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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

Effect of mixed-grass cover and native-soil filter on urban runoff quality

Popkin, Barney P. January 1973 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references.
2

Capturing the essential spatial variability in urban hydrologic miodeling by GIS.

Zhang, Lihong January 1999 (has links) (PDF)
Thesis (M. S. - Renewable Natural Resources)--University of Arizona, 1999. / Includes bibliographical references (leaves 117-120).
3

The water balance of urban impermeable surfaces : catchment and process studies

Davies, Hilary Ann January 1981 (has links)
An examination of research and information needs in urban hydrology suggested the investigation of urban water balances and micro- hydrological processes. This should facilitate more accurate modelling of the rainfall-runoff process from urban impermeable surfaces. Greater London data produced annual water balances for 5 heavily urbanized Thames tributaries and estimates of the annual yield ranging from 12-72%. Mean annual runoff for largely rural basins in South East England in comparison was 15-44% of rainfall. The inadequacy of the data for water balance studies led to the instrumentation of a small urbanized catchment at Redbourn, Hertfordshire. Standard meteorological measures were recorded. New instrumentation was designed to measure runoff from shallow pitched roofs while commercially produced instruments were adapted and installed to monitor runoff from a block of flat asphalt-and-chippings garage roofs, and runoff from asphalt roads and pavements at the highway drain outfall. Runoff from these impermeable surfaces is less than 100% even during winter months when evaporation is low. Percentage runoff is 76% for both the pitched and flat roofs while that from the paved surfaces is only 17%. Despite differences in slope, runoff volumes from the pitched and flat roofs are almost identical suggesting that the flat roof does not afford much greater depression storage and evaporation losses. The flat roof does however attenuate storm runoff producing lower flow rates and longer runoff duration than the pitched roofs. Road runoff is very low because of infiltration. The calculated depression storage is 0.25 mm for both roof types and 1.00 mm for the road surface. An average water balance compiled for the roofs gave evaporation as the residual 19% of rainfall. Using an average roof evaporation rate in the road surface water balance gave infiltration as 36% of rainfall with 17% runoff, 21% evaporation and 26% depression storage. Runoff from metre-square roof samples produced slightly different percentage runoff figures for the same winter period. Average percent runoff from red Redland 49 tiles (set at 30°) was 98%, grey Stonewold tiles (set at 17½°) produced 85% and asphalt roofing felt produced 38% runoff. These results are evaluated in the light of probable errors in measurements.
4

Lotus and the Machine: architecture for the symbiosis of cities and urban hydrology

Du Plessis, Claire January 2015 (has links)
Includes bibliographical references / Despite the abundance of fresh water produced in the mountains surrounding Cape Town, a range of factors contribute towards the imminent water crisis felt locally and internationally. While governing bodies have management strategies and infra structural upgrades planned, these interventions address issues of water quantity only. Steadily declining water quality is an equally important issue which will continue to impact on available fresh water quantities if action is not taken. The threats on water availability in cities stem from growing urbanization itself. The question this dissertation poses is how architecture can encourage a symbiotic relationship between built and natural environments, with special regard for urban water systems. The answer is found in the balance of quantity management, quality improvement and long-term protection of water - a symbiosis between city and urban hydrology. This dissertation documents the research and design of a speculative architectural proposition to embody such a symbiosis. It is hypothesized that the design must address quantity and quality issues simultaneously by coupling infrastructure with community facilities. This will ensure immediate remediation of a water system and encourage a long-lasting protection of water quality through passive education and public conscientizing. The research identifies the Lotus River, located near the Philippi Horticultural Area in Cape Town, as an appropriate representative of the urban hydrological cycle in Cape Town. Through an understanding of the major pollutants in the river and a study of current technology, an industrial process which recycles pollution into fertilizer is proposed as the major programme of the project. This programme is overlaid with an agricultural training center and public amenities which encourage and incentivise environmental awareness among the community. The architectural theories of symbiosis and the social' condenser are proposed as precedent for the way in which architecture has, through the creation of transitional spaces, attempted to usher society into a new way of living. This project explores the creation of a transitional space between building and nature to encourage a symbiotic relationship between urbanity and water, where the Lotus meets the Machine.
5

Virginia Tech Duck Pond Retrofit for Improved Water Quality in Stroubles Creek

Thye, F. Brian 05 February 2003 (has links)
Stroubles Creek is registered on Virginiaâ s 303(d) list of impaired waters for both benthic and fecal coliform impairments. The upper reach of the creekâ s watershed drains into two ponds on the Virginia Tech campus. The area draining to the ponds, approximately 715 acres, encompasses most of the Town of Blacksburg and the Virginia Tech campus. Below the ponds, the creekâ s watershed is primarily forested and agricultural, with some areas of residential development. In order to improve water quality downstream, the two ponds will be converted to a water quality facility by redirecting all flow from the northern branch of Stroubles Creek into the upper, smaller pond, which then flows into the larger pond below. With flow into the upper pond increasing dramatically, the dam between the two ponds and associated overflow structures were evaluated and redesigned to protect the dam from overtopping and possible washout. In addition, concrete weirs were designed and will be constructed on both branches of Stroubles Creek above the ponds for future installation of flow and water quality monitoring equipment. Above the ponds, the banks along both branches of the creek have become severely eroded. Interlocking concrete block armoring was designed for the stream banks to reduce erosion and protect the trees growing along the creek. This project was jointly funded by Virginia Tech and a grant from the Virginia Department of Conservation and Recreation Water Quality Improvement Fund. Construction will be performed by the Capital Design department of Virginia Tech. / Master of Science
6

Modelagem hidráulica/hidrológica do escoamento superficial com a utilização do SWMM integrado ao SIG : o exemplo de Ilha Solteira-SP /

Santini Junior, Mauricio Antonio. January 2018 (has links)
Orientador: Jefferson Nascimento de Oliveira / Resumo: Desde o começo da formação dos conglomerados urbanos no Brasil, a drenagem urbana sempre teve uma abordagem sanitarista. Tal prática causa cada vez mais problemas como enchentes e eutrofização dos corpos d’água. Atualmente, os constantes problemas enfrentados pelas cidades retratam a forte situação de negligência em que se encontra este tema no país. Neste prisma, o presente projeto teve como objetivo propor um modelo Hidráulico/Hidrológico da rede de drenagem de Ilha Solteira, a fim de subsidiar decisões futuras de gestão da bacia urbana como um todo. A área de estudo foi a sub-bacia do córrego Sem Nome localizado na cidade de Ilha Solteira-SP. A base de dados utilizada foi obtida por meio de estudos disponibilizados pela prefeitura, ensaios de campo e a instalação de sondas e pluviógrafos na área de projeto. Além disso, foram usadas imagens de satélite obtidas por meio do Software Livre Google EarthPro. Foram utilizados os softwares ArcGis 10 e o Storm Water Management Model (SWMM) para estabelecer um modelo digital representativo da bacia, por meio das equações de Saint-Venant 1D e da onda cinemática. Foi realizada uma análise de sensibilidade, além da calibração e validação do sistema. Os cálculos desta pesquisa tiveram por base 31 eventos ocorridos durante o desenvolvimento da mesma, e o modelo foi avaliado sob o escopo de cinco indicadores estatísticos. Os resultados mostraram que o modelo elaborado teve desempenho satisfatório, com coeficientes de eficiência de Nash-Su... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Since the beginning of the formation of urban conglomerates in Brazil, the urban drainage has been taken a sanitary approach. This practice has caused more and more problems, such as flooding and eutrophication of streams. The constant problem faced by most cities is the strong neglect that lies in this country. In this perspective, the present work proposes a Hydraulic/hydrological model of the storm water network of Ilha Solteira, in order to support future subsidization of urban basin management as a whole. The study area was the sub-basin of the Sem Nome stream located in the city of Ilha Solteira-SP. The used database was obtained by city hall studies, field trials, probes and rain gauges installed in the project area; the satellite images were obtained by using the Free Software EarthPro., ArcGis 10 and Stormwater Management Model (SWMM), to establish a representative digital model of the basin using the Saint-Venant 1D equations and the kinematic waveform. Sensitivity, calibration and validity analyses of the system were performed, 31 events were captured and a model was evaluated by five statistic indicators. The results have shown that the elaborated model has presented a satisfactory performance with mean Nash-Sutcliffe efficiency coefficients of 0.69, index of agreement of 0,92, average error in peak flow equivalent to 21% and mean error with no peak time equal to 2 minutes and 40 seconds. / Mestre
7

Toward a more complex understanding of urban stream function : assessing post-developmental recovery period and channel morphology and the relationship between urban built form, land cover pattern, and hydrologic flow regime /

Greve, Adrienne I. January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 148-163).
8

Modelagem hidráulica/hidrológica do escoamento superficial com a utilização do SWMM integrado ao SIG: o exemplo de Ilha Solteira-SP / Hydrological modeling of urban surface runoff using the SWMM integrated to GIS: the example of Ilha Solteira-SP

Santini Junior, Mauricio Antonio 06 April 2018 (has links)
Submitted by Mauricio Antonio Santini Júnior (mauriciosantinijr@gmail.com) on 2018-05-15T11:06:40Z No. of bitstreams: 1 SANTINI 2018.pdf: 9794262 bytes, checksum: 605025f85b9ea4ae9bee124b72b6272a (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-05-15T12:32:53Z (GMT) No. of bitstreams: 1 santini junior_ma_me_ilha.pdf: 9794262 bytes, checksum: 605025f85b9ea4ae9bee124b72b6272a (MD5) / Made available in DSpace on 2018-05-15T12:32:53Z (GMT). No. of bitstreams: 1 santini junior_ma_me_ilha.pdf: 9794262 bytes, checksum: 605025f85b9ea4ae9bee124b72b6272a (MD5) Previous issue date: 2018-04-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Desde o começo da formação dos conglomerados urbanos no Brasil, a drenagem urbana sempre teve uma abordagem sanitarista. Tal prática causa cada vez mais problemas como enchentes e eutrofização dos corpos d’água. Atualmente, os constantes problemas enfrentados pelas cidades retratam a forte situação de negligência em que se encontra este tema no país. Neste prisma, o presente projeto teve como objetivo propor um modelo Hidráulico/Hidrológico da rede de drenagem de Ilha Solteira, a fim de subsidiar decisões futuras de gestão da bacia urbana como um todo. A área de estudo foi a sub-bacia do córrego Sem Nome localizado na cidade de Ilha Solteira-SP. A base de dados utilizada foi obtida por meio de estudos disponibilizados pela prefeitura, ensaios de campo e a instalação de sondas e pluviógrafos na área de projeto. Além disso, foram usadas imagens de satélite obtidas por meio do Software Livre Google EarthPro. Foram utilizados os softwares ArcGis 10 e o Storm Water Management Model (SWMM) para estabelecer um modelo digital representativo da bacia, por meio das equações de Saint-Venant 1D e da onda cinemática. Foi realizada uma análise de sensibilidade, além da calibração e validação do sistema. Os cálculos desta pesquisa tiveram por base 31 eventos ocorridos durante o desenvolvimento da mesma, e o modelo foi avaliado sob o escopo de cinco indicadores estatísticos. Os resultados mostraram que o modelo elaborado teve desempenho satisfatório, com coeficientes de eficiência de Nash-Sutcliffe médios de 0,69; indicador de concordância médio de 0,92; erro médio na vazão de pico equivalente à 21% e erro médio no tempo de pico igual a 2 minutos e 40 segundos. / Since the beginning of the formation of urban conglomerates in Brazil, the urban drainage has been taken a sanitary approach. This practice has caused more and more problems, such as flooding and eutrophication of streams. The constant problem faced by most cities is the strong neglect that lies in this country. In this perspective, the present work proposes a Hydraulic/hydrological model of the storm water network of Ilha Solteira, in order to support future subsidization of urban basin management as a whole. The study area was the sub-basin of the Sem Nome stream located in the city of Ilha Solteira-SP. The used database was obtained by city hall studies, field trials, probes and rain gauges installed in the project area; the satellite images were obtained by using the Free Software EarthPro., ArcGis 10 and Stormwater Management Model (SWMM), to establish a representative digital model of the basin using the Saint-Venant 1D equations and the kinematic waveform. Sensitivity, calibration and validity analyses of the system were performed, 31 events were captured and a model was evaluated by five statistic indicators. The results have shown that the elaborated model has presented a satisfactory performance with mean Nash-Sutcliffe efficiency coefficients of 0.69, index of agreement of 0,92, average error in peak flow equivalent to 21% and mean error with no peak time equal to 2 minutes and 40 seconds.
9

Precipitation Estimation Methods in Continuous, Distributed Urban Hydrologic Modeling

Woodson, David 19 June 2019 (has links)
Quantitative precipitation estimation (QPE) remains a key area of uncertainty in hydrological modeling, particularly in small, urban watersheds which respond rapidly to precipitation and can experience significant spatial variability in rainfall fields. Few studies have compared QPE methods in small, urban watersheds, and studies which have examined this topic only compared model results on an event basis using a small number of storms. This study sought to compare the efficacy of multiple QPE methods when simulating discharge in a small, urban watershed on a continuous basis using an operational hydrologic model and QPE forcings. The Research Distributed Hydrologic Model (RDHM) was used to model a basin in Roanoke, Virginia, USA forced with QPEs from four methods: mean field bias (MFB) correction of radar data, kriging of rain gauge data, uncorrected radar data, and a basin-uniform estimate from a single gauge inside the watershed. Based on comparisons between simulated and observed discharge at the basin outlet for a 6-month period in 2018, simulations forced with the uncorrected radar QPE had the highest accuracy, as measured by root mean square error (RMSE) and peak flow relative error, despite systematic underprediction of the mean areal precipitation (MAP). Simulations forced with MFB corrected radar data consistently and significantly overpredicted discharge but had the highest accuracy in predicting the timing of peak flows. / Master of Science / Estimating the amount of rain that fell during a precipitation event remains a key source of error when predicting how much stormwater runoff will be produced, particularly in small, urban watersheds which respond rapidly to precipitation and can experience significant spatial variability in rainfall distribution. Rainfall estimation in small, urban watersheds has received relatively little attention, and studies which have examined this topic have generally only examined a small number of discrete storm events. This study sought to compare the efficacy of multiple precipitation estimation methods when simulating discharge in a small, urban watershed on a continuous basis using an operational hydrologic model and precipitation inputs. The Research Distributed Hydrologic Model (RDHM), commonly used by the National Weather Service, was used to model a basin in Roanoke, Virginia, USA forced with rainfall estimates from four methods: mean field bias (MFB) correction of radar data, kriging of rain gauge data, uncorrected radar data, and a basin-uniform estimate from a single gauge inside the watershed. Based on comparisons between simulated and observed discharge at the basin outlet for a 6-month period in 2018, simulations forced with the uncorrected radar QPE had the highest accuracy, as measured by several performance statistics, despite systematic underprediction of actual precipitation. Simulations forced with MFB corrected radar data consistently and significantly overpredicted discharge but had the highest accuracy in predicting the timing of peak flows.
10

Complex, deterministic hydrological modelling towards decision support for urban catchment management

Males, Ryan James 12 1900 (has links)
Thesis (M.ScEng.)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Historically, urban waterresources have too often been managed without recognition that the flow in a river integrates many landscape and biological features. This has often resulted in the elimination of natural processes and their replacement by man-made streamlined structures with the effects of increased urbanisation being primarily addressed from an engineering and economics point of view to the detriment of environmental and social issues. Catchment Management, as legislated in the Water Act, No. 36 of 1998, is a management approach to address the negative consequences of an urban stormwater design philosophy restricted to flood restriction. It is a systems approach that integrates engineering and scientific skills, socio-economic concerns, and environmental constraints within a new multidisciplinary decision-making process that recognises the different components of the hydrological and aquatic cycles are linked, and each component is affected by changes in every other component. In order to make effective management decisions, catchment managers require tools to provide reliable information about the performance of alternative arrangements of stormwater management facilities and to quantify the effects of possible management decisions on the water environment. A deterministic hydrological model is such a tool, which provides the link between the conceptual understanding of the physical catchment characteristics and the empirical quantification of the hydrological, water quality and ecological response. In order to provide effective computer based decision support, the hydrological model must be part of an integrated software application in which a collection of data manipulation, analysis, modelling and interpretation tools, including GIS, can be efficiently used together to manage a large potion of the overall decision process. This decision support system must have a simple and intuitive user interface able to produce easily interpreted output. It must have powerful graphical presentation capabilities promoting effective communication and be designed to solve ill-structured problems by flexibly combining statistical analysis, models and data. The Great Lotus River canal, situated on the Cape Flats, Cape Town, has been designed and controlled through extensive canalisation and the construction of detention pond facilities to avoid the flooding of urban areas of the catchment. This approach has resulted in these channels becoming stormwater drains, transporting waste and nutrients in dissolved and particulate forms, and reducing their assimilatory capacity for water quality improvement. In order to investigate the use of hydrological modelling in decision support for Catchment Management, the semi-distributed, physically based model, SWMM, was applied to the Great Lotus River canal. SWMM consists of a number of independent modules allowing the hydrological and hydraulic simulations of urban catchments and their conveyance networks on an event or continuous basis. In order to ease the application of the Fortran based SWMM model, the GUl, PCSWMM98, was developed by Computational Hydraulics Inc (CH!). This provides decision support for SWMM through large array of tools for file management, data file creation, output visualisation and interpretation, model calibration and error analysis and storm dynamic analysis thus easing any simulations with SWMM. In addition, PCSWMM was developed with a GIS functionality for graphically creating, editing and/or querying SWMM model entities and attributes, displaying these SWMM layers with background layers and dynamic model results, and exporting data to SWMM input files thus providing an interface between a GIS and SWMM. In terms of Catchment Management, the above DSS can be used effectively to assist decisionmaking. This is to address tensions between the fundamental catchment management considerations of physical development, social considerations and maintaining ecological sustainability. It is at the stages of Assessment and Planning that the model can play the most significant role in providing decision support to the Catchment Management process. Assessment in the Catchment Management process refers to the collection, storage, modelling and interpretation of catchment information. It is in this quantification, interpretation and assessment of catchment information that a hydrological model contributes to an increase in knowledge in the Catchment Management process. In identifying and quantifying, at a sufficient temporal and spatial scale, the dominant cause and effect relationships in the urban physical environment, a hydrological model is able to highlight the main contributing factors to an issue. This is used in the Planning stage of the Catchment Management process and when combining these contributing factors with assessments of the socio-economic and administrative environments, enables the prioritisation of the principal issues requiring attention in a Catchment Management Strategy. It is possible to link the multiple decision-making requirements of Catchment Management with the abilities of a hydrological model to provide information on these requirements in a conceptual framework. This framework consists of the fundamental catchment considerations of Physical Development, Environmental Management and Social Development and resolves these considerations into the various management issues associated with each consideration ~s well as its management solution. The management solutions are linked to the model through formulating the solution in terms of the model parameters and perturbing the affected parameters in ways to simulate the management solution. This results in model output and graphical interpretation of the effects of the suggested management solution. A comparison between the simulated effects of each management solution allows the Catchment Management body to identify optimal management solutions for the various management Issues. The present model of the Great Lotus River catchment is sufficient to simulate the overland and subsurface flows from individual parts of the catchment and to route these flows and associated pollutant loadings to the catchment outlet. At its present level of complexity, the finely discretised model subcatchment and conveyance network provides decision support for Catchment Management through the simulation, at a pre-feasibility stage, of various Catchment Management issues and their proposed solutions. Given more detailed canal and drainage network dimensions and water quality data, it is possible for the model to incorporate hydraulic calculation routines to assess the implications of alternative river rehabilitation techniques and waste management strategies. This would allow greater capability in assessing the role of the various BMPs in ameliorating stormwater impacts and pollutant loading. In addition, a detailed level survey of the stormwater pipe and canal network could result in hydrological modelling being utilised to identify critical areas where stormwater upgrading would be necessary. In order to facilitate future complex, finely discretised catchment hydrological models, it is imperative that complete and detailed drainage patterns and stormwater network characteristics are available. In addition, to minimise model generation costs and time of model setup, this spatially representative data must be captured in a GIS for rapid inclusion into the model. Furthermore, complete spatially representative precipitation datasets are necessary to ensure that model error is reduced. These two issues of available spatial data and comprehensive precipitation records are crucial for the generated models to function as effective decision support systems for Catchment Management. / AFRIKAANSE OPSOMMING: Histories is stedelike waterbronne te dikwels bestuur sonder inagneming dat die vloei van die rivier baie landskap- en biologiese kenmerke insluit. Dit het dikwels daartoe gelei dat natuurlike prosesse uitgeskakel is en vervang is deur mensgemaakte, stroombelynde strukture waarvan die effek van toenemende verstedeliking hoofsaaklik aangespreek word vanuit 'n ingenieurs- en ekonomiese oogpunt tot nadeel van omgewings- en sosiale kwessies. Opvangsgebiedsbestuur, soos bepaal deur die Waterwet, Wet 36 van 1998, is 'n bestuursbenadering om die negatiewe gevolge van 'n stedelike stormwaterontwerpfilosofie wat beperk is tot vloedbeperking aan te spreek. Dit is 'n stelselbenadering wat ingenieurs- en wetenskaplike vaardighede, sosio-ekonomiese probleme en omgewingsbeperkings integreer in 'n nuwe multidissiplinêre besluitnemingsproses wat erkenning daaraan gee dat die verskillende komponente van die hidrologiese en watersiklusse verbind is, en elke komponent beïnvloed word deur veranderings in elke ander komponent. Om doeltreffende bestuursbesluite te neem, benodig opvangsgebiedsbestuur die hulpmiddels om betroubare inligting oor die prestasie van alternatiewe moontlikhede VIr stormwaterbestuurfasiliteite en om die effek van moontlike bestuursbesluite op die wateromgewing te kwantifiseer. 'n Deterministiese hidrologiese model is so 'n hulpmiddel wat die skakel daarstel tussen die konseptueie begrip van die fisiese opvangsgebiedskenmerke en die empiriese kwantifisering van die water-, waterkwaliteit- en ekologiese reaksie. Om doeltreffende rekenaarbesluitnemingsteun te verskaf, moet die hidrologiese model deel wees van 'n geïntegreerde sagteware-aanwending waarin 'n versameling datamanipulasie-, analise-, modellerings- en interpreteringshulpmiddels, insluitend GIS, doeltreffend saam gebruik kan word om 'n groot deel van die algehele besluitnemingsproses te bestuur. Hierdie besluitnemingsteunstelsel moet 'n eenvoudige en intuïtiewe gebruikersvlak hê wat in staat is om maklik interpreteerbare uitsette te lewer. Dit moet goeie grafiese voorleggingsvermoëns hê wat doeltreffende kommunikasie vergemaklik en ontwerp wees om swak gestruktureerde probleme deur die buigsame samevoeging van statistiese analise, modelle en data op te los. Die Groot Lotusrivierkanaal op die Kaapse Vlakte, Kaapstad is ontwerp en word beheer deur uitgebreide kanalisasie en die konstruksie van detensiedamfasiliteite om die oorstroming van stedelike opvangsgebiede te vermy. Hierdie benadering het daartoe gelei dat hierdie kanale stormwaterafvoerpype geword het wat afval en nutriënte in opgelosde en partikelvorm vervoer en hulle assimilasievermoë vir die verbetering van waterkwaliteit verminder. Om die gebruik van hidrologiese modelle in besluitnemingsteun vir Opvangsgebiedsbestuur te ondersoek, is die semi-verspreide, fisiesgebaseerde model, SWMM, op die Groot Lotusrivierkanaal toegepas. SWMM bestaan uit 'n aantalonafhanklike modules wat die hidrologiese en hidroulika simulasies van stedelike opvangsgebiede en hulle vervoemetwerke per geleentheid of deurlopend monitor. Om die aanwending van die Fortran gebaseerde SWMM model te vergemaklik is die GUl, PCSWMM98 deur Computational Hydraulics Inc (CHD ontwikkel. Dit verskaf besluitnemingsteun vir SWMM deur 'n groot aantal hulpmiddels vir lêerbestuur, die skep van datalêers, uitsetvisualisering en interpretasie, modelkalibrasie, foutanalise en stormdinamikaanalise om enige simulasies met SWMM te vergemaklik. Daarby is PCSWMM ontwikkel met 'n GIS funksionaliteit vir die grafiese daarstelling, redigering en/of navraagfunksie van SWMM model entiteite en kenmerke, wat hierdie SWMM vlakke met agtergrondvlakke en dinamiese modelresultate vertoon en data in SWMM inset1êers plaas en op daardie manier 'n koppelvlak tussen 'n GIS en SWMM verskaf. Volgens Opvangsgebiedsbestuur kan bogenoemde DSS doeltreffend gebruik word in besluitneming. Dit IS om die spanning tussen fundamentele opvangsgebiedsbestuursoorwegings van fisiese ontwikkeling, sosiale oorwegings en ekologiese volhoubaarheid aan te spreek. Dis in die stadiums van Waardebepaling en Beplanning wat die model die belangrikste rol kan vervul in die verskaffing van besluitnemingsteun vir die Opvangsgebiedsbestuursproses. Waardebepaling in die Opvangsgebiedbestuursproses verwys na die versameling, berging, modellering en interpretasie van opvangsgebiedsinligting. Deur hierdie kwantifisering, interpretasie en waardebepaling van opvangsgebiedsinligting dra 'n hidrologiese model by tot 'n verhoging in kennis in die Opvangsgebiedsbestuur. Deur die identifisering en kwantifisering, op 'n ruim genoeg tydelike en ruimtelike skaal, van die dominante oorsaak en gevolg verhoudings in die stedelike fisiese omgewing, kan die hidrologiese model die hoof bydraende faktore uitlig. Dit word gebruik in die Beplanningsfase van die Opvangsgebiedproses en wanneer hierdie bydraende faktore by die waardebepaling van die sosio-ekonomiese en administratiewe omgewings saamgevoeg word, maak dit moontlik om die belangrike kwessies wat aandag behoort te kry in 'n Opvangsgebiedsbestuurstrategie in volgorde van voorrang te plaas. Dit is moontlik om die verskeidenheid besluitnemingsvereistes van Opvangsgebiedsbestuur met die vermoëns van 'n hidrologiese model te koppel om inligting oor hierdie vereistes in 'n konseptuele raamwerk te verskaf. Die raamwerk bestaan uit die fundamentele opvangsgebiedsoorwegings van Fisiese Ontwikkeling, Omgewingsbestuur en Sosiale Ontwikkeling en los hierdie oorwegings op in die verskillende bestuursaangeleenthede wat met elke oorweging en die bestuuroplossing geassosieer word. Die bestuursoplossings word aan die model gekoppel deur die formulering van die oplossing volgens die modelparameters en versteuring van die relevante parameters op sekere manier om die bestuursoplossing te simuleer. Dit lei tot modeluitset en grafiese interpretasie van die effek van die voorgestelde bestuursoplossing. 'n Vergelyking tussen die gesimuleerde effek van elke bestuursoplossing laat die Opvangsgebiedsbestuursliggaam toe om die optimale bestuursoplossings vir die verskeie bestuursaangeleenthede te identifiseer. Die huidige model van die Groot Lotusrivieropvang is genoegsaam om die bo- en ondergrondse vloei vanaf individuele dele van die opvangsgebied te simuleer en om die watervloei en geassosieerde besoedelstofladings na die opvangsgebiedsuitlaatplek te lei. Op sy huidige vlak van kompleksiteit verskaf die fyn gediskretiseerde model subopvangsgebied en vervoernetwerk besluitnemingsteun aan Opvangsgebiedsbestuur deur die simulasie, teen 'n voor-lewensvatbaarheidstudie, van verskeie opvangsgebiedsbestuurkwessies en die voorgestelde oplossings. Indien meer gedetailleerde kanaal- en dreineringsnetwerkdimensies- en waterkwaliteitdata ingevoer word, is dit moontlik vir die model om hidroulikaberekeningsroetines te inkorporeer om die implikasies van alternatiewe rivierrehabilitasietegnieke en afvalbestuurstrategieë te beoordeel. Dit sou die vermoë verbeter om die waarde van die verskeie BMPs te bepaal om die impak van stormwater en besoedelstoflading te versag. Daarby kan 'n gedetailleerde vlakopname van die stormwaterpyp en -kanaalnetwerk daartoe lei dat hidrologiese modelle gebruik kan word om kritieke areas te identifiseer waar stormwateropgradering nodig is. Om toekomstige komplekse, gediskretiseerde opvangsgebiedshidrologiese modelle te verbeter, is dit noodsaaklik dat volledige en gedetailleerde dreineringspatrone en stormwaternetwerkkenmerke beskikbaar is. Om die model-ontwikkelingskoste en tyd bestee aan die opstel van 'n model te minimiseer, moet hierdie ruimtelik verteenwoordigende data ingelees word in 'n GIS vir vinnige insluiting in die model. Daarbenewens is volledige, ruimtelik verteenwoordigende presipitasie datastelle nodig om te verseker dat modelfoute verminder word. Hierdie twee kwessies van beskikbare ruimtelike data en omvattende presipitasierekords is van die uiterste belang sodat die gegenereerde modelle as doeltreffende besluitnemingsteun vir Opvangsgebiedsbestuur kan funksioneer.

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