in government jobs, scholarships for education, financial assistance for self-employment, aids/appliances, and transportation concessions. However, the study found awareness of these facilities is still low in society based on a survey of 127 people in Pune.
The study aims to evaluate the need for rehabilitation, analyze government
Este documento proporciona una guía de las mejores actividades, playas y restaurantes para una estancia de 7 días en Menorca. Presenta dos playas importantes, Cala Presili y Cala Tortuga, y lista las 10 mejores actividades deportivas, que incluyen snorkel, buceo, flyboard y parapente. Además, identifica dos lugares para ver puestas de sol espectaculares, Punta Nati y Caballería, y sugiere comprar quesos, vinos y dulces locales. Finalmente, recomienda dos restaurantes,
Change management by neurological aspects of organizational behaviourIAEME Publication
This document summarizes a research study on how neurological aspects impact organizational behavior and change management. The study examined how changes can influence employee performance, decision-making, teamwork, creativity and engagement. It surveyed 40 small and medium enterprises to understand their perspective on neurology and behavior correlations. The study aims to formulate effective change management policies considering probable deviations in behavior caused by neurological stimuli. Key findings suggest training and experience can improve ethical sensitivity, which influences behavior through neurological aspects. Engaged employees show higher cognitive function, social skills and self-regulation through certain brain networks. High-performing workplaces consider elements like job design and leadership that motivate commitment and focus on results.
Marketing strategy for profit maximization and increase in market shareIAEME Publication
This document summarizes a case study analyzing the marketing strategy of a toothbrush producing company in India. The company saw a drop in profits from the first to second quarter of 2013. The authors analyzed cost and revenue data to determine the reason for the drop was a decrease in sales. They then proposed two strategies to increase profits and market share: 1) Lower prices by 4% to increase sales by 20% or 2) Lower prices by 3.04% to reach the breakeven point and gain market share without risking price competition. Both strategies were shown to increase profits over the first quarter. Additionally, a new tongue cleaner product was proposed to enter new market segments using Ansoff's matrix and a Five Forces analysis to
Imagine 2014: The Devil is in the Details How to Optimize Magento Hosting to ...George White
The document discusses optimizing Magento hosting to increase online sales. It describes a case study of a travel website that experienced a catastrophic event due to a locked database from high query volumes. The root cause was identified and a solution was implemented using a "McManus Magic Shield" to block cache rebuilds if one was already in progress. Load testing results showed that code quality and site configuration are major factors in Magento performance. Best practices for development like reducing requests and using caching can significantly improve scalability. Faster page loading directly correlates to increased conversion rates.
Sequence diagram menggambarkan interaksi antar objek dalam sistem berupa pesan yang ditunjukkan terhadap waktu, dimulai dari trigger aktivitas, proses internal, dan output. Diagram ini terkait dengan use case diagram untuk menunjukkan tahapan dalam suatu use case. Contoh diagram menggambarkan proses penggajian dan pendaftaran pelanggan PLN.
A study on passenger’s satisfaction towards railway services in erode junctionIAEME Publication
This document summarizes a research study on passenger satisfaction with railway services in Erode Junction, India. The key points are:
1. The study used a survey method to assess passenger satisfaction across 7 railway services on factors like tangibles, empathy, assurance, comfort, frequency, reliability, and speed.
2. The results found that 83.8% of passengers were dissatisfied with services, with comfort ranked as the most important service and reliability as the least important.
3. Recommendations to improve passenger awareness included better signage about services, regular announcements, and printing service details on tickets.
Este documento presenta un libro de matemáticas para cuarto grado que incluye ejercicios de cálculo mental, números romanos y conversiones de unidades de medida. El libro contiene preguntas de opción múltiple sobre sumas, restas, multiplicaciones y conversiones de unidades, con instrucciones para que los estudiantes resuelvan los problemas mentalmente.
Az előadás a Tanárszakos hallgatók projektbemutatói - Intel® Teach Essentials a felsőoktatásban c. szekcióban hangzott el. Bajnai Edina a Debreceni Egyetem tanárszakos hallgatója. Projektportfóliójáról több olvasható ebben a cikkben: http://hirmagazin.sulinet.hu/hu/pedagogia/projektportfolio-gondolatolvasas-gesztusokbol-kepekbol, illetve a portfólió teljes egészében megtekinthető a Sulinet.hu-n a Kontextus csoport dokumentumtárában. (A dokumentumok megtekintéséhez az oldalon való regisztráció és a csoportba való belépés szükséges.)
O documento fornece informações sobre o contexto histórico e geográfico no qual Saulo nasceu e cresceu. Resume a história da Cilícia e de Tarso, descreve a estrutura política do Império Romano na época e a situação das províncias sob domínio romano. Também discute a diáspora judaica e o trabalho das entidades espirituais para promover a fraternidade entre os povos do Império.
Economic indicators and stock market performance an empirical case of indiaIAEME Publication
This document summarizes a study that examines the relationship between various economic indicators and stock market performance in India from 1998 to 2014. It finds that GDP growth, gross domestic savings, and gross capital formation have a positive influence on the BSE Sensex, while inflation, exchange rates, interest rates, unemployment, and FDI do not. A regression model is developed that explains 77.2% of the variability in stock market performance based on these economic factors. The study thus provides evidence that certain macroeconomic variables influence long-term stock prices in the Indian market.
Employee mentoring a training and development technique in enhancing organiz...IAEME Publication
This document summarizes an article from the International Journal of Management about employee mentoring. It discusses mentoring as a training and development technique to enhance organizational effectiveness and efficiency. The document provides an overview of mentoring and examines its benefits to both mentees and mentors. It also explores several theories of mentoring and provides conceptual clarifications of mentoring. The key findings are that mentoring can improve both individual and organizational effectiveness, and that it benefits the mentee, mentor and organization.
This document describes the development of a groundwater elevation surface and scoring system for sanitary sewer pipes in Mecklenburg County, North Carolina. The author modeled several potential groundwater elevation rasters using different datasets and methods, including using an existing USGS raster, replicating the USGS methodology with new local data, inverse distance weighted interpolation of local well and stream data, and regression analysis of local elevation, slope, and groundwater data. Pipes were then scored based on their material, the volume of sewage carried, and their position relative to the selected groundwater elevation raster. The scores identified pipes at risk of sewage exfiltration or groundwater infiltration to prioritize rehabilitation efforts.
Review of Groundwater Surfacewater Interaction Modelling Sofware Approaches ...eWater
This report presents the outcomes of a review of the available approaches for modelling groundwater–surfacewater interactions at various spatial and temporal scales with different levels of complexity. It is aimed at determining the deficiencies of the current water modelling approaches for Australian conditions and making recommendations for future model development.
This document discusses the role of information and communication technologies (ICT) in education, using Indira College in Pune, India as a case study. It is divided into four sections. The first section defines ICT and reviews literature on its use in education. ICT is shown to improve the flexibility and accessibility of education by allowing learners to access knowledge anytime, anywhere. The second section explores how ICT enhances teaching, learning, and motivation by supporting student-centered learning. The third section outlines advantages like supporting competency-based curricula. The fourth section examines ICT's role at Indira College specifically. In summary, the document analyzes how ICT improves education through increased flexibility, accessibility, and support for
This document summarizes a study on rehabilitation facilities provided by the Indian government for people with disabilities.
The study analyzed census data showing that over 26.8 million Indians, or 2.2% of the population, have a disability. In Pune, around 200,000 people, or 2.2% of the population, have a disability.
The government provides various schemes including 3% reservation in government jobs, scholarships for education, financial assistance for self-employment, aids/appliances, and transportation concessions. However, the study found awareness of these facilities is still low in society based on a survey of 127 people in Pune.
The study aims to evaluate the need for rehabilitation, analyze government
Este documento proporciona una guía de las mejores actividades, playas y restaurantes para una estancia de 7 días en Menorca. Presenta dos playas importantes, Cala Presili y Cala Tortuga, y lista las 10 mejores actividades deportivas, que incluyen snorkel, buceo, flyboard y parapente. Además, identifica dos lugares para ver puestas de sol espectaculares, Punta Nati y Caballería, y sugiere comprar quesos, vinos y dulces locales. Finalmente, recomienda dos restaurantes,
Change management by neurological aspects of organizational behaviourIAEME Publication
This document summarizes a research study on how neurological aspects impact organizational behavior and change management. The study examined how changes can influence employee performance, decision-making, teamwork, creativity and engagement. It surveyed 40 small and medium enterprises to understand their perspective on neurology and behavior correlations. The study aims to formulate effective change management policies considering probable deviations in behavior caused by neurological stimuli. Key findings suggest training and experience can improve ethical sensitivity, which influences behavior through neurological aspects. Engaged employees show higher cognitive function, social skills and self-regulation through certain brain networks. High-performing workplaces consider elements like job design and leadership that motivate commitment and focus on results.
Marketing strategy for profit maximization and increase in market shareIAEME Publication
This document summarizes a case study analyzing the marketing strategy of a toothbrush producing company in India. The company saw a drop in profits from the first to second quarter of 2013. The authors analyzed cost and revenue data to determine the reason for the drop was a decrease in sales. They then proposed two strategies to increase profits and market share: 1) Lower prices by 4% to increase sales by 20% or 2) Lower prices by 3.04% to reach the breakeven point and gain market share without risking price competition. Both strategies were shown to increase profits over the first quarter. Additionally, a new tongue cleaner product was proposed to enter new market segments using Ansoff's matrix and a Five Forces analysis to
Imagine 2014: The Devil is in the Details How to Optimize Magento Hosting to ...George White
The document discusses optimizing Magento hosting to increase online sales. It describes a case study of a travel website that experienced a catastrophic event due to a locked database from high query volumes. The root cause was identified and a solution was implemented using a "McManus Magic Shield" to block cache rebuilds if one was already in progress. Load testing results showed that code quality and site configuration are major factors in Magento performance. Best practices for development like reducing requests and using caching can significantly improve scalability. Faster page loading directly correlates to increased conversion rates.
Sequence diagram menggambarkan interaksi antar objek dalam sistem berupa pesan yang ditunjukkan terhadap waktu, dimulai dari trigger aktivitas, proses internal, dan output. Diagram ini terkait dengan use case diagram untuk menunjukkan tahapan dalam suatu use case. Contoh diagram menggambarkan proses penggajian dan pendaftaran pelanggan PLN.
A study on passenger’s satisfaction towards railway services in erode junctionIAEME Publication
This document summarizes a research study on passenger satisfaction with railway services in Erode Junction, India. The key points are:
1. The study used a survey method to assess passenger satisfaction across 7 railway services on factors like tangibles, empathy, assurance, comfort, frequency, reliability, and speed.
2. The results found that 83.8% of passengers were dissatisfied with services, with comfort ranked as the most important service and reliability as the least important.
3. Recommendations to improve passenger awareness included better signage about services, regular announcements, and printing service details on tickets.
Este documento presenta un libro de matemáticas para cuarto grado que incluye ejercicios de cálculo mental, números romanos y conversiones de unidades de medida. El libro contiene preguntas de opción múltiple sobre sumas, restas, multiplicaciones y conversiones de unidades, con instrucciones para que los estudiantes resuelvan los problemas mentalmente.
Az előadás a Tanárszakos hallgatók projektbemutatói - Intel® Teach Essentials a felsőoktatásban c. szekcióban hangzott el. Bajnai Edina a Debreceni Egyetem tanárszakos hallgatója. Projektportfóliójáról több olvasható ebben a cikkben: http://hirmagazin.sulinet.hu/hu/pedagogia/projektportfolio-gondolatolvasas-gesztusokbol-kepekbol, illetve a portfólió teljes egészében megtekinthető a Sulinet.hu-n a Kontextus csoport dokumentumtárában. (A dokumentumok megtekintéséhez az oldalon való regisztráció és a csoportba való belépés szükséges.)
O documento fornece informações sobre o contexto histórico e geográfico no qual Saulo nasceu e cresceu. Resume a história da Cilícia e de Tarso, descreve a estrutura política do Império Romano na época e a situação das províncias sob domínio romano. Também discute a diáspora judaica e o trabalho das entidades espirituais para promover a fraternidade entre os povos do Império.
Economic indicators and stock market performance an empirical case of indiaIAEME Publication
This document summarizes a study that examines the relationship between various economic indicators and stock market performance in India from 1998 to 2014. It finds that GDP growth, gross domestic savings, and gross capital formation have a positive influence on the BSE Sensex, while inflation, exchange rates, interest rates, unemployment, and FDI do not. A regression model is developed that explains 77.2% of the variability in stock market performance based on these economic factors. The study thus provides evidence that certain macroeconomic variables influence long-term stock prices in the Indian market.
Employee mentoring a training and development technique in enhancing organiz...IAEME Publication
This document summarizes an article from the International Journal of Management about employee mentoring. It discusses mentoring as a training and development technique to enhance organizational effectiveness and efficiency. The document provides an overview of mentoring and examines its benefits to both mentees and mentors. It also explores several theories of mentoring and provides conceptual clarifications of mentoring. The key findings are that mentoring can improve both individual and organizational effectiveness, and that it benefits the mentee, mentor and organization.
This document describes the development of a groundwater elevation surface and scoring system for sanitary sewer pipes in Mecklenburg County, North Carolina. The author modeled several potential groundwater elevation rasters using different datasets and methods, including using an existing USGS raster, replicating the USGS methodology with new local data, inverse distance weighted interpolation of local well and stream data, and regression analysis of local elevation, slope, and groundwater data. Pipes were then scored based on their material, the volume of sewage carried, and their position relative to the selected groundwater elevation raster. The scores identified pipes at risk of sewage exfiltration or groundwater infiltration to prioritize rehabilitation efforts.
Review of Groundwater Surfacewater Interaction Modelling Sofware Approaches ...eWater
This report presents the outcomes of a review of the available approaches for modelling groundwater–surfacewater interactions at various spatial and temporal scales with different levels of complexity. It is aimed at determining the deficiencies of the current water modelling approaches for Australian conditions and making recommendations for future model development.
This document is a thesis submitted by David Bautista Gonzalez to Imperial College London in partial fulfillment of an MSc degree. The thesis presents a new closed-form expression for wave speeds predicted by Biot's poroelasticity model. It derives these expressions from first principles for isotropic rock systems and studies the impact of rock and fluid parameters. It also validates the model with experimental data from water-saturated sandstones. Finally, it investigates the relationship between Biot's slow wave and the pressure diffusion equation used in well testing, finding an inconclusive connection that could explain underestimates of rock compressibility.
It is a Thesis of B.Sc Civil by Suman Jyoti
info.sumn.ce@gmail.com
Dhaka University of Engineering and Technology, Gazipur
Thesis of numerical simulation of flow through open channel with series of Groins
This document provides an overview of rating curves, which relate water stage to discharge in open channels. It discusses the measurement of stage and discharge, different types of rating curves, factors that affect rating curves, and extrapolation techniques. The key points are:
1. Stage is measured using staff gauges, sensors, or other devices, while discharge is typically measured using current meters, weirs, flumes or other hydraulic structures.
2. Rating curves can be developed for steady, uniform flow or non-steady, non-uniform flow. Factors like vegetation growth, sedimentation, and variable backwater can impact the curve.
3. Extrapolation is often needed to estimate peak or low discharges beyond
This project report summarizes the design of a road side drainage system for a road in Kenya. It includes an introduction describing the need for efficient road drainage. The objectives are to determine runoff, design drainage channels, and create an efficient and economic drainage system. The literature review covers types of drainage including surface, subsurface and cross drainage. Factors in drainage design like hydrological analysis and hydraulic design using formulas are also summarized.
The document describes research activities conducted by Cristian Gonzalo Guerrero Córdova at the Istituto di Ricerca per la Protezione Idrogeologica (IRPI) in Perugia, Italy from January to July 2015. The objectives were to implement a rainfall-runoff model on the San Antonio River catchment to predict floods using soil moisture data from satellites, rainfall data, and discharge measurements. Models were selected and input data was collected and analyzed. The SCRRM and MISDc rainfall-runoff models were executed for events in 2007 and 2011-2013. Results were analyzed to evaluate the models' ability to forecast floods in the catchment using different data sources.
This document presents the results of modeling studies that evaluated the performance of subsurface drainage systems to lower the water table for on-site wastewater treatment systems (OSWTS) in Ohio. The study analyzed 66 soil series using the DRAINMOD model to simulate daily water table depths under different drain depths and spacings over 30 years. Key outputs included the number of days per year the water table was within certain depths of the surface and probability of exceedance estimates for the water table to reach certain levels. The results provide guidance on drain system design and performance to support OSWTS.
This document proposes improving asset management techniques for underground sewer utilities. Currently, most municipalities assess pipe condition using calendar age or CCTV inspection with the PACP grading system. However, these methods do not consider environmental factors that affect pipe deterioration. The document recommends further studying how environmental conditions like soil type, depth, and traffic impact deterioration rates. An "environmental modification factor" could then adjust PACP grades to more accurately predict rehabilitation needs. Improving assessments would help municipalities efficiently invest their constrained budgets into rehabilitation at the optimal time.
The study aims to better understand formation invasion around wellbores. During drilling, mud filtrate invades the formation, displacing native fluids and altering properties in the invaded zone. This zone is often assumed cylindrical but its true shape is unknown, especially in horizontal wells where density differences can cause gravity segregation. The goals are to use ground penetrating radar (GPR) to image invasion geometries in a physical model and provide data to develop mathematical models. Comparisons of visual observations, GPR images, and numerical simulations show promise for characterizing invasion and correcting borehole measurements.
The document is a stormwater management plan for Pleasant Grove, AL that was submitted after an F4 tornado in 2011 destroyed much of the city's infrastructure. It analyzes the pre- and post-tornado conditions using the WinSLAMM modeling program. The plan proposes cleaning debris, adding vegetation, and installing bioswales and additional catch basins to repair the damaged system and handle stormwater more effectively while improving water quality. Cost estimates are provided for low- and high-cost repair options.
This document discusses techniques for meeting stormwater quality requirements for land development using site design approaches outlined in BASMAA's Start at the Source manual. It describes current regulatory requirements for stormwater treatment, then outlines three site design philosophies - zero discharge areas, self-treating areas, and runoff reduction areas - that can help reduce the amount of runoff requiring treatment. Specific techniques like permeable pavements, concave medians, infiltration areas and green roofs are presented that implement these philosophies. An example compares conventional residential tract design to a design incorporating a 2-acre zero discharge area to demonstrate reduced treatment requirements.
This dissertation submitted by Alejandro Marín Tamayo investigates the dynamic behavior of shallow water pipelines due to seabed liquefaction through numerical modeling. The study assesses how pipelines of varying diameters respond under different water depths when segments of the seabed liquefy and lose their ability to support the pipeline. The analysis considers wave-induced stresses on the seabed both with and without accounting for the dynamic response of the liquefied seabed. The results show that the structural behavior of lighter pipelines is more sensitive to the dynamic seabed response, whereas heavier pipelines are governed more by their own structural behavior when the seabed liquefies.
This document analyzes water quality at three streams in Haliburton Forest where road crossings are present. Benthic invertebrate communities and chemical parameters were used to assess water quality at two study sites - K-1 and W-2. Results from biological indices showed no indication of impairment between reference and exposure units at both sites, suggesting the road crossings did not negatively impact water quality. While additional research is needed, this study provides initial evidence that organic pollution from rural developments may not significantly impact these streams.
This document discusses wind farm design and optimization. It begins with an introduction to wakes, which are velocity deficits created by wind turbines that extract kinetic energy from the air. Wake effects result in energy losses within wind farms. The document then covers wake models, including engineering models and more advanced 3D models used in the industry. It also discusses wake effects within wind farms, including increased turbulence and reduced velocity. The document concludes by mentioning optimization techniques used to minimize wake losses, such as wind farm layout optimization and active wake control methods like pitch control and yaw misalignment. Overall, the document provides an overview of wakes and wake modeling, and how understanding wakes can help optimize wind farm design.
This thesis examines the influence of irrigation water use efficiencies on the sustainability of irrigation at the global scale. The student developed a global hydrological model, PCR-GLOBWB, to simulate irrigation water requirements and consumption under different climate change scenarios from 1960-2099. The model was forced with output from several general circulation models to account for climate uncertainty. Results showed irrigation requirements generally increasing over time, with significant regional variations, highlighting the need to improve irrigation efficiencies to ensure sustainable water resources for agriculture worldwide.
This document provides details about a redevelopment programme for flood management in Singapore following heavy floods in 2010. It includes an introduction describing the floods and complexity of the scenario. The objectives are to redevelop Singapore's outdated drainage system through a wide scope of drainage solutions observed by relevant authorities. The 22-page document then outlines the programme structure and contributions, organizational structure, cost and schedule management, quality planning, and concludes with references.
Hydrological Calibration in the Mount Lofty Ranges using Source Paramenter Es...eWater
This document describes the calibration of a hydrological model of the Mount Lofty Ranges in South Australia using the Parameter ESTimation (PEST) tool. The model was updated with new streamflow data and calibrated using PEST to improve upon a previous calibration that used the Rainfall Runoff Library. PEST optimized hydrological parameters to minimize differences between observed and modeled monthly and daily streamflow and flow durations. The PEST calibration resulted in improved matches to observed streamflow compared to the previous calibration.
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1) The study evaluates the impacts of implementing low impact development (LID) techniques on peak discharge and runoff volume in an urban watershed in Washington D.C. using the Storm Water Management Model.
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3) The results found that LIDs can significantly reduce runoff volume by over 30% but have a negligible impact on peak discharge reduction. Integrating LIDs provides both environmental and economic benefits through reduced flooding and infrastructure costs.
1.
Modeling Stormwater Infiltration in Roadside Swales
Anthony Vecchi
Submitted under the supervision of Dr. John Gulliver to the University Honors Program at the
University of Minnesota-Twin Cities in partial fulfillment of the requirements for the degree of
Bachelor Science, Summa Cum Laude in Civil Engineering.
4/30/2015
3.
Abstract
Swales are stormwater best management practices used to carry stormwater runoff from roads
into the stormwater sewer system. Recent research suggests that swales may serve not only as
stormwater conveyance devices, but also as infiltration devices. Past research by Deletic (2001)
shows that models can be created to estimate the infiltration capacity of swales by assuming that
runoff flows off the road and down the side slope of the swale as a sheet flow. This thesis
investigates how the sheet flow assumption may be avoided by creating a model that routes flow
over a fraction of the side slope using a parameter referred to as ‘fractionally wetted area’. This
model has been developed using Matlab software and is formulated using a numerical solution of
the Green-Ampt infiltration along with numerical solutions of the overland flow. The results of
this model have been compared to three model studies and a field experiment. The comparison
showed that the accuracy of the model is limited by the accuracy of the inputs relating to the soil
parameters of the swale.
4.
Table of Contents
1
Introduction
.......................................................................................................................................
1
1.1
Review
........................................................................................................................................................
2
2
Model Development
.........................................................................................................................
4
2.1
Model Equations
......................................................................................................................................
5
2.2
Model Structure
.......................................................................................................................................
7
3
Physical Experiments
....................................................................................................................
11
4
Results
..............................................................................................................................................
14
5
Conclusions
.....................................................................................................................................
19
6
References
.......................................................................................................................................
20
Appendix
A
.........................................................................................................................................
A-‐1
6.2
Model Trial Inputs
..............................................................................................................................
A-‐1
6.3
Matlab Model
.......................................................................................................................................
A-‐2
5.
Table of Tables
Table 1 : Model Input Parameters
......................................................................................................
9
Table 2 : Flume Model Study Results
..............................................................................................
12
Table 3 : Selected Field Experiment Results
..................................................................................
13
Table 4 : Model Results
......................................................................................................................
14
Table 5 : Revised Model Results using adjusted ks
......................................................................
17
Table A1 : Trial 1
...............................................................................................................................
A-‐1
Table A2 : Trial 2
...............................................................................................................................
A-‐1
Table A3 : Trial 3
...............................................................................................................................
A-‐1
Table A4 : Field Experiment Trial
.................................................................................................
A-‐2
Table of Figures
Figure
1 : Flume Model Study
..........................................................................................................
12
Figure
2 : Field Experiments at Hwy 51
........................................................................................
13
Figure
3 : Modeled specific discharge at the bottom of the side slope for Trial 1
................
15
Figure
4 : Modeled specific discharge at the bottom of the side slope for Trail 2
................
15
Figure
5 : Modeled specific discharge at the bottom of the side slope for Trial 3
................
16
Figure
6 : Modeled specific discharge at the bottom of the side slope for the Field
Experiment
............................................................................................................................................
16
Figure
7 : Modeled specific discharge at the bottom of the side slope for Trial 1 with ks
changed from the estimated 12.83 cm/hr to 8 cm/hr
....................................................................
17
Figure
8 : Modeled specific discharge at the bottom of the side slope for Trial 2 with ks
changed from the estimated 12.83 cm/hr to 8 cm/hr
....................................................................
18
Figure
9 : Modeled specific discharge at the bottom of the side slope for Trial 3 with ks
changed from the estimated 12.83 cm/hr to 8 cm/hr
....................................................................
18
6. Vecchi 1
1 Introduction
The Pollution Prevention program led by the Minnesota Pollution Control Agency (MPCA) has
the goal of reducing nutrient loading on Minnesota’s lakes and rivers, thereby reducing future
costs associated with pollution. The MPCA’s Minnesota Stormwater Manual lays out several
devices, called stormwater Best Management Practices (BMPs), which can be used for
stormwater volume reduction and/or nutrient removal (MPCA, 2014). Documentation for each
BMP includes design guidelines and estimated performance in terms of volume reduction, total
suspended solids (TSS) removal, total phosphorous (TP) removal, and total nitrogen (TN)
removal. The MPCA may award pollution prevention credits to parties that successfully
implement and maintain a BMP. The extent of these credits is dependent on the type of BMP
chosen and its corresponding removal/reduction estimates.
Swales are grassed (or otherwise vegetated) channels used as a stormwater BMP to capture
stormwater runoff and route it elsewhere, typically to a storm sewer. A swale’s primary
stormwater treatment capability is in filtering solids from the flow as it passes over the grass in
the channel. The infiltration capacity of swales is acknowledged in the MPCA’s Stormwater
Manual, but there is no effort to quantify the expected volume reduction due to infiltration as
stormwater runs off a road and into the center of a swale. For this reason, owners of swales,
including the Minnesota Department of Transportation, may not be getting enough pollution
prevention credits for the infiltration taking place in their swales.
7. Vecchi 2
The properties of a swale that affect its infiltration capacity are complex and carry with them
substantial uncertainty. These properties include initial soil moisture content, saturated hydraulic
conductivity, effective wetting front suction, and fraction wetted (a parameter to be introduced
later in this paper). Due to this reality, translating the physical conditions into a mathematical
model can be challenging. This has led to the MPCA relying on the Minimal Impact Design
Standards (MIDS) Calculator, an empirical tool, to estimate infiltration in swales. The goal of
this thesis is to model stormwater infiltration as runoff flows down the side slope of a swale
without assuming that the runoff will flow as a sheet.
1.1 Review
Other studies have approached the problem of infiltration in grassed swales using more rigorous
methods. A study by Deletic (2001) dealt most directly with sediment transport, but dealt with
infiltration mathematically. In this study, Deletic used the Green-Ampt method to estimate
infiltration, the kinematic wave equation to model overland flow, and incorporated the effects
that sediment deposition could have on the terrain of the swale slope. The model was created
using TRAVA and was calibrated against known sedimentation behavior. The model results
represent a hypothetical swale’s behavior and were not compared to physical results. The model
also assumes that runoff travels down the slope as a sheet flow.
Deletic and Fletcher (2005) conducted a field and modeling study regarding stormwater flow
down the center of a swale. The focus of this study was suspended sediment removal, but the
8. Vecchi 3
TRAVA model employed did account for infiltration. This model was able to accurately estimate
swale outflow, but only after measured results were used to calibrate the infiltration parameter
saturated hydraulic conductivity (ks). In other words, stormwater volume reduction could only be
estimated for a swale if extensive field studies were done to determine its infiltration
performance. As before, this model is based on the assumption that runoff flows down the
swale’s side slope as a sheet.
The goal of this study is to develop a simple and accurate model to predict the volume reduction
of stormwater traveling down the side slope of a swale during a certain storm based on physical,
measurable swale parameters. This model will consider the fact the runoff down a slope will not
occur as a sheet flow, but will only pass over a fraction of the slope area. This fact manifests
itself in the form of the ‘fractionally wetted area’ parameter. Generally, the model presented in
the following section may be implemented to develop improvements in relations used in the
MIDS Calculator to determine volume reduction and to make decisions regarding pollution
prevention credits.
9. Vecchi 4
2 Model Development
The model simulates stormwater runoff flowing off of a paved road and down the slope of a
swale into its channel. The model relies on the assumption that there is no standing water on the
slope of the swale prior to the beginning of the rain event. This is an acceptable assumption
because the relatively steep slope inhibits the accumulation of water. The output of the model is
the runoff at the bottom of the slope over the duration of the storm as well as the volume of rain,
volume of runoff, and percent volume reduction during the storm. It should be noted that the
accuracy of the outputs is limited most directly by the accuracy of the input soil parameters
(most notably ks). Other errors incurred by the model include those associated with an iterative
solving method. However, this error tends to be on the order of 1% of the volume of rain.
The model solves for infiltration using the Green-Ampt assumptions, the Manning’s Equation,
and a simple mass balance in each cell moving down the slope at discretized time steps
throughout the duration of the storm. The key to differentiating this model from others (Deletic
2001, 2005) is the use of a fractionally wetted area in mass balance and infiltration computations.
Fractionally wetted area (fw) refers to the percent of slope area passed over by runoff due to the
natural, small-scale terrain of the slope’s surface. Natural rills and surface depressions mean that
the assumption that runoff will flow over the slope as a sheet flow is inappropriate and could
lead to an over-estimation of the amount of infiltrated runoff.
10. Vecchi 5
2.1 Model Equations
The first step in the model is to discretize the slope into cells in the direction of the slope. The
model includes a routine to select an optimized time-step that reduces model computation errors
by ensuring that the Courant number does not exceed 1. The computations of the model begin by
computing runoff from the contributing road surface. The cell index is given by k, qin represents
the specific discharge into the top of the cell, ir represents the rainfall intensity over the road, i
represents the rainfall intensity over the swale, w represents the contributing width in the
direction parallel to the swale slope of the road, Δy represents the length of the cells in the
direction parallel to the swale slope, and fw is the fractionally wetted area for the cell. The
effective rainfall intensity (ie) may be computed as shown below.
𝑖!,! =
!!",!
∆!
+ 𝑖 (1)
For infiltration calculations, ie will be used to estimate the flow entering the top of each cell in
each time step that may be infiltrated. In other words, the maximum infiltration rate is limited by
ie instead of i. Following the method for ponding during an unsteady rain, the ponding time is
computed for each cell as soon as water reaches that cell (Chu, 1978). The current time, relative
to the ponding time, determines the infiltration rate.
𝑡! =
!!!!!
!!,!!!!
!!!!!,!!!!!!,!
!!,!
+ 𝑗 − 1 ∆𝑡 (2)
𝑓! = 𝑖!,! 𝑖𝑓 𝑗!"#$",! − 𝑗 Δ𝑡 ≤ 𝑡! (3)
𝑓! = 𝑘!
!!!
!!!!,!
+ 1 𝑖𝑓 𝑗!"#$",! − 𝑗 Δ𝑡 > 𝑡! (4)
𝐹!,! = 𝐹!!!,! + 𝑓!,!∆𝑡𝑓!,! (5)
11. Vecchi 6
In these equations, tp is the time of ponding, ks is the saturated hydraulic conductivity, ψ is the
initial effective wetting front suction head, Δθ is the change in moisture content, P is the
cumulative rainfall for a certain cell (in terms of effective intensity), R is the cumulative runoff
for a certain cell, f is the Green-Ampt infiltration rate, F is the cumulative infiltration, j is the
time step index, jstart is the time index at which water enters a certain cell, and Δt is the time step.
The infiltration is converted into an equivalent specific discharge, qinf into the soil with the
relation:
𝑞!"#,! = 𝑓!∆𝑦 (6)
Next, a mass balance is used to determine the flux of water in each cell at each time step. As
mentioned earlier, this mass balance assumes that all water enters the top of the cell. This is a
reasonable assumption due to the relatively small size of the cells.
𝑂𝑢𝑡𝑓𝑙𝑜𝑤 = 𝐼𝑛𝑓𝑙𝑜𝑤 − 𝐼𝑛𝑓𝑖𝑙𝑡𝑟𝑎𝑡𝑖𝑜𝑛 −
𝑑𝑉
𝑑𝑡
(7)
or
𝑞!"#,! = 𝑞!",! − 𝑞!"#,! + 𝑖∆𝑦 −
∆!!,!∆!
∆!
(8)
where V is volume of water on the soil surface in the cell and qout is the specific discharge from
the cell. In this equation, Δh represents the change in depth of runoff in that cell during that time
step. The current depth of runoff in a cell during a certain time step is given by rearranging
Manning’s equation in the following manner:
ℎ!,! =
!!!"#,!
!.!
!!.!
(9)
12. Vecchi 7
where S represents the side slope of the swale and n is Manning’s roughness coefficient. The
Manning’s n value is selected based on the vegetation lining the swale. Next, the change in depth,
Δhj,k, can be computed in the following manner.
∆ℎ!,! = ℎ!,! − ℎ!!!,! (10)
Finally, the Courant, Cou, number may be computed for each cell at each time step using the
following equation.
𝐶𝑜𝑢!,! =
!!"#,!
!!,!
∆!
∆!
(11)
The relationship between the outflow of a cell and the inflow of the cell below it is related to the
fractionally wetted area in the following manner.
𝑄!"#,! = 𝑞!"#,!∆𝑥𝑓!,! (12)
𝑞!",! =
!!"#,!!!
∆!!!,!
(13)
Where Δx represents the length of the modeled swale in the direction of the contributing road.
2.2 Model Structure
The model is constructed in a linear way using Matlab software, evaluating each cell
successively for each time step. Initially, the model includes routines that convert all inputs into
the base SI units for further calculations. The body of the model follows the following
progression, outlined by the list shown below.
Begin loop through time (index: j)
Begin loop through space (index: k)
13. Vecchi 8
• Evaluate equation (1) if k=1, equation (13) if k>1
• Evaluate equation (2)
• Evaluate equation (3)
• Evaluate equation (4) or (5)
• Evaluate equation (6)
• Evaluate equation (7)
• Iteratively solve:
o Equations (8), (9), and (10)
• Evaluate equation (11)
• Evaluate equation (12)
End loop through space (index: k)
End loop through time (index: j)
The iterative solution for qout, h, and Δh can incur error into the final result. This effect is
mitigated by imposing an iterative tolerance on Δh of 0.0000005 m. Methods are implemented
into the model to improve convergence of this iterative process by improving the guesses for Δh.
The effectiveness of this iteration is related to the Courant number. Lower Courant number
results in the need for more iterations, and often larger errors. Similarly, results of the model
with Courant numbers >1 are suspicious, as this implies that flow is traveling over multiple cells
in a single time step. A routine has been installed into the model to select a time step that results
in the maximum Courant number falling between 0.9 and 1. Ultimately, this leads to a more
robust model because the user need not worry about selecting a valid time step.
14. Vecchi 9
Lastly, the model creates a plot of discharge at the bottom of the slope over the duration of the
storm. This helps the user visualize when flow will begin to appear into the swale’s channel, and
the steady state discharge into this channel. The model also reports the total inflow being
imposed on the swale and total volume of runoff. Errors in the model (due to the iterative
solution) are determined by subtracting the total outflow volume during the storm from the total
inflow volume.
The model requires several inputs that represent physical, measurable quantities, given in Table
1.
Table 1: Model Input Parameters
Parameter Unit
Rainfall intensity over road (ir) in/hr
Rainfall intensity over swale (i) in/hr
Length of slope (L) m
Number of cells down slope -
Duration of storm event hr
Effective wetting front suction (ψ) cm
Change in soil moisture (Δθ) -
Saturated Hydraulic Conductivity (ks) cm/hr
Length of road in direction of slope (w) m
15. Vecchi 10
Width of swale (Δx) m
Fraction wetted (fw) -
Side slope (S) -
Manning’s n (n) -
16. Vecchi 11
3 Physical Experiments
A set of laboratory and field experiments was conducted by Ms. Maria Garcia-Serrana at the
University of MN, working under the direction of Dr. John Gulliver and Dr. John Nieber. Ms.
Garcia-Serrana conducted this study to determine how fractional coverage of flow down the side
slope of a swale affects its capacity to infiltrate (Garcia-Serrana, 2015). The study included 3
trials using a full-scale model built at the St. Anthony Falls Laboratory and field experiments
using swales across the Twin Cities Metro area.
For the model study, a full-scale 1:6 slope was built using compacted loamy sand. For each trial,
water was added to the top of the slope for 60 minutes at a rate equivalent to a 2.5 cm/hr rain
event. Data collected from each trial includes volume of water infiltrated (measured using
drainage pipes installed below the soil), volume of runoff, micro-topography of the surface, and
wetted surface area. For the first trial, the slope was smoothed with a trowel before testing. For
the second trial, 3 semi-circular incisions were made along the length of the slope using a 1.8”
diameter pipe (Figure 1). The third trial had 5 semi-circular incisions of the same style. The
results of the model study can be found in Table 2.
17. Vecchi 12
Figure
1: Flume Model Study
Table 2: Flume Model Study Results
Trial # of Rills Input Water Volume (L) Runoff Volume (L)
1 0 234 123.3
2 3 234 157.5
3 5 234 164.5
The field experiments included 4 trials at swale locations across the Twin Cities area (Hwys 13,
47, 55, and 77). An example illustration is given in Figure 2. For each trial, the surface
vegetation was trimmed and the surface roughness was measured using a pin meter. A discharge
equivalent to a 5.6 cm/hr rain event was applied at the top of the swale for 30 minutes for each
18. Vecchi 13
trial. For this study the total runoff volume, micro-topography of the swale, the intensity of
runoff, and the wetted surface area over time were measured. For this report, only the results of 1
of the field trials will be considered. The results of this trial can be found in Table 3.
Figure
2: Field Experiments at Hwy 51
Table 3: Selected Field Experiment Results
Trial Input Water Volume (L) Runoff Volume (L)
1 255.4 89.9
19. Vecchi 14
4 Results
The Matlab model was run using inputs to simulate each of the 3 flume model trials and the
selected field experimental trial. The input parameters used in the model were taken directly
from the results of the physical measurements made on the compacted laboratory soil. These
inputs, for each model run, may be found in the appendix. The model results shown in Table 4
and Figure 3, Figure 4, Figure 5 and Figure 6 compare modeled runoff volumes with the
measured runoff volumes, as well as show the runoff intensity (as a specific discharge) over the
course of the simulated storm. A second set of model trials for the flume study using a lower ks
value (8 cm/hr instead of the measured 12.83 cm/hr) is given in Table 5 and Figure 7, Figure 8,
and Figure 9 to demonstrate the affect that the saturated hydraulic conductivity has on the model
results and to consider an alternative estimate to the ks value.
Table 4: Model Results
Trial
Input Water Volume
(L)
Runoff Volume
(L)
Model Runoff Volume
(L)
Model Mass Balance
Error (L)
1 234 123.3 65.5 0.3
2 234 157.5 91.3 1.8
3 234 164.5 106.5 0.2
Field 255.4 89.9 177.6 0.4
20. Vecchi 15
Figure
3: Modeled specific discharge at the bottom of the side slope for Trial 1
Figure
4: Modeled specific discharge at the bottom of the side slope for Trail 2
21. Vecchi 16
Figure
5: Modeled specific discharge at the bottom of the side slope for Trial 3
Figure
6: Modeled specific discharge at the bottom of the side slope for the Field Experiment
22. Vecchi 17
Table 5: Revised Model Results using adjusted ks
Trial
Input Water Volume
(L)
Runoff Volume
(L)
Model Runoff Volume
(L)
Model Mass Balance
Error (L)
1 234 123.3 121.1 0.3
2 234 157.5 138.4 1.2
3 234 164.5 148.1 0.2
Figure
7: Modeled specific discharge at the bottom of the side slope for Trial 1 with ks changed from
the estimated 12.83 cm/hr to 8 cm/hr
23. Vecchi 18
Figure
8: Modeled specific discharge at the bottom of the side slope for Trial 2 with ks changed from
the estimated 12.83 cm/hr to 8 cm/hr
Figure
9: Modeled specific discharge at the bottom of the side slope for Trial 3 with ks changed from
the estimated 12.83 cm/hr to 8 cm/hr
24. Vecchi 19
5 Conclusions
The goal of the Matlab model is to predict runoff, for a given storm, along the side slope of a
swale with overland flow that covers a fraction of the slope surface. The model developed has
proven to be robust and computationally accurate. The results of the model analysis show,
however, that the validity of the model’s ability to predict infiltration and runoff depends on the
accuracy of the model’s inputs. For example, this study also indicates that the model was
sensitive to infiltration parameters such as ks.
The fraction wetted parameter also has uncertainty associated with it. Flume studies at Saint
Anthony Falls Laboratory indicate that the fw parameter may vary both in space and time over
the course of a storm. This effect was not measured in the study, and was therefore not included
in the model. In reality, the runoff may flow closer to a sheet during the early stages of a storm
before developing rills and reaching a steady state fraction of coverage.
Future research may be undertaken to develop greater accuracy in estimating physical parameters
such as ks and fw. The model trials show that manipulating inputs such as these can yield model
results that closely simulate the behavior observed in physical experiments. Eventually, this
method may be employed to estimate volume reduction in swales during a given storm. This
would allow agencies such as the MPCA to better distribute Pollution Prevent credits and to use
a version of this model to establish infiltration rates for various swales in the MIDS Calculator.
25. Vecchi 20
6 References
Chu,
S.
T.
(1978).
Infiltration
During
an
Unsteady
Rain.
Water
Resources
Research
,
14
(3),
461-‐466.
Deletic,
A.
(2001).
Modelling
of
water
and
sediment
transport
over
grassed
areas.
Journal
of
Hydrology
(248),
168-‐182.
Deletic,
A.,
&
Fletcher,
T.
D.
(2005).
Performance
of
grass
filters
used
for
stormwater
treatment
-‐
a
field
and
modelling
study.
Journal
of
Hydrology
(317),
261-‐275.
Garcia-‐Serrana,
M.
(2015,
March).
Infiltration
into
Roadside
Drainage
Ditches.
UPDATES
,
10.2
.
Minneapolis,
Minnesota,
United
States
of
America.
MPCA.
(2014).
Minnesota
Stormwater
Manual.
Retrieved
March
28,
2015,
from
Minnesota
Stormwater
Manual
Wiki:
http://stormwater.pca.state.mn.us/index.php/
27. Vecchi A-‐2
Table A4: Field Experiment Trial
6.3 Matlab Model
Time step selection routine
T=10000; % Number of time steps
max_Cou=slope_runoff( ir,i,length,rows,duration,T,psi,deltheta,ks,w,x,fw,S,n
);
while max_Cou>1 || max_Cou<0.9
T=round(T*max_Cou);
max_Cou=slope_runoff( ir,i,length,rows,duration,T,psi,deltheta,ks,w,x,fw,S,n
);
end
Green-Ampt Infiltration routine
function [ f ] = Green_Ampt_rate( psi,deltheta,ks,ie,tstep,F,j,jstart,P,R )
X=psi*deltheta;
tp=(((ks*X/(ie-ks))-P+R)/ie)+(j-1-jstart)*tstep;
if tp>(j-jstart)*tstep
f=ie;
else
if (j-jstart)==0
f=ie;
else
f=ks*(X/F+1);
end
end
if f>ie
f=ie;
end
end
Runoff routine
function [ max_Cou ] = slope_runoff(
28. Vecchi A-‐3
ir,i,length,rows,duration,T,psi,deltheta,ks,w,x,fw,S,n )
%% Unit conversions
ir=ir*2.54/360000; % Converts to m/s
i=i*2.54/360000; % Converts to m/s
dy=length/rows;
duration=duration*3600; % Converts to s
tstep=duration/T;
psi=psi/100; % Converts to m
ks=ks/360000; % Converts to m/s
%% Setting up variables
qin=zeros(rows,1);
qinf=zeros(rows,1);
qout=zeros(rows,1);
Qout=zeros(rows,1);
ie=zeros(rows,1);
dh=zeros(rows,1);
f=zeros(rows,1);
F=zeros(T,rows);
h=zeros(T,rows);
track_depth=zeros(T,rows);
Cou=zeros(T,rows);
inf=zeros(T,1);
qslope=zeros(T,1);
dh_guess=zeros(10,1);
qout_it=zeros(10,1);
diff_it=zeros(10,1);
P=zeros(rows,1);
R=zeros(rows,1);
jstart=zeros(rows,1);
%% Calculations for flow down slope during storm
for j=1:T % Iteration through time
for k=1:rows % Iteration through space
if k==1
qin(k)=ir*w/fw(k); % Inflow from road
else
qin(k)=Qout(k-1)/(x*fw(k)); % Inflow from cell above
end
ie(k)=qin(k)/dy+i; % Effective intensity
if jstart(k)==0
if qin(k)>0
jstart(k)=j;
end
end
if jstart(k)>0
if j==1
f(k)=Green_Ampt_rate(psi,deltheta,ks,ie(k),tstep,0,j,jstart(k),P(k),R(k));
F(j,k)=f(k)*tstep*fw(k);
else
f(k)=Green_Ampt_rate(psi,deltheta,ks,ie(k),tstep,F(j-
1,k),j,jstart(k),P(k),R(k));
F(j,k)=F(j-1,k)+f(k)*tstep*fw(k);
29. Vecchi A-‐4
end
else
f(k)=0;
F(j,k)=0;
end
P(k)=P(k)+ie(k)*tstep;
qinf(k)=f(k)*dy;
% Iterative solution for qout, dh, and h
it=1; % Initialize iteration counter
Tolerance=0.0000005; %Specify iteration tolerance
diff=1; % Initialize variable subjected to tolerance
dhold=0; % Initial guess for dh
while abs(diff)>Tolerance
qout(k)=qin(k)-qinf(k)+i*dy-dhold*dy/tstep;
if qout(k)<0
if it==1
qout(k)=0;
else
qout(k)=qout_it(it-1)/2;
end
end
qout_it(it)=qout(k);
h(j,k)=((n*qout(k))^0.6)/S^0.3;
if j==1
dhnew=h(j,k);
else
dhnew=h(j,k)-h(j-1,k);
end
dh_guess(it)=dhnew;
diff_it(it)=dhnew-dhold;
diff=diff_it(it);
if it>2
m=(diff_it(it-1)-diff_it(it-2))/(dh_guess(it-1)-dh_guess(it-
2));
if abs(m)<0.1
m=0.1*m/abs(m);
end
if abs(m)>10
m=10*m/abs(m);
end
dhold=dh_guess(it-2)-diff_it(it-2)/m;
else
dhold=dhnew;
end
it=it+1;
end
30. Vecchi A-‐5
dh(k)=dhnew;
if j>1
for p=1:rows
track_depth(j,p)=h(j-1,p)+dh(p);
end
end
Cou(j,k)=(qout(k)/h(j,k))*tstep/dy;
Qout(k)=qout(k)*x*fw(k);
R(k)=R(k)+qout(k)*tstep/dy;
end
inf(j)=sum(qinf.*fw*tstep);
qslope(j)=qout(rows);
end
max_Cou=max(max(Cou));
if max_Cou<1 && max_Cou>0.9
%% Mass Balance
jstart
road=ir*w*x*duration;
rain=i*dy*x*sum(fw)*duration;
runoff=sum(qslope)*x*fw(rows)*tstep;
infil=sum(inf)*x;
standing=h(T,:)*fw*dy*x;
Mass_Balance=(road+rain-runoff-infil-standing)*1000;
Volume_Runoff=(standing+runoff)*1000;
Max_iterations=max(size(dh_guess))+1;
fprintf('Minimum Depth = %.5f Ln',min(min(track_depth)));
fprintf('Total Inflow = %.1f Ln',(road+rain)*1000);
fprintf('Runoff = %.1f Ln',Volume_Runoff);
fprintf('Mass Balance Error = %.1f Ln',Mass_Balance);
fprintf('Time steps used = %.fn',T);
fprintf('Maximum of %.f iterations required for solutionn',Max_iterations);
fprintf('Maximum Courant Number of %.4fn',max_Cou);
%% Plot
tt=(tstep/3600):(tstep/3600):(duration/3600);
plot(tt,qslope);
title('Specific Discharge into Swale Channel Over Time');
xlabel('Time (hr)');
ylabel('Specific Discharge (m^{2}/s)');
end
end