Thèses sur le sujet « Urban runoff Vietnam Management »

In the Greater Vancouver Regional District (GVRD), non-point source pollution from an urban watershed and a diesel bus loop was assessed in terms of trace metal contamination in the stormwater runoff. In the Brunette River watershed study, Northwest Hydraulic Consultants (NHC) collected streambed sediment and suspended sediment from selected streams during 7 storm events over 2003. From 1993 to 2003, the major stormwater contamination happened in the most industrialized Still Creek. The streambed Cu, Mn, Fe, and Zn concentration increased by 1.5, 1.7, 1.9, and 1.1 times, respectively. And the suspended Cu, Mn, and Zn increased by a factor of 2.1, 4.2, and 1.5, respectively. The streambed sediment exceeded probable effect level in Still Creek and Stoney Creek to varying degrees with Cu and Zn. The land use is considered to be the origins of these toxicants. Statistically, the magnitude of suspended metal concentration in μg/l is negatively correlated with the drainage areas. While the — concentrations in mg/kg, especially for metal Cu and Zn, showed strongly and positively correlation with the traffic density. Positive correlation existed between the suspended metal loading (kg/yr) and the imperviousness and the catchment area. No apparent trend was observed in terms of export coefficient (g/ha/yr) and land use. 1062 tons of sediments were trapped by Burnaby Lake in 2003. This sediment overloading problem causes serious metal contamination in the lake. Stormwater runoff quality was monitored in 15 storm events from October 2004 to June 2005 in the diesel bus loop in the University of British Columbia. The dissolved Cu and Zn Event Mean Concentration (EMC) exceeded the EPA discharge criteria in 2 and 4 events each, which occurred in the dry season. Diesel bus traffic contributes' a large portion of Cu, Fe, Zn contamination since the average bus loop trace metal levels were much higher than the GVRD urban levels. The runoff trace metal concentrations are strongly related to the antecedent dry period, and are weakly related to the traffic density and the rainfall intensity. From the catch basin filter evaluation, high removal efficiencies on suspended metal/solids were achieved with low particulate loading in the filter chamber. The filter performed well for the dissolved metal removal before the non-reversible saturation was reached. Each kilogram of filter media has an absorption capacity of 52 gram oil and grease, 20 milligram Mn, and 16 milligram Zn.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

Sustainable Built Environments Senior Capstone Project
During Tucson rainstorms, many roads and neighborhoods experience high levels of flooding on the city’s street networks. This phenomenon creates unsafe road conditions, damage to the road infrastructure, and excessive urban stormwater runoff that is potentially polluted. The vast quantities of impervious surfaces in the urban landscape impede the rainwater’s ability to infiltrate the ground, thus resulting in increased volumes of runoff during a rainstorm. Stormwater management is used by municipalities and communities to address the previously mentioned adverse impacts of stormwater runoff. Various techniques and strategies used in stormwater management include, low impact development (LID), green infrastructure, and better site design (BSD) strategies implemented during design stages to reduce stormwater runoff levels. In addition, local governments can establish stormwater utilities and policies in order to help address and better manage the issue of stormwater runoff within urban areas. The primary research questions of this study will include: What are the most effective best management practices and techniques to address urban runoff? What combination of best management practices and government policies will be the more effective in addressing Tucson’s urban runoff problem? Accordingly, this study will examine a variety of policies and techniques to address stormwater runoff, and then, based on this information, provide a suggestion of the best practices and techniques that may be feasible for implementation in Tucson.

Stormwater management is always a problem in Hong Kong since its development from a fishing village. Contributed by abundant precipitation, hilly topography, and dense urban development, flooding has been causing enormous economic losses to Hong Kong and is a main focus of local stormwater management. With the construction of many conventional hardcore engineering stormwater management structures in recent decades, such as underground detention tanks and stormwater tunnels, the flooding problem in Hong Kong has been well alleviated. It is now the time to move forward and incorporate more sustainable stormwater management principles and techniques, namely the strategy of low-impact development (LID), into the local practices in Hong Kong. Stormwater should be viewed not only as a problem, but also as a valuable resource. This research aims at a feasibility study on the possible applications and hydrologic benefits of bioretention and permeable pavements under the local conditions of Hong Kong. The buildability of infiltration devices in Hong Kong is examined by constructing pilot-scale physical models of both bioretention and permeable pavements in this study. Hydrologic monitoring of these physical models under Hong Kong rainfall events is carried out for at least one wet season. The monitoring data are analyzed to evaluate the hydrologic performance of bioretention and permeable pavements, as indicated by peak flow reduction and volume retention of stormwater runoff. The long-term hydrologic performance is also evaluated by the numerical model SWMM (Stormwater Management Model). After model calibration and validation using field data on the physical model, SWMM isused to simulate bioretention performance for the past ten year precipitation records of Hong Kong under systematic variations of two relevant parameters, namely the exfiltration rate and the area ratio of bioretention to catchment. Results show that both bioretention and permeable pavements are feasible to be applied in Hong Kong. The hydrologic performance of bioretention is influenced by the precipitation patterns, the size of bioretention, the stormwater storage, and the properties of soil. As in common practice, the available storage of bioretention is much smaller than design rainfalls in Hong Kong. Therefore, peak flow reduction shall not be the target of incorporating bioretention in local storm drain designs. The influence on long-term water balance in the urban area may be considered as the main benefits from bioretention, using the annual retention ratio as a performance indicator. The hydrologic performance of permeable pavements is influenced by the storage depth provided by the gravel layer and the properties of in-situ soil. Considerably good peak flow reduction and volume retention are obtained in the experimental permeable pavements subjected to the local extreme precipitation events. In actually applications, the storage of permeable pavement may be designed to capture the total depth of design storms in Hong Kong, after which peak flow reduction may be obtained. It is anticipated that this research can provide reference information on both the design and hydrologic benefit estimation of bioretention and permeable pavements practices for applications in Hong Kong.
published_or_final_version
Civil Engineering
Master
Master of Philosophy

Thesis (Ph. D.)--University of Alabama at Birmingham, 2009.
Additional advisors: Robert Angus, Paul D. Blanchard, Sarah Culver, Alan Shih. Description based on contents viewed June 3, 2009; title from PDF t.p. Includes bibliographical references (p. 48-51).

[Truncated abstract]This thesis investigates aspects of urban stormwater modeling and uses a small urban catchment (NE38) located in the suburb of Nedlands in Perth, Western Australia to do so. The MUSIC (Model for Urban Stormwater Improvement Conceptualisation) model was used to calibrate catchment NE38 using measured stormwater flows and rainfall data from within the catchment. MUSIC is a conceptual model designed to model stormwater flows within urban environments and uses a rainfall-runoff model adapted to generate results at six minute time steps. Various catchment scenarios, including the use of porous asphalt as an alternative road surface, were applied to the calibrated model to identify effective working stormwater disposal systems that differ from the current system. Calibrating catchment NE38 using the MUSIC model was attempted and this involved matching modeled stormwater flows to stormwater flows measured at the catchment drainage point. This was achieved by measuring runoff contributing areas (roads) together with rainfall data measured from within the catchment and altering the seepage constant parameter for all roadside infiltration sumps. ... The MUSIC model generated future scenario outcomes for alternative stormwater disposal systems that displayed similar or improved levels of performance with respect to the current system. The following scenarios listed in increasing order of effectiveness outline future stormwater disposal systems that may be considered in future urban design. 1. 35% porous asphalt application with no sumps in 2036 2. 35% porous asphalt application with no sumps in 2064 3. 68% porous asphalt application with no sumps in 2036 4. 68% porous asphalt application with no sumps in 2064. Future scenarios using the current stormwater disposal system (with roadside infiltration sumps) with porous asphalt were also run. These scenarios reduced stormwater runoff and contaminant loading on the catchment drainage point however the inclusion of a roadside infiltration sump system may not appeal to urban designers due to the costs involved with this scenario. Climate change will affect the design of future stormwater disposal systems and thus, the design of these systems must consider a rainfall reducing future. Based on the findings of this thesis, current stormwater runoff volumes entering catchment drainage points can be reduced together with contaminant loads in urban environments that incorporate porous asphalt with a stormwater disposal design system that is exclusive of roadside infiltration sumps.

Stormwater treatment is commonly performed with a combination of approaches including the utilization of natural systems and engineered devices. Before using a proprietary treatment instrument it is required to verify its performance and efficiency in reducing different pollution components including the TSS. Different states have developed strategies and regulations for accepting new instruments. In this thesis the stormwater management plan of the City of Portland, Oregon(2008), is analyzed in order to improve the current regulations. These rules apply to new technologies which are proposed by vendors to be used in Portland's stormwater treatment plans. Each requirement which should be met by the applying vendors is thoroughly analyzed followed by a comparison with the Stormwater management plan(2008)regulations of the state of Washington the so called Technology Assessment Plan-Ecology TAPE (Howie, 2011). Because of the similarities in the climate and land use between these two testing frameworks in order to evaluate the potential applicability of data submitted by vendors who had devices approved by Washington, to be utilized by Portland. The treatment of total suspended solids (TSS) is the focus of this thesis since it is central to the testing process and since most of the other pollutions are attached to TSS and will get treated if TSS is treated. The overall analysis shows that Portland adopts more restrictive requirements on the characterization of stormwater event samples to be treated by a technological instrument while Washington's restriction are more stringent on the efficiency of total suspended solid removal, in which it demands higher standards on the treatment of TSS compared to Portland's efficiency requirements. In order to study practical context in which regulations are administrated by Portland, rainfall data from 66 gauges covering the period of 1980-2011 was studied and the impacts of seasonality, land use, land form, periods of no rain before and after an event and Portland's Modified Performance line on the number of accepted rain events were analyzed. The results which were accepted by state of Washington were also compared with the results accepted by the city of Portland on Portland's Standard Performance line. Our seasonality study suggests that Portland's requirements are unnecessarily restrictive which results in the disqualification of many otherwise useful stormwater events, sometimes allowing no natural events to be available for testing in dry years. The analysis of land use showed that land use has no statistically significant impact on the concentration levels of TSS, thereby indicating that land use restrictions in the testing rules could be usefully relaxed. Decreasing the interevent no-rain period significantly increases the total number of events providing sufficient data to assess the performance of treatment facilities. We also showed that many more events become suitable for performance testing if events separated by one hours or less are considered a single, longer event. Finally we identified a statistical relationship between number of forecasted accepted stormwater events and the total average daily precipitation in a given year.

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.

Stormwater management basins (SWMB) are used to mitigate urban runoff. The Virginia Department of Transportation relies on dry detention basins planted with mowed turfgrass. However, these basins often retain water; resulting in cattail (Typha spp.) and tree colonization. Managing agencies request cattail eradication and trees are also removed. However, if trees were allowed to remain they could alter basin dynamics, making conditions unsuitable for cattails.

In a greenhouse study we tested the impact of three shade (heavy, medium, full sun) and soil moisture (dry, moist, flooded) treatments on cattail growth. After two months, cattail biomass indicated a strong interaction between soil moisture and shade (p<.0001). Increases in shade and reductions in soil moisture resulted in decreased biomass and rhizome length. Heavy shade and dry soil produced the most reductions in cattail growth (95% less biomass, 83% smaller rhizomes than cattails in full sun and flooded soil). However, considerable growth reductions still occurred in medium shade and moist soil (66% for biomass and 74% for rhizome lengths).

In a field study in four unmaintained SWMB in Virginia, environmental data (litter layer, water table, soil organic matter, etc.) and vegetation composition (cattail and other herbaceous biomass, and woody vegetation influence index) were collected from 100, 0.25-m2 plots. Principal component analysis indicated cattails and trees occupy opposing environmental spaces. Water table is most strongly correlated to cattail biomass. While these results suggest trees could eliminate cattails from SWMB, more research is needed to determine the long-term impacts of trees on basin function.
Master of Science

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.

The present paper summarizes the results of an application initiated within the framework of 35 years celebration of diplomatic relations between Germany and Vietnam. Within this context, the Technische Universität Dresden (TUD) and the Academy of Managers for Construction and Cities (AMC) jointly organized in 2010 a series of four thematic workshops. The one-day events have had similar structures and focused on main subjects of interest in the water sectors of both countries. In Vietnam, the workshops took place in Ha Noi, Hai Phong, Nha Trang and Vung Tau. Best practice examples about conceptualization, operation and maintenance of municipal water works provided an insight view into the challenges currently faced by the water service providers. TUD and AMC, together with their German and Vietnamese partners, addressed these issues by organizing the consecutive workshops under the umbrella of Vietnamese Water Supply and Sewerage Association (VWSA) and in coordination with the German Water Partnership (GWP)
Bài báo trình bày tóm tắt các kết quả của một đề xuất trong khuôn khổ kỷ niệm 35 năm quan hệ ngoại giao giữa CHLB Đức và Việt Nam. Theo đó, Trường Đại học Tổng hợp Kỹ Thuật Dresden (TUD) và Học viện Quản lý Xây dựng và Đô thị (AMC) đã phối hợp tổ chức một chuỗi bốn hội thảo chuyên đề trong năm 2010. Mỗi hội thảo thực hiện trong một ngày chương trình giống nhau và tập trung vào các chủ đề chính mà cả hai quốc gia đều quan tâm trong lĩnh vực nước. Phía Việt Nam, các hội thảo được tổ chức ở các thành phố Hà Nội, Hải Phòng, Nha Trang và Vũng Tàu. Nhiều bài thuyết trình về khái niệm hóa, vận hành và bảo dưỡng các công trình cấp nước đô thị đã thảo luận sâu về những thách thức mà các dịch vụ cấp nước đang gặp phải. TUD và AMC, kết hợp với các đối tác CHLB Đức và Việt Nam, đã ghi nhận các vấn đề phát sinh thông qua việc tổ chức nhiều hội thảo liên tục dưới sự bảo trợ của Hiệp hội Cấp thoát nước Việt Nam (VWSA) và Hiệp hội nước CHLB Đức (GWP)

Green Stormwater Infrastructure (GSI) has become a popular method for flood mitigation as it can prevent runoff from entering streams during heavy precipitation. In this study, a recently developed neighborhood in Gresham, Oregon hosts a comparison of various GSI projects on runoff dynamics. The study site includes dispersed GSI (rain gardens, retention chambers, green streets) and centralized GSI (bioswales, detention ponds, detention pipes). For the 2017-2018 water year, hourly rainfall and observed discharge data is used to calibrate the EPA's Stormwater Management Model to simulate rainfall-runoff dynamics, achieving a Nash-Sutcliffe efficiency of 0.75 and Probability Bias statistic of 3.3%. A synthetic scenario analysis quantifies the impact of the study site GSI and compares dispersed and centralized arrangements. Each test was performed under four precipitation scenarios (of differing intensity and duration) for four metrics: runoff ratio, peak discharge, lag time, and flashiness. Design structure has significant impacts, reducing runoff ratio 10 to 20%, reducing peak discharge 26 to 68%, and reducing flashiness index 56 to 70%. There was a reverse impact on lag time, increasing it to 50 to 80%. Distributed GSI outperform centralized structures for all metrics, reducing runoff ratio 22 to 32%, reducing peak discharge 67 to 69%, increasing lag time 133 to 500%, and reducing flashiness index between 32 and 62%. This research serves as a basis for researchers and stormwater managers to understand potential impact of GSI on reducing runoff and downstream flooding in small urban watersheds with frequent rain.

As urban land expands across the globe and impervious surfaces continue to be used for constructing urban infrastructure, stormwater treatment costs and environmental damage from untreated stormwater will rise. Well designed urban landscapes can employ trees and soils to reduce stormwater runoff flowing to streams and treatment facilities. Typical urban soil, however, is compacted and restricts tree growth via high soil strength and inadequate gas exchange. A site preparation method that deeply incorporates compost and includes trees for long term carbon input and pore development was evaluated in the urban setting of Arlington, Virginia. Three species were used in that study of 25 streetside plantings. The site preparation affected soil at 15 30 cm by lowering soil bulk density by 13.3%, and increasing macro-aggregate-associated carbon by 151% compared to control plots, and resulted in 77% greater tree growth during the first year after transplant. In a second experiment, rainfall simulations were used to evaluate common landscape mulch materials for their ability to prevent compaction from traffic as well their affect on surface runoff before and after traffic. When plots were subjected to heavy rainfall, (>97 mm/h) mulches were found to reduce sediment loss 82% and 73% before and after traffic, respectively. Runoff rates from wood chips were only 0.19 ml/s faster after traffic while rates from bare soil and marble gravel with geotextile increased 2.28 and 2.56 ml/s, respectively. Management of soils, trees and landscapes for stormwater benefit could reduce cost of wastewater treatment for municipalities and can prevent environmental degradation.
Master of Science

Diversion of the first flush of storm runoff to a detention basin for pollutant removal is an efficient way to control nonpoint source pollutant in urban areas. This can be achieved by a diversion box and detention basin system. To numerically simulate the response of the system to a design rainfall event and the associated pollutant loadings for a given drainage area, a desk top model has been developed for"user-friendly"' application in personal computers. Hydrographs and pollutographs are generated at the inlet and outlet of the diversion box and the detention basin.These hydrographs and pollutographs are examined and the peak outflow and peak pollutant concentrations are compared with allowable outflow and pollutant concentration for urban stormwater quality and quantity management. This model is designed for both the analysis and design of the system.
M.S.

Master of Regional and Community Planning
Department of Landscape Architecture and Regional and Community Planning
Tim Keane
The City of Manhattan, Kansas has been subject to intense flooding in the last couple of years. Areas of the city, within the Wildcat Creek Watershed, have been adversely affected. The City of Manhattan and stakeholders from various walks of life are looking for solutions to alleviate flooding within the area. This Master’s Project looks into rainwater harvesting as one of the solutions to help reduce stormwater runoff and contribute to the alleviation of flooding within the Watershed. Rainwater harvesting is increasingly being recognized as an effective way to reduce stormwater runoff. The project explores the potential benefit of using a network of rainwater harvesting elements, namely rain barrels and cisterns supplemented by rain gardens and other infiltration methods to reduce runoff in the City of Manhattan, Kansas. To assess the benefit of using rainwater harvesting in the City, a neighborhood scale site was chosen and divided into land use types. Three phases were used to assess the impact and implementation of rainwater harvesting. Phase I calculates the volume of runoff generated from each land use type and how much of that runoff can be harvested from the rooftops. The values from the neighborhood scale analysis were then extrapolated to see the impact of rainwater harvesting on a larger scale. Phase II looks at the configuration of a rainwater harvesting system for the structures in each land use type and rainwater reuse options. Finally, Phase III looks at policies, regulations and incentives that can be employed by the City of Manhattan to help encourage rainwater harvesting. This Master’s project seeks to educate the City and its residents about the benefits of rainwater harvesting as a stormwater management tool and provide steps towards potentially using rainwater harvesting as a way to reduce runoff, and help alleviate flooding in the Wildcat Creek Watershed.

The thesis covers the investigation of the storm water runoff and artificial recharge components of the Atlantis Water Resource Management Scheme in the Southwestern Cape. The objective of the study was to obtain an in-depth knowledge of the process of artificial recharge of urban storm water runoff, in order to identify the most efficient recharge management strategy for the Atlantis aquifer. To achieve the objective it was necessary to first study the existing knowledge on urban storm water hydrology and artificial recharge by spreading, and to create a conceptual model of what might be expected. The study area was then investigated to examine how closely the actual situation was reflected by the conceptual model, enabling recommendations to be made for the sound management of the system. The stormwater runoff component was found to differ from most urban hydrological studies as a result of its large baseflow component. The sandy nature of the catchment, small percentage area of effective impervious surface, and high groundwater table resulted in the baseflow constituting more than 40% of the total storm water runoff and accounting for over 60% of the pollution load. The "first flush" effect established as a major source of pollution in other studies, was found to be of minor significance in this study area. The overall stormwater quality (excluding the noxious industrial baseflow) was found acceptable for artificial recharge within the study area, although the baseflow from the industrial sub-catchments showed the potential for being a major source of pollution in the future. The treated wastewater used for artificial recharge prior to 1987 was found to be unacceptable for recharge purposes. The treated industrial effluent should under no circumstances be recharged up-gradient of the Witzand well field. The treated domestic effluent although of a poorer quality than the resident Witzand well field groundwater could be recharged in order to boost recharge volumes and form a buffer against further intrusion by the poor quality groundwater from the Brakkefontein area. This would however only be acceptable if strict water quality control is maintained and recharge does not take place west of the present basin. The recharge basin was found to be well situated with respect to influencing the Witzand wellfield and maintaining a groundwater buffer against poor quality groundwater flow from the northeast towards the central area of the wellfield. Unfortunately the surrounding low-lying topography and sandy retaining walls have resulted in return flow and raised groundwater-levels. The raised groundwater mound does not comply with the conceptual model and together with the sandy nature of the unsaturated zone resulted in less effective purification during infiltration. The practice of letting large portions of the basin floor dry-out during summer was shown to be beneficial and the periodic cleaning of the deeper portions of the basin essential. The artificially recharged water was found to have influenced the upper portion of the aquifer well beyond the West Coast Road. The study of groundwater quality being a good method for tracing artificially recharged water. The groundwater quality has improved as a result of artificial recharge since the removal of treated wastewater from the recharge basin. The groundwater was (ii) found to be very responsive to the slightest changes in recharge basin water quality or/and quantity. Management of the recharge basin therefore had to be very much of a compromise between qualitative and quantitative approaches. The present approach of recharging all the stormwater runoff throughout the year providing the most efficient compromise under the present conditions. The study revealed that the most efficient recharge management strategy would be the recharge of treated domestic sewage effluent in the present recharge basin and all residential storm water runoff plus industrial "storm flow" stormwater runoff in a new recharge basin located northwest of the present basin. Strict water quality control must be maintained on the water discharged into the basins and an annual wet/dry cycle implemented within the basins to boost infiltration. The entire system should continue being monitored to safe guard the groundwater resource from pollution and over exploitation.

This study assessed the effect of an application of mycorrhizal fungi to stormwater filter media on urban bioswale soil and stormwater in an infiltration-based bioswale aged 20 years with established vegetation. The study tested the use of commercially available general purpose biotic soil blend PermaMatrix ^® BSP Foundation as a treatment to enhance Earthlite™ stormwater filter media amelioration of zinc, copper, and phosphorus in an ecologically engineered structure designed to collect and infiltrate urban stormwater runoff before it entered the nearby Willamette River.

These results show that the application of PermaMatrix^® BSP Foundation biotic soil amendment to Earthlite™ stormwater filter media contributed to the reduction of extractable zinc in bioswale soil (-24% and -26%), as compared to the control, which received a treatment of Earthlite™ stormwater filter media only, and experienced an increase in extractable zinc levels (23% and 39%). The results presented also show evidence that after establishment mycorrhizal treatment demonstrated lowered levels of phosphorus in bioswale soil (-41%) and stormwater (-100%), in contrast to the control, which had increased phosphorus levels. The treatment contributed to reductions between 67% and 100% in every metric detected in stormwater after an establishment period of 17 weeks, while the bioswale with no mycorrhizal treatment had increases between 50% and 117%. Treatment also appeared to enhance the reduction of ammonium and nitrates, while contributing to a greater increase in soil pH.

Previous field demonstration projects in metro-Atlanta have shown that seep berms, which are elongated sedimentation basins at the outlet of a disturbed land area, can provide high suspended sediment trap efficiencies with respect to coarse sediments on construction sites having drainage areas greater than five acres. Previous literature has shown that vegetative filter strips are efficient traps for fine suspended sediment in stormwater runoff. A combination of a seep berm and vegetative filter in series was studied in this thesis as an erosion control measure with quantification of its flow resistance and sediment removal efficiency. First, a field demonstration project was implemented to evaluate seep berms as a viable erosion control measure through a side-by-side comparison with the more commonly-used silt fences on construction sites with drainage areas less than five acres in metro Atlanta. High suspended sediment trap efficiencies were recorded for the seep berm on two separate sites, and the seep berm was shown to be superior to silt fences with respect to sediment control in the site runoff. Then a vegetative filter was studied in the laboratory in a specially-built flume for that purpose. The relationship between vegetative drag coefficient and various parameters reflecting flow conditions and vegetation density in steady, uniform open channel flow was studied in the flume. Both rigid, emergent vegetation and submerged, flexible vegetation were studied at two different plant densities. The application of porous media flow concepts to open channel flow through vegetation resulted in a collapse of data for vegetative drag coefficient for the various vegetation types and densities into a single relationship when plotted against vegetative stem Reynolds number. Point velocity and turbulence intensity profiles at different locations in the vegetative filter were recorded with an acoustic Doppler velocimeter to observe the turbulence structure of the flow and its effects on vegetative drag and settling of sediment. A sediment slurry consisting of a suspension of fine sand was fed into the flume, and an automated sampler was used to measure suspended sediment concentrations along the vegetative filter length for a series of discharges from which sediment flux and trap efficiency could be determined. Experimental data for trap efficiency were plotted against a dimensionless settling efficiency for each type of vegetation and density. These relationships, along with the one developed for the coefficient of drag, were applied in a numerical design technique that allows designers to determine the flow depth, velocity and trap efficiency of a vegetative filter of known dimensions for a given flow rate, sediment grain size distribution, slope, and vegetation density. In a typical design example, the combined trap efficiency proved that a seep berm followed by a vegetative filter can be a very effective erosion control measure.

Bibliography :leaves 158-171. A monitoring program, funded by the South Australian government (through the former MFP Development Corporation), was established to monitor the quality and quantity of storm water entering and leaving the wetland. This study formed part of the funded program. Simple regression models were developed; and will assist in the monitoring of performance of the wetland to alleviate the pollutant load into the Barker Inlet.

Particles mobilized by stormwater negatively affect receiving surface waters. Stormwater best management practices (BMPs) can reduce solids along with associated pollutants in runoff but engineers and environmental managers have been long vexed by the problem of choosing the optimal BMP for a given situation. A common BMP process for solids removal is sedimentation. This thesis addresses the question of whether the effectiveness (and thus choice) of a sedimentation device can be estimated (and thus optimized) from the particle size properties of runoff, which, in turn, could be associated with specific runoff zones or land uses. Presented here is a series of experiments to determine the solids-removal capabilities of a manufactured oil-water separator that also removes solids via sedimentation. A statistical model developed from the experimental data shows that, under normal operating conditions, influent particle size can be used to accurately estimate effluent total suspended solids (TSS) for BMPs of this type. Relationships between particle size and particle-bound metal concentrations for Cu, Zn and Pb were then obtained from the literature and incorporated into the model to allow estimates of metal removal efficiencies based on TSS and PSD. The model can be used with an arbitrary particle size distribution (PSD); this allows effluent quality predictions to be made considering that particle sizes entering stormwater BMPs could vary due to anthropogenic, hydraulic or hydrologic factors. To place these experimental and modeling results in the context of an urban environment, samples of deposited stormwater solids were collected from residential areas, commercial areas and an industrial zone in Portland, Oregon, and the PSD of each sample was determined using light obstruction particle sizing. PSDs ranging over sizes from 3μm to 200μm vary among these locations. Areas with high anthropogenic impact were found to have PSDs skewed toward the smallest particle sizes. The statistical model developed here was then used to show that the effluent quality of the BMP tested would differ depending on the locations where solids were collected. The evidence presented in this thesis thus indicates that device performance will correlate with geographic locations or land use zone and validates further investigation into delineating the City of Portland's characteristic runoff zones and using the runoff characteristics of each zone to map it to the most desirable treatment practices.

Cities within California are beginning to incorporate urban agriculture into their land use designations. Prompted by residents and local organizations, cities are hoping to capture the benefits that urban agriculture provides. Research has shown that urban agriculture renews and beautifies neighborhoods, provides healthy food choices, increases public health, has the potential to help with stormwater runoff, creates jobs, and fosters community. In the last few years, several California cities have made headlines as they have adopted new zoning codes that include urban agriculture. In reviewing these new zoning codes and exploring the topic of urban agriculture, it became evident that just because an urban farm was small, organic and provided certain benefits that it was not free from impacting its surroundings. As more urban agricultural ventures are established within cities, planners have to carefully consider their effect. One such impact could be stormwater pollution. There is insufficient research to determine whether there is a relationship between urban agriculture and stormwater, however, studies on conventional agriculture and urban landscaping (mainly urban lawns) show that each of these areas pollute the local water bodies with sediment, chemicals, and nutrients. Is urban agriculture different? This thesis utilizes two case studies within California, the City of Oakland and the City of San Diego, to examine the similarities and differences between each city’s urban agriculture ordinances and evaluate whether or not the cities have adjusted stormwater requirements in parallel with these ordinances. Interview responses and site visits in each city were analyzed and compared to expound upon the approaches each city engaged. Using the collected data and analysis as a base, a set of guidelines was created for managing stormwater runoff from urban agriculture.

Thesis (Master of Community Planning)--University of Cincinnati, 2009.
Advisor: Xinhao Wang. Title from electronic thesis title page (viewed Feb. 22, 2010). Includes abstract. Keywords: Storm Water Runoff; Green Infrastructure; Addis Ababa; Urban Planning; Environmental Planning; GIS. Includes bibliographical references.

The HYDROPAC model was developed to improve the technology transfer from the science of hydrology to environmental planning disciplines by initiating advanced spatial analysis techniques for predicting rainfall-runoff relationships. This model integrates the Soil Conservation Service (SCS) equations for calculating runoff and a Geographic Information System (Map Analysis Package) in a framework that allows the simulation of runoff processes over a digital elevation model. The simulations are done in discrete time steps allowing the generation of a hydrograph at any desired point in the watershed and the overland flow patterns are displayed in maps. This framework addresses some of the current limitations of hydrologic model for stormwater management planning in terms of capabilities for analysis and communication of results. This manuscript describes the methods used to develop the framework of the HYDROPAC model and its usefulness for analyzing potential runoff problems during the planning process.

Urban runoff continues to impair water quality and there is an increasing need for stormwater management within the limited confines of urban spaces. We propose a system of structural soil and trees that can be incorporated beneath pavement. Structural soil has a high load-bearing capacity yet is engineered to support tree root growth. Stormwater is directed into a structural soil reservoir below the pavement where tree roots can also thrive.

Two container experiments evaluated tree function in this system. We examined whether tree roots can grow into compacted subsoils and if root penetration increases soil infiltration rate. Quercus velutina, Acer rubrum, and a no-tree variant were planted in 26.5 L (7 gal) containers and the rootballs surrounded by compacted clay loam. Roots grew into all layers of the compacted soil. Infiltration rate increased by 63% (+/-2%) compared to no-tree containers. A second experiment evaluated water uptake and tree development in fluctuating water tables. Quercus bicolor and Fraxinus pennsylvanica were planted in 94.6 L (25 gal) containers with structural soils (either Stalite or CU^® Structural Soil). Trees were subjected to fluctuating water tables simulating infiltration rates of 2, 1, and 0.1 cm/hr for two growing seasons.

Trees thrived in all infiltration regimes but roots were shallower in slowly drained treatments. Trees grew best and transpired the highest water volume with moderate infiltration. Even if trees uptake only small volumes of water, increased canopy size compared to conventional plantings (because of greater penetrable soil volume) allows greater rainfall interception thus decreasing runoff.

Master of Science

The environmental issues of storm water in the urban environment is addressed in political policies on many different governance levels. The concept of “sustainable storm water” in Europe uses the natural water cycle as a template for urban drainage, and the EU has a water framework directive (WFD) with a systems approach, using drainage basins as the starting point of all actions. In Stockholm, a new storm water strategy was adopted in 2015 with a sustainability approach, using much of the terminology from the WFD and the Swedish Water & Wastewater Association. To find new aspects related to sustainable development of storm water management in Stockholm, this study used a resilience framework of seven principles to analyse the implementation of the Stockholm storm water strategy (SSWS). A mixed method approach was used for a qualitative study, using interviews and a review of policy documentation as the main data sources, complemented by a desk study of literature on the subject of storm water management, as well as participation in some relevant workshops. To broaden the study, examples from a developing area within the Stockholm municipality, Stora Sköndal, was used, as well as another municipality in the Baltic Sea region; Helsinki (Finland). The SSWS leans on the legislation of the environmental quality standards (EQS) but is lacking in authority coordination on a national and municipal level in Stockholm. Diversity in problem formulations and solutions for infrastructure is high, so is the diversity of involved stakeholders, which is an indication of resilience. This in combination with the structure and communicational links having questionable functionality, leads to a complex and inefficient structure in management of storm water, which undermines the resilience of the system. However, since the SSWS and other connected policies (such as local programmes of measures and sustainability requirements) are new, the system is undergoing change, which shows some level of adaptability and complex adaptive systems (CAS) thinking, another resilience indicator. The implementation of the WFD on a municipal level is also connected to CAS thinking, as well as a polycentric governance system -one of the seven resilience principles of the framework used. Some of the main issues found within this study for building resilience in the SES are related to follow-up and responsibility division.
Miljöfrågor inom dagvatten hanteras i policyarbete på flera olika institutionella nivåer. Begreppet ”hållbart dagvatten” utgår i Europa från den naturliga vattencykeln och EU:s vattendirektiv (WFD) har en systeminriktning som utgår från avrinningsområden istället för andra geografiska gränsdragningar. Stockholms Stad antog en ny dagvattenstrategi 2015 med en hållbarhetsinriktning, som innehåller mycket terminologi från WFD och publikationer från branchorganisationen Svenskt Vatten AB. För att hitta nya aspekter för en hållbar utveckling av dagvattenhantering i Stockholm använder denna studie ett teoretiskt ramverk inom resiliens,, som bygger på sju principer, i en analys av stadens dagvattensstrategi (SSWS). Blandade metoder användes för att genomföra en kvalitativ studie, där policydokument granskades tillsammans med intervjuer av nyckelpersoner, vilket kompletterades med en skrivbordsstudie av litteratur om dagvattenhantering samt deltagande i relevanta workshops. För att bredda studien användes exempel från ett planprogramsområde inom Stockholms kommun, Stora Sköndal, liksom en annan kommun i Östersjöområdet; Helsingfors (Finland). SSWS bygger juridiskt på miljökvalitetsnormerna, men brister i myndighetssamordning på nationell och kommunal nivå i Stockholm. Problemformuleringar och infrastrukturlösningar har hög mångfald, precis som involverade aktörer, vilket är en indikation på att systemet bygger upp resiliens. Detta i kombination med att struktur och kommunikationslänkar är något bristfälliga leder till en komplex och ineffektiv dagvattenhantering, vilket underminerar resiliensen i systemet. Eftersom SSWS och andra relaterade styrdokument (t.ex. lokala åtgärdsprogram och hållbarhetskrav) är nya, genomgår systemet förändringar, vilket visar på anpassningsförmåga och komplext, adaptivt systemtänk (CAS), vilket är en ytterligare resiliensindikator. Implementeringen av WFD på kommunal nivå är också kopplad till CAS-tänkande, liksom ett polycentriskt styrsystem - en av de sju principerna för resiliens i det teoretiska ramverket som används. Några av de huvudsakliga problem för att bygga resiliens som hittades i denna studie är relaterade till uppföljning och ansvarsfördelning.

Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 17, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. Kathleen M. Trauth. Includes bibliographical references.

Monitoring of a regional stormwater management facility, located on the Virginia Tech campus in Blacksburg VA, was conducted in order to assess its efficacy in reducing nonpoint source pollutant losses downstream. The facility design includes both an upper water quality (wet) pond and a lower 100-yr-event quantity (dry) pond. These on-stream ponds capture both baseflow and storm runoff from the southern portion of the Virginia Tech campus and surrounding lands, and release the water back to the unnamed stream shortly above its conjunction with Stroubles Creek, a tributary of the New River. Monitoring sites for flow measurement, water quality sampling, and biotic assessments (habitat evaluation and rapid bioassessment of benthic macroinvertebrates) were located above and below each of the ponds.

Both grab samples and automated samples were collected at these stations. Between 1997 and 1999, water quality grab samples included 35 baseflow samples and 22 stormflow samples. The grab samples were analyzed for concentrations of total suspended solids (TSS), metals, bacteria, and nutrients as well as temperature, pH, dissolved oxygen, conductivity, total organic carbon (TOC), and chemical oxygen demand (COD). Automated flow-weighted sampling was initiated in February of 1999 and results are reported through the end of October 1999. Thirty-three storms in 1999 were monitored for flow and various water quality parameters (TSS, TOC, COD, and nutrients). Pollutant loads and pollutant removal estimates were calculated with regard to the wet pond, dry pond, and the combined facility. Two types of pollutant removal efficiencies were calculated: (1) the EMC efficiency, based on pollutant concentrations from individual storms; and (2) the SOL efficiency, based on pollutant loads, to estimate long-term performance over the study period. Benthic macroinvertebrate sampling and habitat assessment were performed in both 1997 and 1999. In addition, a preliminary investigation of pond characteristics was conducted, including measurements of water quality and composition, sediment deposition and composition, and residence time.

As a system, the stormwater management facility appears to have minimum impact on improving the downstream water quality. Pollutant concentrations and loads both appear to increase downstream of the facility as compared to upstream, during both storm event and baseflow periods. Monitoring results of the benthic assemblages showed evidence of moderate to high impairment at all sampling locations, and habitat assessments showed evidence of high sedimentation levels within the stream, even after installation of the stormwater management facility. Total suspended solids (TSS) concentration removal efficiency was 10% for the combined wet pond and dry pond system, much lower than the 80 to 90% TSS removal expected for properly functioning stormwater management facilities (Hartigan, 1989). There is some evidence of sedimentation within the ponds because of a slight reduction in sediment-bound constituent export, but the dissolved nutrient constituents had either very low and most often negative (indicating pollutant export) removal efficiencies. Concentrations of metals measured in the stream often exceeded their respective acute and chronic water quality criteria at all sampling locations.

Pollutant removal efficiencies measured in the wet pond are atypical of those reported in the literature (Schueler, 1993). Insufficient residence time (two days compared to the optimal two weeks), and wet pond embankment failure are likely the principal causes of the wet pond's inadequate performance and thus, the inadequate performance of the overall facility. TSS removal efficiencies were low in the wet pond (19% for concentrations and 33% for loads) compared to the 80 to 90% expected for similar ponds. Nevertheless, the wet pond reduced the concentrations of several pollutants typically associated with TSS and not likely to be associated with the fill material for the wet pond embankment. Zinc concentrations in sediment cores were highest near the pond inlet, where the majority of sedimentation occurs. During storm events, the following results were noted. Copper and zinc concentrations in 1998 were lower at the pond outlet as compared to the pond inlet, and TOC concentrations and loads were also reduced by the wet pond (13% for concentrations and 12% for loads). However, sedimentation is also expected to remove phosphorusl, and wet pond phosphorus loads were only reduced by 10% and 3% for orthophosphorus and total phosphorus, respectively.

Because the wet pond is undersized with respect to the watershed it serves (surface area less than 1% of the watershed area (0.87 ha), as compared to the 3% ratio often recommended for optimal pollutant removal (Athanas, 1988)), higher removal efficiencies were found during baseflow periods. The greatest reductions in baseflow concentrations were for ammonia (67%), nitrate (57%), total nitrogen (54%), and COD (45%). However, the residence time of two days appears to be insufficient to reduce fecal coliform concentrations in the stream, and over 40% of the fecal coliform samples collected exceeded the water quality standard for contact recreation (DEQ-WQS, 1997). Furthermore, the wet pond did not appear to reduce TSS or TOC during baseflow periods. Export of TSS (-29% EMC efficiency) and TOC (-44% EMC efficiency) from the wet pond during baseflow periods is likely due to the wet pond embankment failure as well as pond eutrophication. Eutrophication processes are favored by the water temperature increase as flow passes through the shallow wet pond. The wet pond increased downstream temperatures by approximately 8°C above inflow temperatures during the summer, and to levels above 21°C which cannot be tolerated by sensitive coldwater species (Schueler, 1987).

The dry pond did not remove dissolved nutrient constituents or other pollutants during baseflow periods, but there is some evidence of sedimentation within the dry pond during storm events. During storm events, the dry pond was effective in removing TSS, with a concentration removal efficiency of 69% (EMC efficiency) and loading removal efficiency of 43% (SOL Efficiency). Removal of TKN and total phosphorus (36% and 37% respectively for concentrations) within the dry pond is further evidence of sedimentation within the dry pond.

The wet pond embankment was built in 1997, and monitoring occurred during a potential stabilization period when evidence of water quality benefits are slow to appear, especially with respect to downstream habitat and aquatic communities. Some benefits which could have been observed more immediately may have been negated or masked by the progressive erosion of the wet pond embankment as a result of a design flaw. Further complicating the results is the appearance; based on observations of extended drawdown time and results from a water budget analysis in the wet pond (where inflow substantially exceeds inflow); that groundwater interacts with the pond in a complicated fashion, possibly including both recharge and discharge.

To fully understand the impact of the stormwater management facility on the water quantity and quality within this tributary of Stroubles Creek, monitoring efforts should continue after the wet pond embankment is repaired and is fully operational. If biotic community improvement is desired, the stabilization period could be defined by the time necessary to flush out accumulated sediment within the channel. Monitoring efforts should also expand to include the investigation of the groundwater regime and water level fluctuations within the wet pond. Further measurements of pollutant removal processes and influences upon those processes within the wet pond should also be considered. Last, the influence of the stormwater management facility on downstream flow regimes should be investigated to assess the adequacy of its performance with regard to flow control and prevention of stream channel degradation.
Master of Science

All land uses affect storm water runoff However, different uses of the same site generate varying amounts of runoff Many communities have come to rely upon detention and/or retention basins for controlling the additional runoff resulting from land development. It is argued that this incremental approach to storm water management must be replaced with a more proactive long-term view.To achieve this, more user-friendly software capable of modeling the effect long-range land use plans have on the volume and behavior of storm water runoff is needed. This software, called a Spatial Decision Support System (SDSS), must be capable of guiding the user, who may not be an expert at runoff analysis, through the process and also capable of generating output in various formats understandable by lay persons. This study utilizes a systems analysis technique to develop a theoretical framework for the Storm Water SDSS.
Department of Urban Planning

Khartoum State in Sudan is subject to the erratic and intense rainfall during the short rainy season and dryness and heat throughout the rest of the year. High intensity rainstorms with a short duration have become more frequent in the area during the last two decades resulting in cities inundation and flash floods in the rural parts. On the other hand, the dry season means hot weather in the urban parts and water shortage in the rural part. Rural areas are dependent on the runoff water brought about by the seasonal streams as a source of water. For this study, Khartoum City Center and Seleit area were taken to investigate the application of water harvesting in the urban and rural areas, respectively. Accordingly, the hydrological characteristics and the specification of the potential water harvesting sites and systems were examined. For Khartoum City Center, characteristics of the drainage system were examined using ArcGIS platform. It is found that the drainage system covers 42% of the area with total capacity of 24000 m3. Daily rainfall data for urban meteorological station were used to calculate the probability and the return period of the rainfall, as well as the potential runoff. Rainfall probability of occurrence was calculated applying Gumbel distribution method for extreme events that were arranged according to the Peak-over-Threshold method. The potential runoff that could be generated from a certain rainfall was calculated using the Natural Resources Conservation Services method provided by the United States Department of Agriculture (US-NRCS). Accordingly, the curve number was calculated depending on the land use/land cover and the hydrological soil group. Consequently, the weighted curve number is found to be 94%, indicating dominant imperviousness. 13.1 mm rainfall depth produces runoff volume equal to the drainage system capacity with return period of one year; whereas more than four folds the drainage system capacity is produced by 30 mm rainfall depth that is considered the threshold for raising flood hazard. Six potential sites for roof rainwater harvesting were selected. Accordingly, it is found that, the application of roof water harvesting in 18% and 72% of the commercial and business district buildings can accommodate the runoff resulting from the 13.1 and 30 mm rainfall depth, respectively. Hence, impounding rainstorm water would help managing the urban runoff water, and consequently, the stored water could be used for making more green areas that will enhance the urban environment. Three watersheds of ephemeral streams (wadi), namely Wadi El Kangar, Wadi El Seleit, and Wadi El Kabbashi make up Seleit area. Distinct maps were prepared in ArcMap for the calculation of the potential runoff and the specification of the appropriate water harvesting sites and systems. The Wadis watersheds areas are found to be 540, 344 and 42 km2 for Wadi El Kangar, Wadi El Seleit and Wadi El Kabbashi, respectively. Daily rainfall data of rural meteorological station were classified into three groups representing the soil dry (AMCI), moderate (AMCII), and wet (AMCIII) moisture conditions; the respective CNI, CNII, and CNIII values were calculated accordingly. The weighted CN values indicate high runoff potential within the three soil moisture conditions. Accordingly, the rainfall thresholds for runoff generation for AMCI, AMCII and AMCIII conditions are found to be respectively 18.3 mm, 9.1 mm and 4.4 mm for Wadi El Kabbashi and 22 mm, 11 mm and 5 mm for both Wadi El Seleit and Wadi El Kangar. El Kangar dam subwatershed was used for calibrating the potential runoff calculated by the NRCS method. Since the Wadis are ungauged, Google Earth and GIS platforms were used to calculate geometrically the volume of the dam reservoir water for three years. This volume was compared to the annual runoff calculated by the NRCS method. Consideration to different factors was made to locate the potential water harvesting sites. Accordingly, water harvesting systems for fodder and crop plantation; sand storage surface or subsurface dams; or groundwater recharge, were specified. The socio-economic study revealed that the financial capacity, if any, of the villagers is very limited. Thus, the financial source for the construction of the suggested potential water harvesting or the rehabilitation of the existing ones is questionable. Hence, other potential financial sources are needed to help executing water harvesting projects in the region, e.g. Khartoum State Government. Applying water harvesting in Seleit area is found to be promising. Improving the livelihood of the villagers by applying runoff water harvesting could assure better water accessibility, better income generation from farms production, and allocation of time for other activities, e.g. education. This would be reflected in reduced migration to nearby cities and stabilized market supply of agricultural and animal products. Therefore, the development of the rural part is of great benefit to the development of Khartoum State, as long as the interdependency and mutual benefit between the rural and urban areas, represented by the local food and labor market, remain exist.

Despite the technology advancement, degradation of water quality due to stormwater continues to be a significant threat to the water and ecosystems due to the exponential growth of industries and agricultural enterprises that discharge stormwater. These anthropogenic activities are the sources of high nitrogen and phosphorus quantities in stormwater, which is responsible for eutrophication phenomena and deterioration of public health. Floating Treatment Wetlands (FTWs) are a potential solution to this problem. Both microcosm and mesocosm level studies were conducted for the effective removal of nutrients in stormwater wet detention ponds with different sorption media under varying nutrient concentrations and weather conditions. Water depth, percent area coverage of the FTWs and littoral zone emergent plants were varied in order to determine nutrient removal efficiency before implementing in an actual pond. Focus has also been placed on the observations of macrophyte-epiphyte-phytoplankton interactions in order to understand temporal characteristics of ecological phenomena. Water quality parameters included Total Nitrogen, Total Phosphorus, Orthophosphate, Nitrate-Nitrogen, and Ammonia-Nitrogen in addition to in-situ parameters such as pH, Dissolved Oxygen, Temperature and Chlorophyll-a. Results clearly indicate that an FTW filled with sorption media of 80% expanded clay and 20% tire crumb can significantly promote the biomass growth. Different levels of nutrient concentrations did affect the plants' growth and cold temperature in late winter was detrimental to growth. To make the system more viable irrespective of the seasonal weather conditions, the adoption of mixed vegetation is highly recommended in the FTWs implementation.; It is also recommended that, the positioning of the floating wetlands should not be in the vicinity of the outlet of the pond as assimilated nutrient under the mat might increase the nutrient concentration in the discharged water. Finally, One-way ANOVA test is performed to check whether or not these grouped microcosms and mesocosms with differing experimental setup can be deemed statistically significant.
ID: 030422696; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.Env.E.)--University of Central Florida, 2011.; Includes bibliographical references (p. 70-74).
M.S.
Masters
Civil, Environmental and Construction Engineering
Engineering and Computer Science

This dissertation reports on the methods and results of a three-phased investigation to estimate the annual volume of ephemeral-channel-focused groundwater recharge attributable to urbanization (urban-enhanced groundwater recharge) in the Sierra Vista subwatershed of southeastern Arizona, USA. Results were used to assess a prior estimate.

The first research phase focused on establishment of a study area, installation of a distributed network of runoff gages, gaging for stage, and transforming 2008 stage data into time series of volumetric discharge, using the continuous slope-area method. Stage data were collected for water years 2008 - 2011.

The second research phase used 2008 distributed runoff data with NWS DOPPLER RADAR data to optimize a rainfall-runoff computational model, with the aim of identifying optimal site-specific distributed hydraulic conductivity values and model-predicted infiltration.

The third research phase used the period-of-record runoff stage data to identify study-area ephemeral flow characteristics and to estimate channel-bed infiltration of flow events. Design-storm modeling was used to identify study-area predevelopment ephemeral flow characteristics, given the same storm event. The difference between infiltration volumes calculated for the two cases was attributed to urbanization. Estimated evapotranspiration was abstracted and the final result was equated with study-area-scale urban-enhanced groundwater recharge. These results were scaled up to the Sierra Vista subwatershed: the urban-enhanced contribution to groundwater recharge is estimated to range between 3270 and 3635 cubic decameters (between 2650 and 2945 acre-feet) per year for the period of study. Evapotranspirational losses were developed from estimates made elsewhere in the subwatershed. This, and other sources of uncertainty in the estimates, are discussed and quantified if possible.

The study took place in Vietnam at Hanoi University of Science in the framework of the DAAD (German Academic Exchange Service) – “An advancement of the German-Vietnamese University partnerships”. The research has been supported by the program: “Wastewater and Solid Waste Management in Provincial Centers” and belongs to its technical component. The present diploma thesis elaborates the current situation of sewage sludge management in Vietnam and is dealing with sludge characteristics from both domestic sewage treatment facilities and septic tanks. During the research, different treatment components and treatment facilities have been analyzed to carry out a comprehensive survey of sewage sludge types. In this thesis, a guideline (draft) was developed as a main result, which can be helpful to bridge the legislative gap for sewage sludge re-use in Vietnam. In conclusion, an integrated concept has been developed, which recommends the application of selected proceeding elements to treat sewage sludge and the further utilization of re-useable materials in agriculture in a controlled and environmentally-safe manner
Die Diplomarbeit wurde im Rahmen des Deutsch-Vietnamesischem Auslandsaustauschprogramms an der „Hanoi University of Science“ verfasst. Dieses Vorhaben wurde unterstützt von dem DAAD (Deutschen Akademischen Austausch Dienst), und ist im technischem Bereich des Programms “Wastewater and Solid Waste Management in Provincial Centers“ einzugliedern. Die vorstehende Diplomarbeit beschäftigt sich mit dem aktuellen Klärschlammmanagement in Vietnam und liefert dabei detaillierte Resultate zu verschiedenen Klarschlammtypen aus kommunalen Abwasserbehandlungsanlagen. Bei den Untersuchungen wurden verschiedene Abwasser- und Klärschlammbehandlungsanlagen untersucht, um einen Überblick zu den gebräuchlichen Behandlungsmethoden in Vietnam zu erarbeiten. Zusätzlich wurden die institutionellen und rechtlichen Rahmenbedingungen überprüft. Der Entwurf einer Verordnung zur Verwertung von Klärschlamm in der Landwirtschaft wurde vorgelegt, um eine bestehende rechtliche Lücke in Vietnam zu schließen. Mit dieser Arbeit wurde ein integriertes Konzept entwickelt, welches mittels verschiedene verfahrenstechnische Elemente den Klärschlamm behandelt und darauffolgend das verwertbare Material in ausgewählten landwirtschaftlichen Flächen in einer kontrollierten und umweltschonenden Weise verwertet

Landfilling is the most common treatment of Municipal Solid Waste (MSW) in the An Giang province in south Vietnam. Many of the landfills are not sanitary and can be harmful to the environment and the residents, especially those who live within the settled distance limit of 1000 meters. There is a lack of knowledge about the people living close to landfills in the An Giang province. Therefore, the aim of the study was to investigate any issues about living close to landfills, by comparing health, knowledge and social issues, between people living near landfills and people in urban areas in the An Giang province. A total of 80 people was chosen in Long Xuyen and An Phu, for a questionnaire. The data was compiled and coded in Excel for further analyzation in SPSS. The results show differences in social issues, health and knowledge related to landfilling and solid waste. The experiences in the landfill areas could be taken in advantage. The study suggests using students in communication programs and workshops to increase knowledge and practice about solid waste among the citizens. To monitor landfills and the air in due to open burning of solid waste, is recommended.
Deponering är den vanligaste behandlingen av hushållsavfall i An Giang-provinsen i södra Vietnam. Många av dessa soptippar (deponier) är inte sanitära och kan vara skadliga för både miljön och invånarna som bor inom den bestämda avståndsgränsen på 1000 meter. Det finns brist på kunskap om de människor som bor nära deponier i An Giang-provinsen. Därför var syftet med studien att undersöka förekomsten av problem av att bo nära deponier i provinsen. Detta gjordes genom att jämföra hälsa, kunskap och sociala frågor mellan människor som bor intill deponier och människor i urbana områden. Totalt valdes 80 personer i Long Xuyen och An Phu till en enkätstudie. Uppgifterna sammanställdes och kodades i Excel för vidare analys i SPSS. Resultaten visade skillnader i sociala frågor, hälsa och kunskap relaterade till deponering och fast avfall. I deponiområdena fanns det mycket erfarenhet som skulle kunna utnyttjas. Studien föreslår bl.a. att använda skolungdomar i kommunikationskampanjer och workshops för att öka kunskap och praxis hos invånarna. Att övervakning och mäta deponier och luften p.g.a. öppen eldning av avfall, rekommenderas.

En el context de la transició cap a la sostenibilitat urbana un dels majors reptes que encaren les societats modernes és l’aprovisionament d'aigua, un recurs que és reconegut cada vegada més com a valuós mentre la quantitat i qualitat disponibles en disminueixen. La creixent evidència d'escassetat d'aigua a nivell mundial promou la necessitat de treballar en possibles sinèrgies entre les diferents fonts d’aigua existents i a diferents escales per tal de desenvolupar una xarxa més integrada, eficient i equitativa. Aquesta tesi es centra en l’aprofitament de l’aigua de pluja com a recurs endogen local amb el potencial per aconseguir un metabolisme més circular capaç de tancar els fluxos d'aigua i de complir amb els objectius d’autosuficiència hídrica en entorns urbans. Aquesta estratègia pot ajudar a reduir les infraestructures de captació i tractament necessàries per l'aigua potable, així com les de gestió i tractament d'aigües residuals, a la vegada que permet un major control del d’avingudes i inundacions en entorns urbans. No obstant actualment hi ha una manca de coneixement al voltant de quina és l’estratègia més adequada per a recollir aigües pluvials aplicable a cada escala urbana per una banda, i per l’altra la quantitat i qualitat del l’aigua d’escolament tampoc ha estat abordada en detall sota les condicions climàtiques i ambientals pròpies de les zones Mediterrànies (més concretament a Espanya). L'objectiu d'aquesta tesi és donar resposta a aquestes preguntes mitjançant el plantejament, l’avaluació i la validació del potencial i les avantatges de l’aprofitament d’aigües pluvials amb el menor impacte possible per tal d’assolir una millora en el cicle urbà de l’aigua en regions Mediterrànies. Per tal d'avaluar l'ecoeficiència de diverses estratègies de captació d'aigües pluvials en barris de nova construcció i determinar així l'estratègia òptima ambientalment, la infraestructures necessàries per la recollida, emmagatzematge i subministrament han estat dissenyades i avaluades des de la perspectiva de l’Anàlisi de Cicle de Vida (ACV). A més, diverses variables que afecten directament aquests sistemes han estat seleccionades i avaluades convenientment; entre elles s’inclou el model de densitat urbana, l'escala d’estudi , la ubicació del tanc dins de l'edifici, l'alçada d’aquest i per últim l’estratègia de subministrament d'aigua. Els resultats determinen l’impacte ambiental de cada escenari al llarg del cicle de vida de les infraestructures i indiquen l'opció ambientalment òptima per la recollida d'aigües pluvials a diferents escales. L'avaluació de la quantitat i qualitat potencial de d’aquest recurs en un entorn urbà s'ha desenvolupat per mitjà d'un estudi de cas experimental. Per a dur-lo a terme, set superfícies de captació diferents van ser seleccionats dins del campus de la UAB per cadascuna de les quals va ser adaptada una instal·lació de recollida i emmagatzematge de pluvials al llarg d’un període de 22 mesos de campanya experimental . La selecció de les diferents superfícies de captació es va realitzar d'acord amb dos criteris : el material de la superfície i el seu tipus d'ús . L'avaluació de la quantitat consistir en el càlcul dels models de regressió d'escolament - precipitació , l'estimació de la coeficient d’escolament (RC) global i l'abstracció inicial, mentre que les avaluacions de qualitat comprenen una varietat significativa dels paràmetres fisicoquímics i microbiològics. Els resultats van ser analitzats des d'un enfocament estadístic per validar la seva significança i correlació. Els criteris ambientals resultants d’aquesta tesi estan pensats per ajudar a definir les estratègies òptimes i determinar els usos de l'aigua de pluja amb els que millor s’aconsegueix la transició cap a la sostenibilitat de les zones urbanes, així com el redisseny més ecoeficient de les xarxes d'aigua urbana en el context del canvi climàtic. Aquests resultats poden servir d'orientació en la planificació i disseny urbà mitjançant la integració de criteris ambientals en els processos de presa de decisions.
In the context of transition towards urban sustainability one of the major challenges facing modern societies is the provision of water, a resource that is increasingly recognized as a valuable resource while the quantity and quality available is decreasing. The growing evidence of water scarcity worldwide enhance the need to work on synergies among the different existing water sources and urban scales in order to develop more integrated, efficient and equitable water networks. In this sense, this dissertation focuses on the use of rainwater as a local endogenous resources to achieve a more circular metabolism able to close water flows and capable of accomplish urban water self-sufficiency. This can help to reduce the collection and treatment infrastructure needs for drinking water as well as the management and treatment of wastewater while having a greater control of floods in urban environments. However, there is still a lack of knowledge on which is the most adequate rainwater harvesting (RWH) strategy for each urban scale on one hand, while on the other the quantity and quality of runoff has yet not been addressed under the local climatic and environmental conditions of Mediterranean areas (more specifically in Spain). The aim of this research was to answer this question by investigating, evaluating and validating the potential and advantages of using rainwater to achieve, with the lower impact possible, the improvement of the water cycle in urban areas located within the Mediterranean climate. In order to evaluate the eco-efficiency of several RWH strategies for newly built neighbourhoods and to determine the environmentally optimum strategy, the necessary rainwater collection, storage and distribution infrastructures were designed and then environmentally assessed through a Life Cycle Assessment (LCA) approach. In addition, several variables that directly affect RWH infrastructures were selected and conveniently assessed; these include the urban density model, the building scale, the tank location within the building, the building height and at last the water supplying strategy. The results evaluate the environmental performance of each scenario and indicate the most environmentally friendly option for rainwater harvesting at different scales. The assessment of the potential RWH quantity and quality in an urban environment was developed by means of an experimental case study. To develop it, seven different catchment surfaces were selected within the UAB campus for which an experimental RWH installation was adapted and run over a period of 22 months of experimental campaign. The selection of catchment areas was done according to two criteria: surface material and type of use of the surface. The quantity assessment consisted of the calculation of the runoff –rainfall regression models, the estimation of the global RC and of the initial abstraction, while quality assessments comprised a significant variety of physicochemical and microbiological parameters. From a statistical approach all results were tested for significance and correlated. The resulting environmental criteria are thought so to define the optimal strategies and uses of rainwater that best leads towards the sustainability of urban areas as well as the most eco-efficient redesign of urban water grids in the context of climate change. These results may provide useful guidance in urban planning and design by integrating environmental criteria into the decision-making processes.

Urbanization, often characterized by high impervious surface area, can result in excessive inputs of fine sediments into urban streams. Excessive fine sediments can blanket the stream bed filling the interstitial space in the substratum, which may have adverse effects on stream biota. A field survey was conducted in Oregon urban and non-urban basins to investigate the relationship between fine sediments and stream macroinvertebrates. Physical, chemical, and biological data were collected from 59 stream sites in two urban and two rural streams. The stream sites fulfilled a continuous sediment gradient, which ranged from a low of 2% of fine sediment in the substrate to a high of 64% with an average of 22%. The % fines, in Clear Creek (rural basin) was significantly lower than in the urban basins (Johnson Creek and Tryon Creek) (p=0.005). Johnson Creek (mean=23%) had approximately three times more fine sediment than Clear Creek (mean=7%), while Tryon Creek (mean=32%) had nearly five times as much fine sediment as Clear Creek. EPT taxa richness was significantly higher in both rural streams than in both urban streams (p0.05). For example, regression analysis of EPT taxa richness vs. % fine sediments displayed a coefficient of determination (r2) value of 0.2. Other macro invertebrates metrics displayed similar patterns. The lack of significant correlations may be due to the cumulative effect of basin-wide "historical land use past". Past land use activity may have resulted in long-term reductions of sensitive taxa in the basin taxa pool and efforts to improve local habitats may not be quickly colonized by pollution sensitive taxa. Long-term degradation to the urban streams resulted in a relatively homogenous assemblage of macro invertebrates, which may have confounded the quantitative relationship between sediments and macroinvertebrates. This study suggests there is a clear difference between urban and non-urban streams in terms of macro invertebrates, which may be likely due to sediments, but the quantitative relationship between fine sediments and macro invertebrates is weak.

Made available in DSpace on 2016-06-02T20:00:43Z (GMT). No. of bitstreams: 1 4369.pdf: 12366504 bytes, checksum: d0746d888c77116c1453db230bd4d8b3 (MD5) Previous issue date: 2012-05-03
Financiadora de Estudos e Projetos
The infiltration well as a Best Management Practices (BMPs) stands out because it requires small areas for its implementation an it´s fully applicable to urban lots. This paper presents an experimental study of an infiltration well built in real scale at Universidade Federal de São Carlos SP with the objective of evaluation its performance as a BMP in the control of stormwater runoff and the removal of suspension materials. The soil was characterized as sand loam, and infiltration capacity between 93,98 and 19,24 mm per hour, these values were obtained thought field tests by the inverted well method and the double ring infiltrometer method respectively. The Rain Envelope Method was used for sizing, and the well was intentionally sized at odds with the standards of safety project. With the electronic equipment s and the precipitation measures were monitored 22 real rain events and simulated rain events, during 11 months of the well operation. During this period there was no record of extravasation of the well, representing an efficiency of 100% in reducing the runoff. After eight months of the well operation tests were conducted about the permeability of the geotextile, and the amount of powder material in the aggregate materials content in the well, in other words, the gravel and sand making up the filter cover, and also the qualitative parameters: apparent color and turbidity. The geotextile showed permeability reductions of 50,7%, 7,7% and 21,2% in the samples from the background, the wall sides, and the cover of the well respectively. The well sand filter cover retained 34,8% of fines, while the gravel retained 0,13% for the same period. About the well efficiency analyses in the removing the parameters apparent color and turbidity, it was showed that it wasn t characterized as a treatment unit of these parameters, this fact is due to the quality of water which represents the roof inlet structure. For modeling the Puls method, the saturated soil permeability defined as K non optimized was calculated for each monitored event (Kno). Kno was adjusted by non-linear regression (K optimized - Ko) for each monitored event, restricting the parameters based on values obtained in the field tests, thus for each monitored rain event was obtained two moldings for the constant values of K (Kno and Ko). The model representativeness was evaluated by the coefficients of determination ranging from 0,68 to 0,98 for the events modeled with values from Ko and 0,02 to 0,76 for the Kno, being the Ko most representative for the modeling of Puls.
O poço de infiltração como técnica compensatória de drenagem, se destaca por necessitar de pequenas áreas para sua implantação e ser totalmente aplicável a lotes urbanos. Este trabalho apresenta um estudo experimental de um poço de infiltração construído em escala real no Campus da Universidade Federal de São Carlos SP com o objetivo de avaliar seu desempenho como estrutura compensatória de drenagem urbana no controle do escoamento superficial e na remoção de material em suspensão. O solo foi caracterizado como Areia Média Argilosa SC, com capacidade de infiltração entre 93,38 mm/h e 19,24 mm/h, valores obtidos em ensaios de campo pelos métodos de poço invertido e de duplo anel respectivamente. No dimensionamento utilizou-se o método da Curva Envelope e intencionalmente não seguiram-se as recomendações de segurança para projeto. Com auxílio de equipamentos eletrônicos e das medidas de precipitação, foram monitorados 22 eventos de chuvas reais e chuvas simuladas, durante 11 meses de funcionamento do poço. Neste período não houve registro de extravasamento do poço, representando uma eficiência de 100% na redução do volume escoado. Após oito meses de seu funcionamento foram realizados ensaios da permeabilidade do geotêxtil, do teor de materiais pulverulentos dos agregados ao poço, ou seja, a brita e a areia que compõem o filtro da tampa, e dos parâmetros qualitativos: cor aparente e turbidez. O geotêxtil apresentou redução média da permeabilidade de 50,7%, 7,7% e 21,2% nas amostras do fundo, paredes e tampa do poço respectivamente. A areia do filtro da tampa reteve 34,8% de finos, enquanto a brita reteve 0,13% de finos no mesmo período. Com relação á remoção da cor aparente e da turbidez constou-se que o poço não caracteriza-se como uma unidade de tratamento destes parâmetros, tal fato deve-se à qualidade da água do telhado que representa a entrada de água na estrutura. Para a modelagem pelo método de Puls a permeabilidade do solo saturado definida como K não otimizado (Kno) foi calculada para cada evento monitorado. O Kno foi ajustado através de regressão não-linear (K otimizado - Ko), restringindo os parâmetros com base nos valores obtidos nos ensaios de campo, dessa forma para cada evento monitorado obteve-se duas modelagens para os valores de K constantes (Kno e Ko). A representatividade do modelo foi avaliada por meio dos coeficientes de explicação que variaram de 0,68 a 0,98 para os eventos modelados com os valores de Ko, e de 0,02 a 0,76 para o Kno, sendo o Ko mais representativo para a modelagem de Puls.

As California contends with climate change and more extreme cycles of drought and deluge, water management agencies and conservation groups are looking towards solutions to the decreasing reliability of imported water supplies. Stormwater has historically been perceived as a threat to development but when captured properly, it presents a resource that can augment local water supplies. Solutions to water supply issues in California have traditionally employed technical and centrally controlled methods for importing water, but there is a growing understanding that parcel-level capture through vegetated swales presents an opportunity for reducing the impact that development has on California’s hydrology. Vegetated swales mimic nature’s effectiveness in reducing runoff speeds, removing pollutants and increasing groundwater supplies. No less a piece of California’s water infrastructure than canals and dams, these swales bring water infrastructure into the context of the California landscape. My report for the Chino Basin Water Conservation District analyzes the feasibility of installing vegetated swales in the Chino Basin region.

Thesis (M.Eng.Sc.)--University of Adelaide, Dept. of Civil and Environmental Engineering, 2000?
Corrigenda pasted onto front end-paper. The CD contains Excel spreadsheets containing data collected. Bibliography: leaves 209-222.