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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.
11

Evaluation of a constructed dry swale for treatment of stormwater runoff /

Wilson, Laura R., January 2004 (has links)
Thesis (M.S.) in Ecology and Environmental Science--University of Maine, 2004. / Includes vita. Includes bibliographical references (leaves 67-74).
12

Investigation of deterioration models for stormwater pipe systems

Tran, Huu Dung. January 2007 (has links)
Thesis (Ph.D.)--Victoria University (Melbourne, Vic.), 2007.
13

Extended stormwater detention basin design for pollutant removal /

Watkins, Edwin W., January 1993 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 110-112). Also available via the Internet.
14

Stormwater Management for Urban Areas

Chancellor, Gerald L. 01 January 1975 (has links) (PDF)
Stormwater management in urban areas is a major concern today. The problem of disposing of this stormwater runoff in a satisfactory manner is very difficult indeed. Both the quantity and quality aspects of the runoff must be dealt with to obtain a solution of this problem. The water quality of the runoff can vary depending upon the different land uses of the drainage basin. The quantity of the stormwater runoff also depends upon the land uses, the rainfall intensity and duration of the storm. The traditional methods available for determining the quantity of the stormwater runoff are numerous. These traditional methods and recently developed mathematical simulation models are discussed in this paper. Prediction of the water quality of stormwater runoff is in its infancy. Several of the mathematical models have the capabilities of quality simulation, however, the simulation results are usually inconsistent with actual quality data. Of the simulation models currently in use, the EPA Storm Water Management Model is one of the most comprehensive models. Application and verification of these newly developed models is limited. The EPA Model was chosen to simulate the quantity and quality of a small urban drainage area. The study area chosen was an urban commercial section of the Lake Eola drainage basin. Physical data of the study area, such as ground slopes, storm sewer sizes and locations and slopes were determined. This data was then utilized for simulations of actual rainfall events. Verification of the quantity and quality simulation results was performed with actual quantity and quality data obtained for these rainfall events. Quantity simulation was considered successful with good correlation between the simulated and actual runoff. Quality simulation was successful to a lesser degree, the conclusion being that further quality calibration of the Model was required. Correlation between actual and simulated stormwater quality was achieved to some extent. The lack of correlation was felt to be due to calibration of the Model.
15

Evaluation of the effectiveness of BMP's for urban stormwater management: single-event simulation

Cave, Kelly A. January 1986 (has links)
A desk top model has been developed for "user-friendly" application in personal computers to simulate watershed response to a rainfall event in terms of runoff generation and to estimate nonpoint source pollutant loadings associated with the storm event. The algorithms utilize the SCS TR - 55 method for calculating runoff hydrographs for a single storm event. A methodology has been adapted to generate pollutographs which combines the SCS Type II rainfall distribution with the standard pollutant washoff equations. In addition, this model allows for the design, evaluation, and cost effectiveness analysis of various best management practice (BMP) measures as tools to manage stormwater quantity and quality. / M.S.
16

Verification of the inlet capacities of modified stormwater kerb inlets and the development of new design curves

Grobler, Pieter 03 1900 (has links)
Thesis (MEng)--Stellenbosch University, 1994. / ENGLISH ABSTRACT: Various aspects affecting the inlet capacities of modified stormwater kerb inlets were investigated. Investigations centred on the influence of effective inlet length, ratios of upstream transition section length to inlet section length and road crossfall. The suitability of existing design curves for use in the design of modified kerb inlets was verified and new more "user-friendly" design curves were developed. Attempts were made to develop a sound theoretical model to predict inlet capacities for stormwater kerb inlets as the lack of such a model had previously been identified as a major shortcoming in the design of stormwater kerb inlets. A detailed study of relevant literature and of various full scale model test results confirmed the fact that the effective inlet length is the most important variable affecting the inlet capacity at stormwater kerb inlets. Model studies on various combinations of transition section lengths and inlet section lengths have indicated that in the case of supercritical flow the inlet capacity of stormwater kerb inlets is not sensitive to changes in the ratio between the inlet section length and the upstream transition section length. Furthermore no marked effect on the inlet capacity of a modified stormwater kerb inlet was detected when the road crossfall was increased from 2% to 3%. The inlet capacities predicted by the existing design curves were found to be consistent, although on the conservative side, when compared to the inlet capacities obtained from the full scale model tests. New design curves derived from the existing design curves were developed to provide a less cumbersome procedure in the design of stormwater kerb inlets. The development of an improved comprehensive theoretical model based on pure hydraulic principles was not possible due to the extremely complex nature of flow conditions at stormwater kerb inlets. The most important findings emanating from this research project are: - The confirmation of the "effective inlet length” concept, whereby a part of the expensive inlet section is replaced by an equivalent length of inexpensive transition section upstream of the kerb inlet. which does not affect the inlet capacity of the kerb inlet negatively and thereby results in a substantial saving in the cost of stormwater kerb inlets. - Model tests revealed that for supercritical flows the upstream transition section can be made up to 6 times longer than the inlet section with a maximum length of 6m. without any negative effect on the inlet capacity of the kerb inlet. Similarly an analysis of previous research results has indicated that even in cases of subcritical flow the upstream transition section can be made twice the length of the inlet section. - The full scale model tests also indicated that an upward adjustment of 30% in the inlet capacities as predicted by the existing design curves was justified. The modified design curves proved to be suitable for the design of conventional stormwater kerb inlets as well as for modified stormwater kerb inlets where part of the inlet section is replaced by a transition section. A new set of "easy to use" design curves was developed specifically for urban applications. - Guidelines for determining upstream transition section lengths were drawn up for use in conjunction with the existing and new design curves for the design of stormwater kerb inlets. / AFRIKAANSE OPSOMMING: Verskeie aspekte wat die inlaatkapasiteit van verbeterde randsteeninlate belnvloed is ondersook. Die belangrikste aspekte wat ondersoek is, was die invlood van effektiewe inlaatlengte en die moontlike verhouding van die stroomop oorgangslengte tot die werklike inlaatlengte sowel as dwarshelling. Die ontwerpgrafieke wat tans gebruik word om randsteeninlaatlengtes te bepaal is ook ondersoek aan die hand van modeltoetse op volskaalse modelle om die grafieke se akkuraatheid te toots. Meer gebruikersvriendelike ontwerpgrafieke is ook ontwikkel. 'n Belangrike tekortkoming tot op datum, naamlik 'n geskikte teoretiese model om die inlaatkapasiteit van randsteeninlate te beskryf, is aangespreek. 'n Voorvereiste vir so 'n model was dat die model gebaseer moes word op suiwer hidrouliese beginsels. Die bestudering van vorige navorsing asook die uitvoering van verskeie modelstudies op volskaalse randsteeninlate het die effektiewe inlaatlengte as die belangrikste veranderlike wat die inlaatkapasiteit van randsteeninlate bepaal geYdentifiseer. Tydens tootse uitgevoer op volskaalse modelle onder superkritiese vlooitoostande met verskillende kombinasies van oorgangslengtes en inlaatlengtes, vir die dieselfde totale lengte het dit geblyk dat die inlaatkapasiteit grootliks onatbanklik is van die verhouding van die oorgangslengte tot die inlaatlengte. Vit die modeltootse het dit oak geblyk dat paddwarsval 'n baie beperkte invlood op die inlaatkapasiteit van ransteeninlate gehad het toe die paddwarsval verander is van 2%na 3%. Die resultate wat verkry is uit die modeltoetse het ook aangetoon dat die bestaande ontwerpgrafieke konserwatief is in hul voorspelling van inlaatkapasieit van randsteeninlate. Die bestaande ontwerpgrafieke is voorts gebruik om nuwe meer gebruikersvriendelike ontwerpgrafieke te ontwikkel. Die ontwikkeling van 'n teoretiese model am inlaatkapasiteite volledig te voorspel was egter nie moontlik nie vanwee die uiters komplekse aard van die vloei by randsteeninlate. Die belangrikste bevindinge van hierdie studie kan soos volg opgesom word: - Afdoende bewyse is gevind dat die "effektiewe inlaatlengte" konsep, waarvolgens 'n gedeelte van die duur inlaatgedeelte met 'n goedkoper oorgangsstuk van dieselfde Iengte vervang kan word sonder om inlaatkapasiteit in te boet, weI suksesvol aangewend kan word om kostes in die ontwerp van stOlIDwater randsteeninlate te bespaar. - Afdoende bewyse is gevind dat die "effektiewe inlaatlengte" konsep, waarvolgens 'n gedeelte van die duur inlaatgedeelte met 'n goedkoper oorgangsstuk van dieselfde Iengte vervang kan word sonder om inlaatkapasiteit in te boet, weI suksesvol aangewend kan word om kostes in die ontwerp van stOlIDwater randsteeninlate te bespaar. - Afdoende bewyse is gevind dat die "effektiewe inlaatlengte" konsep, waarvolgens 'n gedeelte van die duur inlaatgedeelte met 'n goedkoper oorgangsstuk van dieselfde Iengte vervang kan word sonder om inlaatkapasiteit in te boet, weI suksesvol aangewend kan word om kostes in die ontwerp van stOlIDwater randsteeninlate te bespaar. - Riglyne is ook ontwikkel vir die bepaling van stroomop oorgangslengtes. Die riglyne kan saam met die bestaande en die nuwe ontwerpgrafieke gebruik word by die ontwerp van stormwater nmdsteeninlate.
17

Effect of urban street pattern on drainage.

Kao, Samuel Erh-chiang,1944- January 1973 (has links)
In cities, storm runoff is usually collected in the streets and conveyed to underground storm drains through inlets located at street level. Construction and maintenance of storm drain systems is always expensive. In semiarid regions with a very low frequency of storm occurrence, most cities use streets as the drainage route even though their primary function is for the movement of traffic. As a result, the shape of a runoff hydrograph at the outlet of an urban watershed will vary with the pattern of street arrangement within the watershed. The objective of this study is to investigate tradeoffs between alternative street patterns with respect to urban drainage. The study area is confined to residential subdivisions where the subdivision boundary is assumed to be the watershed boundary. Three street patterns, namely, rectangular, curvilinear and dendritic, are considered in this study. The cost-effectiveness technique is employed to give an objective evaluation for these three alternative patterns. The effectiveness is measured by three kinds of evaluators. The first evaluator is the flow depth at certain points on the streets; the second evaluator is the total time during which the streets are occupied by a certain depth of water; the third evaluator is the total cost associated with the construction of a street pattern. A framework of a distributed system model has been constructed for simulating the runoff hydrographs and flow depths at certain points on the streets. A parcel of land near Willcox, Arizona, is selected to illustrate how the model could be used. Possible subdivisions of the land for each of the three different types of street patterns are shown, and the runoff hydrographs and flow depths from each of the patterns are examined. It is found that the peak flow rate resulting from the rectangular pattern is 13 percent higher than that from the curvilinear pattern and 29 percent higher than that from the dendritic pattern. The dendritic pattern has the smallest percentage of street intersections occupied by water during a storm. Time of occupation of high water stages at street intersections is much shorter in the dendritic pattern than that in the rectangular and curvilinear patterns. The development cost for the dendritic pattern is the lowest among these three patterns. Therefore, the dendritic pattern appears to be the best type of street arrangement in terms of urban drainage.
18

Land use changes and the properties of stormwater entering a wetland on a sandy coastal plain in Western Australia /

Kobryń, Halina T. January 2001 (has links)
Thesis (Ph.D.)--Murdoch University, 2001. / Thesis submitted to the Division of Science and Engineering. Bibliography: leaves 205-222.
19

Stormwater impacts on disharge water quality in licensed drains at the Port Kembla Steelworks

Whant, Louis Mathew. January 2005 (has links)
Thesis (M.Env.Sc.)--University of Wollongong, 2005. / Typescript. Includes bibliographical references: leaf 81-84.
20

Sources of nitrogen and phosphorus in stormwater drainage from established residential areas and options for improved management

Khwanboonbumpen, S. January 2006 (has links)
Thesis (Ph.D.)--Edith Cowan University, 2006. / Submitted to the Faculty of Computing, Health and Science. Includes bibliographical references.

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