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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Legal Support for a Resilient Stormwater Management : Review of Swedish Regulations and Objectives

Aderklint, Denice January 2017 (has links)
Sustainability entails a system that has the capacity to sustain itself. Stormwater management is one part of the concept sustainable development but traditional practices entail adverse effects on social-ecological systems and there is a need for increasing the resilience of urban stormwater systems.  The growing pressure from climate change and intensified urbanization increase the need for stormwater management. If poorly managed the security and functioning of societies will be negatively affected. Regulations are essential in the achievement of sustainable urban environments. However, national regulations concerning stormwater management are spread through different legal frameworks from different times and it has been recognized that the spread could challenge implementation of the regulations and climate change adaptation. Administrative instruments are important to support the social, economic and ecological value of green and blue structures. The thesis target to analyze relevant regulations and investigate their effectiveness for a sustainable stormwater management through combined interpretation methods based on the intention behind the law and their function in society. The thesis claims that consequences of poorly regulated sustainable stormwater management results in an inefficient use of resources and pose a risk for the environment. Sustainable development is not visible in any article in the Law on General Water Services and it therefore risk to be overlooked in practice. The issues of urban stormwater need to be more integrated in the municipal work and planning processes. The analysis reveals that there is support for resilient stormwater management when there is a combination of up-to date research and an objective teleological interpretation. As the shift towards sustainable urban environments entails several aspects, the use of administrative instruments is one important strategy in ensuring urban resilience.
32

Riverfront remediation: redevelopment for human access and wildlife health

Swehla, Tyler January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Alpa Nawre / Historically, industrial riverfronts often polluted waters and sites with chemicals, leading to degraded ecosystem health and reduced numbers of aquatic wildlife downstream. These sites currently pollute the environment through residual chemicals and waste left behind by industrial-era production factories. Urban riverfront redevelopment offers many possibilities to restore wetland ecosystems and reestablish site connections to surroundings through human access. By redeveloping urban rivers for wetland protection and stormwater management, cities can begin to regain their connections with the landscape while providing resilient ecosystems through restoration. This proposal identifies possibilities for riverfront redevelopment as wetlands and tools for restorative action aiding increased human access and wildlife health. A stormwater management plan utilizing phytotechnology is proposed for the ARMCO Site at 7000 Winner Rd. Kansas City, MO, a former steel manufacturing site, adjacent to the Missouri River and Blue River waterways. Using plant material and landscape design, the ARMCO riverfront has been redesigned to unlock the full potential of treatment wetlands and showcase emerging treatment methods that could soon become typical cleanup procedure. A template for remediation design has been created with the techniques identified for remediation, stormwater treatment, and habitat creation outlined in the master plan proposal. Nine precedent studies have been used to identify key concepts for design phasing aimed at human accessibility and modifications of restorative tools. Careful deliberation of stormwater containment and flood plain levels define site layout while contributing design responses adaptable for year-round functionality coupled with landscape interest for each season. The techniques and planting palette have been tailored to address the specific site contaminants for the Missouri River riverfront but are adaptable for various contaminants and ecosystems.
33

Assessing Green Infrastructure Needs in Hampton Roads, Virginia and Identifying the Role of Virginia Cooperative Extension

Robinson, Daniel J. 08 August 2018 (has links)
The Hampton Roads region of southeast Virginia is largely defined by its abundant water resources. These water resources are also a source of unique issues for the region. Specifically, water quality challenges related to the Chesapeake Bay and recurrent flooding are the major concerns. Green infrastructure (GI) has emerged in recent years as an alternative to traditional stormwater conveyance and detention focused systems. GI practices focus on integrating infiltration, evapotranspiration, and other components of the water cycle into more conventional stormwater management systems. These systems provide several positive benefits, including local water quality and quantity control, community revitalization, and various public health benefits. In addition, GI implementation has seen strong levels of support from the Cooperative Extension System, with Extension faculty and staff around the U.S. supporting local municipalities through GI research, promotion, and program development. Despite widespread interest, GI has been slow to be adopted due to various barriers to its implementation. This study sought to identify the major barriers to the implementation of GI practices in Hampton Roads by conducting a needs assessment. Municipal stormwater staff were invited to participate in an online survey aimed at identifying the most significant barriers in the region. At the same time, local staff with Virginia Cooperative Extension (VCE) were interviewed to explore their potential to become involved in promoting GI adoption in Hampton Roads. Survey respondents and interview participants found common ground in identifying costs, funding, and maintenance issues as the most significant barriers to GI implementation in Hampton Roads. In addition, VCE staff were found to be well suited to support widespread GI adoption in the region, having familiarity with the GI concept and access to unique resources in the form of knowledgeable Master Gardener volunteers and connections to Virginia Tech. Recommendations for VCE involvement in promoting GI in Hampton Roads include conducting cost studies, developing and hosting maintenance training programs, and taking advantage of partnerships to identify and obtain funding from diverse sources. By focusing on these widely acknowledged challenges at the regional scale, VCE can support GI implementation throughout all of Hampton Roads. / Master of Science / Hampton Roads is a region with a history and economy tied to its local waters. Today, the region is facing significant challenges related to these waters, including frequent flooding impacts on residents and pollution control needs for the nearby Chesapeake Bay. Green infrastructure (GI), a relatively new approach to managing water in cities, could help local governments address these challenges. Virginia Cooperative Extension (VCE), an organization formed through a partnership between federal and local governments and land grant universities in Virginia, seeks to meet community needs through community outreach and educational programs. As a community-centered organization with a history of advancing environmental education, VCE may also be an important partner for municipalities in Hampton Roads interested in adopting GI practices. To identify the barriers to GI in Hampton Roads and the potential role of VCE in addressing them, a needs assessment of municipalities in the region with stormwater permits was conducted. Based collected documents, surveys of municipal staff, and interviews with VCE personnel, three major barriers to GI adoption were identified. Permitted municipalities in Hampton Roads are uncertain of GI costs, have limited funds to support GI practices, and lack the knowledge and resources needed to maintain GI practices over time. VCE can help municipalities address these challenges using its many resources. Through its connection to Virginia Tech and Virginia State University, VCE can help in developing cost research studies for Hampton Roads. As an educational organization, VCE can also help municipalities win funding for GI projects that they would otherwise not have access to. Finally, local Virginia Tech faculty at the Hampton Roads Agricultural Research and Extension Center and experienced Master Gardener volunteers can work to develop GI maintenance training resources for maintenance staff throughout the region. With its strong background, expert knowledge, and existing connections in the region, VCE can play an important role in addressing the GI adoption challenges in Hampton Roads.
34

Shade, Moisture, and Woody Vegetation in Stormwater Management Basins: Influence on Cattail (Typha spp.) Growth

Bocskor, Priscilla 13 May 2010 (has links)
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
35

Applying the RUSLE and SEDD Equations to an Agricultural Watershed in Southwest Virginia - A Case Study in Sediment Yield Estimation Using GIS

Lally, Lindsay Backus 12 June 2013 (has links)
The goal of this study is to develop a model using GIS to estimate the source and quantity of accumulated sediment in the Emory & Henry College (EHC) duck pond.  Located in the Highlands of Southwest Virginia, the 1,194 acre duck pond watershed consists primarily of agricultural, forested, and low density urban land uses. The Revised Universal Soil Loss Equation (RUSLE) and the Sediment Distributed Delivery (SEDD) prediction models were used to determine the quantity of eroded sediment and the sediment yield at the duck pond, respectively.  These models require numerous computations, which were performed at the watershed scale with the aid of ArcGIS software.  In ArcGIS the watershed was broken into a raster grid of approximately 5,200 discrete 100 foot by 100 foot grid cells. The resulting watershed erosion model identified two main sources of sediment: a cluster of farms relatively close to and east of the duck pond, and a harvested timber site north of the duck pond.  The model predicted that 1,076 tons of sediment are delivered into the duck pond annually. The estimated sediment yield was then compared to the estimated amount deposited between October 2011 and September 2012, as measured by a topographic survey.  The model prediction was found to be within a factor of 6.3x of the measured value.  The predicted and measured sediment yields as well as identified erosion sources can be used to develop a water quality improvement plan and to help alleviate the need for periodic dredging. / Master of Science
36

The Effect of Slope and Media Depth on Growth Performance of Sedum Species in a Green Roof System in Mississippi's Sub-Tropical Climate

Kordon, Sinan 11 August 2012 (has links)
In recent years, green roofs have become an accepted solution in ecological urban design to mitigate the impacts of impervious surfaces (Berghage, Beattie, Jarrett, Thuring, & Razaei, 2009). An experimental research project was conducted at the Mississippi Agriculture and Forestry Experiment Station (MAFES) Green Infrastructure Research Area at South Farm of Mississippi State University to determine how medium depth and slope gradient on rooftops affect plant cover and survival. Plant cover was monitored monthly by photographing the experimental green roof platforms. Photoshop and AutoCAD software programs were employed to digitize and to calculate plant cover from the images. All recorded data was analyzed with Analysis of Variance (ANOVA) tests. It was determined that the effects of medium depth and slope are statistically significant on plant cover and survival.
37

Evaluation of the efficacy of different best management practices under current and future climate regimes in Ludlow watershed

Fan, Rong 16 October 2015 (has links)
No description available.
38

Urban Watershed Characterization: Dry Run Columbus, Ohio

Liu, Guangdong 29 August 2012 (has links)
No description available.
39

Engineered biochar and EAF slag for the removal of phosphorus from stormwater runoff

Johnson, James Casey 25 November 2020 (has links)
Phosphorus (P) in stormwater runoff has detrimental effects on water quality and ecosystem health when it reaches surface waters and promotes algal blooms. Constructed wetlands (CWs) have been utilized to combat this problem by containing stormwater and removing excess nutrients. Including filter materials in the design of CWs has shown promise for increasing their capacity for nutrient removal. This mesocosm scale study was conducted outdoors over a 12-month period to evaluate the effectiveness of three filter materials in their ability to adsorb phosphorus, retain water, and support plant life. The filter materials examined were electric arc furnace (EAF) slag, engineered biochar, and sand. All treatments demonstrated positive plant response and the ability to retain water. The EAF slag and biochar removed significant amounts of P from effluent and appear to be suitable materials for integrating into CW design. Sand was found to be ineffective as a P filter.
40

Rainwater harvesting: An assessment of the future potential in Sweden. / Regnvattenåteranvändning: En utverdering av framtida potential i Sverige.

Jensen Wennberg, Anton January 2018 (has links)
The thesis address the field of stormwater management. With a changing climate, the field of stormwater management much like many other fields will need to incorporate sustainable development if overall sustainability is to be reached. The aim of the thesis is to evaluate the current method for dealing with stormwater in Sweden, mainly in urban areas, and point to issues at hand and identified ways of addressing them. The concept of Rainwater Harvesting (RWH) is assessed. A comparison of results from several case studies from around the world show that there are several aspects of high importance for the viability of such technology. Among others price for municipal water, ability to lower costs due to smart planning ahead of installing, inclusion of environmental aspects and impacts on society such as reduced load on water, wastewater and stormwater infrastructure, reduced pollution load and greenhouse gas emissions (mainly due to less water treated at wastewater treatment facilities). The main conclusion from comparing and compiling results were that the viability of RWH from an economic standpoint is questionable. Although if including all identified gains for the municipality including stormwater management benefits and indirect gains due to reduced load and taking all aspects of importance into consideration there is potential for such technology even in a country like Sweden with good water supply and infrastructure in place. This thesis is of importance since it brings RWH technology into the light as a potential sustainability measure in Sweden. It evaluates the important parameters for the technology to be viable as indicated by case studies and literature within the field. / Detta examensarbete behandlar hållbar dagvattenhantering och specifikt tekniken Rainwater harvesting. Nuvarande centrala system för att förse Stockholm med färskvatten samt hantera bildat dagvatten utvärderas i en litteraturstudie. Även identifierade metoder för att hantera dagvattnet i linje med hållbarhetsmål beskrivs. Tekniken Rainwater harvesting beskrivs, dess historia samt implementering i moderna sammanhang framställs. Flertalet fallstudier där tekniken beskrivs analyseras och jämförs. Detta examensarbete är av vikt eftersom det tar upp tekniken RWH i relation till Sverige som potentiellt lokalt system för att uppnå hållbarhet. Det utvärderar viktiga parametrar för att tekniken ska anses försvarbar vilka indikeras av flertalet fallstudier samt litteratur. Dagens system för hantering av dagvatten i Stockholm består till allra största grad av det centrala avloppssystemet bestående av kombinerat samt duplikat avloppsnät. Detta har likt många centrala infrastruktursystem nackdelen att det är kostsamt och besvärligt att uppdatera och stärka, men dessutom flertalet nackdelar relaterade till miljöpåverkan och hög belastning på reningsverk. Rainwater harvesting är en teknik med lång historia som i moderna samhällen implementeras i syfte att minska vattenanvändningen samt belastningen på centralt dagvattensystem. Blandade ekonomiska resultat har observerats, sannolikt på grund av varierande analysmetoder och varierande inkludering av viktiga parametrar i bedömningar. Miljönyttan är till viss del tydlig, dock i många fall ej medtagen i beräkningar och utvärderingar. Analys av fallstudier påvisar hög potential för tekniken vid smart implementering men att det även finns goda exempel på system som resulterat i mycket dåliga ekonomiska resultat. Flertalet viktiga aspekter att ta hänsyn till för att uppnå försvarbara resultat har identifierats och beskrivits. Huvudslutsatsen är att Rainwater harvesting i och med sin potential att nå eller jobba mot definierade mål för dagvattenhantering och hållbar utveckling bör has med i åtanke som potentiellt lokalt system i Sverige kommande år.

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