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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.
181

Cumulative Impacts of Stream Restoration on Watershed-Scale Flood Attenuation, Floodplain Inundation, and Nitrate Removal

Goodman, Lucas M. 01 1900 (has links)
Severe flooding and excess nutrient pollution, exacerbated by heightened anthropogenic pressures (e.g., climate change, urbanization, land use change, unsustainable agricultural practices), have been detrimental to riverine systems and their estuaries. The degradation of riverine systems can negatively impact human and environmental health, as well as local, regional, and even global economies. Floods provide beneficial ecosystem services (e.g., processing pollutants, transferring nutrients and sediment, supporting biodiversity), but they can also damage infrastructure and result in the loss of human life. Meanwhile, eutrophication can cause anoxic dead zones, harming aquatic ecosystems and public health. To address the issues facing riverine systems, focus has shifted to watershed-scale management plans. However, it can prove challenging to quantify the cumulative impacts of multiple stream restoration projects within a single watershed on flooding and nutrient removal. Previous studies have quantified the effects of stream restoration on flood attenuation. However, our first study fills a substantial knowledge gap by evaluating the impacts of different floodplain restoration practices, varied by location and length, on flood attenuation and floodplain inundation dynamics at the watershed scale during more frequent storm recurrence intervals (i.e., 2-year, 1-year, 0.5-year, and monthly). We created a 1D HEC-RAS model to simulate the effects of Stage 0 restoration within a 4th-order generic watershed based on the Chesapeake Bay watershed. By varying the percent river length restored and location, we found that Stage 0 restoration, especially in 2nd-order rivers, can be particularly effective at enhancing flood attenuation and floodplain inundation locally and farther downstream. We addressed the water quality component by using a random forest machine learning approach coupled with artificial neural networks to find trends and predict nitrate removal rates associated with spatial, temporal, hydrologic, and restoration features. Our results showed that hydrologic conditions were the most important variable for predicting actual nitrate removal rates. Overall, both studies demonstrate the importance of hydrologic connectivity for flood attenuation, channel-floodplain exchange, and nutrient processing. / Maryland Department of Natural Resources; National Fish and Wildlife Foundation through the U.S. Environmental Protection Agency’s Chesapeake Bay Program Office; Chesapeake Bay Trust / Master of Science / Severe flooding and nutrient pollution from sources such as urban and agricultural runoff have been detrimental to the health of rivers. The degradation of rivers can negatively impact human and environmental health, as well as local, regional, and even global economies. Floods can be both helpful, by providing water quality benefits and supporting wildlife, and harmful, causing damage and even loss of life. Excess nutrients, such as nitrogen, can create underwater zones void of life, with serious consequences for aquatic life and public health. To address the flooding and water quality issues facing rivers, focus has shifted to landscapelevel river network management plans. However, it can prove challenging to understand the impacts of multiple stream restoration projects within a larger river network on flooding and nutrient removal. We address the flooding component by using a model to simulate the effects of different floodplain restoration techniques on a medium-sized watershed that is generally based on streams that flow into the Chesapeake Bay. Our model simulated small, relatively frequent storm events that, on average, occur every two years to once a month. By varying restoration length and location, we found that restoration practices with lower streambanks can be particularly effective at slowing down floods, reducing their overall severity by allowing more water to access the floodplains. This was especially true when restoration occurred in smaller streams, and the effects were seen both locally and farther downstream. We address the water quality component by using a different model to find patterns and predict nutrient removal rates associated with different landscape, seasonal, storm event, and restoration features. Our results showed that the most important variable for predicting nutrient removal rates was whether a stream was experiencing normal flow or stormflow conditions. Overall, both studies demonstrate the importance of restoring rivers in a manner that encourages water to flow from the channel into the floodplains during smaller storm events, because this will reduce the severity of downstream flooding while simultaneously improving water quality.
182

Will we need to change the rules : assessing the implications of climate change for dam operations in Oregon's McKenzie River Basin

Danner, Allison G. 21 March 2013 (has links)
Dams and reservoirs are important components of water resource management systems, but their operational sensitivity to streamflow variability may make them vulnerable to climate change. Climate change is likely to affect the magnitude and timing of streamflow, motivating the assessment of potential impacts on dams and reservoirs. Here I examine a case study of Cougar Dam, a multipurpose dam in Oregon, USA, to assess potential impacts of future climate change on operational performance. In the first portion of this study, I examine the historical operation of Cougar Dam, to understand (1), whether operational objectives have been achievable in the past despite operational variability, and (2) how climatic variation is expressed in operational trajectories. By analyzing historical streamflow and operations data using a set of metrics, I characterize variability in past operations and how that variability relates to streamflow. I also employ a reservoir model to distinguish operational differences due to streamflow variability from variability due to other factors that affect operations. I find that operational objectives have been achievable, despite variability in operations and departures from the ideal operational trajectory. Throughout the historical period, flood control operations have almost always kept reservoir outflows below the desired maximum outflow. Although filling occurs 9 days late on average, the reservoir has filled in all but 6 out of 37 years. Although drawdown occurs 47 days early on average, early drawdown does not generally impact recreation and allows minimum outflows to be met every day during all but the driest year. I also find that total seasonal inflow is correlated with measures of operational performance, and that other factors besides climate play an important role in determining operational trajectories. I conclude that operations of Cougar Reservoir are vulnerable to climate change, but that operational flexibility may mitigate some of the potential impacts. In the second portion of this study I assume that current operating rules will be kept in place and I aim to understand what types of operational impacts may be expected, when they may be expected to occur, and whether the operational impacts may necessitate changing operational rules. I employ both a traditional climate impacts assessment approach to assess changes over time as well as a scenario-neutral approach to generalize relationships between streamflow and operations of Cougar Dam. I find that projected increases in winter streamflow could result in up to twice the number of downstream high flows than in the past and that projected decreases in summer streamflow could result in earlier reservoir drawdown by up to 20 days on average. Additionally, filling of the reservoir may occur up to 16% more often or 11% less often than in the past, depending on spring flow magnitude and timing. I also find that there are strong general relationships between total inflow volume and flood control performance, and that there are total inflow thresholds for whether or not the reservoir will fill or will be full enough for recreation in late summer. I conclude that future modification of operating policies may be warranted, but that there will likely be tradeoffs between operating objectives in the future even if operating rules are modified. / Graduation date: 2013
183

Investigating Rainwater Harvesting as a Stormwater Best Management Practice and as a Function of Irrigation Water Use

Shannak, Sa'D Abdel-Halim 2010 December 1900 (has links)
Stormwater runoff has negative impacts on water resources, human health and environment. In this research the effectiveness of Rain Water Harvesting (RWH) systems is examined as a stormwater Best Management Practice (BMP). Time-based, evapotranspiration-based, and soil moisture-based irrigation scheduling methods in conjunction with RWH and a control site without RWH were simulated to determine the effect of RWH as a BMP on a single-family residence scale. The effects of each irrigation scheduling method on minimizing water runoff leaving the plots and potable water input for irrigation were compared. The scenario that reflects urban development was simulated and compared to other RWH-irrigation scheduling systems by a control treatment without a RWH component. Four soil types (sand, sandy loam, loamy sand, silty clay) and four cistern sizes (208L, 416L, 624L, 833L) were evaluated in the urban development scenario. To achieve the purpose of this study; a model was developed to simulate daily water balance for the three treatments. Irrigation volumes and water runoff were compared for four soil types and four cistern sizes. Comparisons between total volumes of water runoff were estimated by utilizing different soil types, while comparisons between total potable water used for irrigation were estimated by utilizing different irrigation scheduling methods. This research showed that both Curve Number method and Mass-Balance method resulted in the greatest volumes of water runoff predicted for Silty Clay soil and the least volumes of water runoff predicted for Sand soil. Moreover, increasing cistern sizes resulted in reducing total water runoff and potable water used for irrigation, although not at a statistically significant level. Control treatment that does not utilize a cistern had the greatest volumes of predicted supplemental water among all soil types utilized, while Soil Moisture-based treatment on average had the least volume of predicted supplemental water.
184

Some Legal Problems of Urban Runoff

Holub, Hugh 06 May 1972 (has links)
From the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona / Pressure is being brought to bear on national resources of air, earth, and water in the growing cities in the arid southwest. Legal questions involved in capturing urban runoff and putting it to a beneficial use are examined. Urbanization of a watershed results in a 3 to 5 fold increase in runoff amounts. Legal aspects include tort liability from floods, water rights to the increased flows, land use restrictions along banks and flood plains, condemnation of land for park development and flowage easements, financing problems, zoning applications, and coordination of governmental bodies responsible for parks, storm drainage and related services. Urban runoff is the most obvious legal problem in the tort liability area. It appears feasible to divert small quantities of water from urban wastes for recreational uses which provide flood control benefits. It appears that municipalities could appropriate increased flows caused by urbanization. The ultimate legal questions remain to be resolved by legislation, litigation or extension of the appropriative system.
185

An adaptation of the SCS-ACRU hydrograph generating technique for application in Eritrea.

Ghile, Yonas Beyene. January 2004 (has links)
Many techniques have been developed over the years in first world countries for the estimation of flood hydrographs from small catchments for application in design, management and operations of water related issues. However, relatively little attention has been directed towards the transfer and adaptation of such techniques to developing countries in which major hydrological decisions are crucially needed, but in which a scarcity of quality hydrological data often occurs. As a result, hydrologists and engineers in developing countries are frequently unable to alleviate the problems that extreme rainfall events can create through destructive flood flows or, alternatively, they do not possess the appropriate tools with which to design economically viable hydraulic structures. Eritrea is a typical example of a developing country which faces difficulties in regard to the adaptation of an appropriate design flood estimation technique for application on small catchments. As a result, the need has arisen to adapt a relatively simple and robust design flood model that can aid hydrologists and engineers in making economic and safe designs of hydraulic structures in small catchments. One objective of this study was, therefore, to review approaches to hydrological modelling and design flood estimation techniques on small catchments, in order to identify the barriers regarding their adaptation, as well as to assist in the selection of an appropriate technique for application, in Eritrea. The southern African adaptation of the SCS (i.e. Soil Conservation Service) design hydrograph technique, which has become a standard method for design flood estimation from small catchments in that region, was selected for application on small catchments in Eritrea for several reasons. It relies on the determination of a simple catchment response index in the form of an initial Curve Number (CN), which reflects both the abstraction characteristics and the non-linear stormflow responses of the catchment from a discrete rainfall event. Many studies on the use of SCS-based hydrological models have identified that adjustment of the initial CN to a catchment's antecedent soil moisture (ASM) to be crucial, as the ASM has been found to be one of the most sensitive parameters for accurate estimates of design flood volumes and peak discharges. In hydrologically heterogeneous regions like Eritrea, the hypothesis was postulated that simulations using a suitable soil water budgeting procedure for CN adjustment would lead to improved estimates of design flood volumes and peak discharges when compared with adjustments using the conventional SCS antecedent moisture conditions (SCS-AMC) method. The primary objective of this dissertation was to develop a surrogate methodology for the soil water budgeting procedure of CN adjustment, because any direct applications of soil water budgeting techniques are impractical in most parts of Eritrea owing to a scarcity of adequate and quality controlled hydrological information. It was furthermore hypothesised that within reasonably similar climatic regions, median changes in soil moisture storage from the socalled "initial" catchment soil moisture conditions, i.e. LIS, were likely to be similar, while between different climatic regions median LISs were likely to be different. Additionally, it was postulated that climatic regions may be represented by a standard climate classification system. Based on the above hypotheses, the Koppen climate classification, which can be derived from mean monthly rainfall and temperature information, was first applied to the 712 relatively homogeneous hydrological response zones which had previously been identified in southern Africa. A high degree of homogeneity of median values of LIS, derived by the daily time step ACRU soil moisture budgeting model, was observed for zones occurring within each individual Koppen climate class (KCC) - this after a homogeneity test had been performed to check if zones falling in a specific KCC had similar values of median LIS. Further assessment within each KCC found in southern Africa then showed that a strong relationship existed between LIS and Mean Annual Precipitation (MAP). This relationship was, however, different between KCCs. By developing regression equations, good simulations of median LIS from MAP were observed in each KCC, illustrating the potential application of the Koppen climate classification system as an indicator of regional median LIS, when only very basic monthly climatological information is available. The next critical task undertaken was to test whether the estimate of median LIS from MAP by regression equation for a specific Koppen climate class identified in southern Africa would remain similar for an identical Koppen climatic region in Eritrea. As already mentioned, LIS may be determined from daily time step hydrological soil moisture budget models such as ACRU model. The performance of the ACRU stormflow modelling approach was, therefore, first verified on an Eritrean gauged research catchment, viz. the Afdeyu, in order to have confidence in the use of values of LIS generated by it. A SCS-ACRU stormflow modelling approach was then tested on the same catchment by using the new approach of CN adjustment, termed the ACRU-Koppen method, and results were compared against stormflow volumes obtained using the SCS-AMC classes and the Hawkins' soil water budgeting procedures for CN adjustment, as well as when CNs remain unadjusted. Despite the relatively limited level of information on climate, soils and land use for the Afdeyu research catchment, the ACRU model simulated both daily and monthly flows well. By comparing the outputs generated from the SCS model when using the different methods of CN adjustment, the ACRU-Koppen method displayed better levels of performances than either of the other two SCS-based methods. A further statistical comparison was made among the ACRU, the SCS adjusted by ACRU-Koppen, the SCS adjusted by AMC classes and the unadjusted SCS models for the five highest stormflows produced from the five highest daily rainfall amounts of each year on the Afdeyu catchment. The ACRU model produced highly acceptable statistics from stormflow simulations on the Afdeyu catchment when compared to the SCS-based estimates. In comparing results from the ACRU-Koppen method to those from the SCS-AMC and unadjusted CN methods it was found that, statistically, the ACRU-Koppen performed much better than either of the other two SCS based methods. On the strength of these results the following conclusions were drawn: • Changes in soil moisture storage from so-called "initial" catchment soil moisture conditions, i.e. L1S, are similar in similar climatic regions; and • Using the ACRU-Koppen method ofCN adjustment, the SCS-SA model can, therefore, be adapted for application in Eritrea, for which Koppen climates can be produced from monthly rainfall and temperature maps. Finally, future research needs for improvements in the SCS-ACRU-Koppen (SAK) approach in light of data availability and the estimation ofL1S were identified. From the findings of this research and South African experiences, a first version of a "SCSEritrea" user manual based on the SAK modelling approach has been produced to facilitate its use throughout Eritrea. This user manual, although not an integral part of this dissertation, is presented in its entirety as an Appendix. A first Version of the SCS-Eritrea software is also included. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.
186

Urbanistické řešení nábřeží řeky Jihlavy v Třebíči / Urban design of waterfront in Třebíč

Vacek, Jiří January 2014 (has links)
Thesis is concerning urbanistic treatment of Jihlava river embankment in the city of Třebíč. Tries to find cause for urban non-functionality of the area within local and wider context to its surroundings. Offers possible solution for rehabilitation of the urbanistic function of the embankment, including putting the embankment into role of important passageway, improving its bounds to the surroundings and active role in city's everyday life.
187

Investigating prospects of integrating spatial planning with disaster risk reduction in flood prone settlements of Greater Tzaneen Municipality of Limpopo Province in South Africa

Tladi, Mazwi Thapelo 18 May 2019 (has links)
MURP / Department of Urban and Regional Planning / Disaster is posing serious threats to both human lives, infrastructure and the environment at large. Greater Tzaneen Municipality (GTM) is one of the many municipalities that suffer from flood related disasters. Lack of integration between Disaster Risk Reduction (DRR) and spatial planning has compounded the disaster risk situation in the municipality. This study sought to investigate the prospects of integrating spatial planning with disaster risk reduction in flood prone areas of GTM. The study is guided by three research objectives. First, the study sought to analyse spatial planning attributes that can be valorised for DRR in flood prone areas; Secondly, it sought to analyse spatial planning factors that define vulnerability attributes of households occupying flood prone areas. Finally, the study sought to perform a cluster analytical creation of a typology of households whose resilience to flooding could be enhanced through spatial planning. Twenty-five flood prone areas were analysed on the basis of four main flood vulnerability attributes. In order to identify such vulnerability attributes, the study borrowed critical insights from literatures on flood vulnerability, spatial planning and DRR. Such a critical review of literature was complemented by the use of pattern matching as a qualitative research instrument. Quantitative that was gathered using a structured observation checklist. Quantitative data generated was first subjected to various statistical tests that included Normality and Reliability Tests. Common measures of Normality test used included measures of skewness, kurtosis and the use of Normal Q-Q plots. To assess flood vulnerability, Hierarchical Cluster Analysis (HCA) was used. HCA was used to identify clusters of flood prone areas which had common characteristics in terms of the four main study constructs proposed by the study which included the physical/engineering, socio-economic, ecological/natural and political or governance conditions characterizing each area. HCA was then used to identify main clusters exhibiting similar characteristics and the associated level of vulnerability of such of communities occupying such clusters. Study results revealed 2 main clusters of flood prone areas whose differences lay in interactions that existed between the physical/engineering, socio-economic, ecological/natural and political or governance conditions characterizing each area. Such clusters depicted 2 levels of vulnerability that is high, and moderate. A number of opportunities and constraints were generated using the SWOT matrix strategy with the main results showing that spatial planning elements characterizing flood prone areas could be transformed into critical urban risk management options for DRR. This is because a spatial planning elements were found to have a direct influences on critical factors of DRR such as location of activities. The study concluded by recommending a number of spatial planning strategies that can be vaporized for DRR. Such strategies are systematically aligned to the unique vulnerability context conditions associated with the two flood vulnerability solution arrived at using HCA. / NRF
188

Strategic Environmental Assessment Pre-Study of That Luang Marsh : For Sustainable Development in Vientiane Capital, Lao PDR

Olsson, Fredrik January 2010 (has links)
IntroductionLao People Democratic Republic (Lao PDR / Laos) has a population of 5.8 million people and is today one of the least developed countries in Asia. That Luang Marsh (TLM) is the largest remaining urban wetland (2000 hectare) in Vientiane Capital, which historically has supplied wildlife and local people with several eco-services. Some important functions are wastewater treatment, flood control (water storage), and several agricultural and aquacultural services. Due to the flat landscape and the low permeability in soil, the area becomes naturally flooded during the wet season when the water level in the Mekong River is high. All storm water in Vientiane is drained through TLM. There have been several projects in Vientiane aimed to solve the drainage and sanitarian situation. However, the problems have still not been completely solved today. Aim and objectives This Master of Science thesis aims at providing a prestudy for a Strategic Environmental Assessment (SEA), which may be used for creating a full-scale SEA in the future. The main objectives that will be analyzed are: Wastewater treatment in Vientiane. The environmental impact caused by human activity and how it can be reduced in TLM / Vientiane / Mekong River. Sustainable development in Vientiane. The need of SEA in TLM. Flood control in Vientiane. • Agriculture and aquaculture in Vientiane. The WATER Project and New Town Development Project. Socioeconomic overview of Laos / Vientiane. Methodology This thesis is a collaboration between the Swedish university KTH and the Thai university AIT. The student (author of this report) was linked to Dr. Shipin, co-advisor at AIT through Dr. Frostell, supervisor at KTH, and Dr. Berg. A field study was made from October 2008 - December 2008 in Vientiane Capital, Laos. The student has collected information from NGOs, institutions, departments, laboratories, libraries, local people, and Internet in the form of hardcopy literature, electronic documents, e-mail contacts, and interviews. During two days the student had the favour to join a team sent out by WWF for collecting water samples around the marsh. The team consisted of representatives from WWF and the three districts that surround That Luang Marsh. Strategic Environmental Assessment The main purpose of a SEA is to support sustainable decision-making processes in an area. Except from environmental aspects, the SEA also considers socioeconomical aspects. SEAs may differ in terminology and practice between countries and organisations but do usually include stages like preliminary scan, conduction of SEA, preparation of the report, implementation of SEA in PPP (policy, plans, or programmes), and review of the implementation. This report gives a short briefing about how SEAs are produced by CIDA (Canadian International Development Agency) and according to the European Directive. The European Directive is the standard SEA for several European countries. The report does also present the project oriented EIA (Environmental Impact Assessment) Wetland valuation Wetlands may be valuated in different ways. This report explains one method where the valuation is separated into: DUV (Direct Use Value), IUV (Indirect Use Value), OV (Option Value), and NUV (Non Use Value). These are added to TEV (Total Economical Value). WATER Project The WATER project is a response to the environmental and socioeconomical problems that have occurred in Vientiane. Several past projects have been less successful, which have resulted in adverse impact on the society and the ecosystem. The WATER project tries to highlight the wetland values and convince authorities to use CWs (Constructed Wetlands) instead of conventional wastewater treatment plants for treating wastewater. This project will first do five pilot studies in Vientiane. Three will be used for treating domestic wastewater and two for industrial. The project is a part of the Wetland Alliance Programme. Main partners during the project are the government of Lao PDR, WWF Laos, WWF Germany, Wild Fowl & Wetland Trust (WWT). Other involved partners are CORIN, AIT, WFC, CIDA, and Sida. It seems that the authorities will allocate 22 hectares for constructing a CW that will purify Vientiane’s most polluted urban water canal Hong Ke. The WATER Project recommends that even Hong Xeng is included which totally requires 61 hectare CW area. New Town Development Project The New Town Development is a collaboration between the Lao and Chinese government. The plan is to develop the city so it attracts more foreign and domestic investors. 1000 hectares low valued land will be developed for business and 200 hectare will be used for creating an artificial lake aimed for compensating lost wetland area. As a part of the negotiations, the Chinese has already constructed a stadium that was used during the SEA Games 2009. 670 hectare will be developed in TLM, 100 hectare in Dongphosy Forest, and 430 hectare close to the new stadium. The Chinese investors will lease the developed land for 50 years. This may be used for business. When the project period is over, the Lao government have the right to reclaim all developed land without compensation. The Chinese Suzhou City stands as model for the development project in Vientiane. The estimated cost of the project is USD 800-1000 million. Discussion and conclusions Choosing SEA, CEA (Cumulative Effect Assessment), or another strategic assessment method should not be the main issue. As long as the method contributes to a strategic sustainable development and is internationally accepted it may be used for PPPs. The main issue of SEA is not to create a report, but convincing authorities about the importance of sustainable decision-making processes. Factors that may inhibit a sustainable development in Laos are low education, corruption, and greedy investors that devastate the environment for own profit. The laws are in several cases enough but due to the lack of a judicial organization and economical funding the legislative system becomes inefficient. It is difficult to valuate wetlands. The greatest challenge is to valuate OVs and NUVs. OVs are difficult because they are just options. NUVs are based on a subjective estimation because these consider cultural and aesthetical values. A problem with the New Town Development Project is that some vulnerable groups that live in TLM will be forced to live in a resettlement area. These people may have difficulties to adapt to the new environment. It is important that the authorities work extra hard with helping project affected people. Wetland degradation is probably a result of i) intense water pollution (wastewater from households and industries), ii) physical destruction (housing, filling, and artificial drainage), iii) overuse of wetland VI resources, iv) invasions or invitations of new species (golden apple snail). In theory, wetlands may be replaced with modern technology for protecting the city against flooding. One way is to build a cement layer in Houay Mak Hiao River for increasing the drainage capacity. However, because the country has very small economical margins and the hydrological situation is not completely investigated, this could be treated as a risk project. Another problem is that the wastewater capacity will reduce and the biodiversity in the river will be lost. The loss of wastewater treatment needs to be compensated with modern technology. Something needs to be done for increasing the sanitarian situation in Vientiane. This report has compared the benefits of using conventional wastewater treatment plants and CWs. Probably the most reasonable solution is to use a CW for treating the wastewater in Hong Ke while the new centre in TLM uses a conventional wastewater treatment plant. This is an optimal solution because a conventional wastewater treatment plant for treating the water in Hong Ke would require a completely new sewage system, which could become very expensive. Maintaining a conventional wastewater treatment plant is also expensive and requires special trained staff. An easier alternative would be to use CWs for the old part of Vientiane. Because the new centre will be built in a modern style with new infrastructure this part of Vientiane could treat wastewater conventionally. Building a conventional wastewater treatment plant would also save some high-valuated land. Conventional Wastewater TreatmentAdvancedStandardizedQuick turnover timeRequire small spaceCould be more sanitarianProcesses better evaluated Constructed WetlandLong lifetimeEffective in warm climatesNo chemical inputEasy to maintainLow sludge productionAestheticalLess need to change infrastructureLow running cost (flat topography) The author will not decide if Vientiane should develop into a top modern city or remain as a small sized capital as it is today. However, today the situation is unsustainable and something needs to be done. Better organization and planning is necessary for not repeating mistakes that were made during past projects. All decisions have to be based on a non-corruptive process and sustainable thinking. Integrating an environmental and socioeconomical strategy into the future of Vientiane should be of interest for all Laotians. Vientiane is the economical centre of Laos and an increased discharge of polluted water into the Mekong would increase the stress of the important river. A collapse of the biodiversity in the Mekong would strike hard on Laos’ fishing industry and economy. Decisions made today will surely more or less affect people at local, regional, national, and international level in the future. / Inledning Mänsklig aktivitet har på vissa håll resulterat i en allvarlig miljöpåverkan. Laos har en befolkningsmängd på 5,8 miljoner invånare och räknas idag som ett av Asiens minst utvecklade länder. That Luang Marsh (TLM) är huvudstaden Vientianes största urbana våtmarksområde (2000 hektar). Våtmarksområdet bjuder på flertalet ekologiska tjänster som under historiens lopp gynnat både människor och djur. Några av dessa är naturlig vattenrening och översvämningsskydd (vattenlager). Våtmarken bidrar till ett rikt jordbruk och akvakultur. Under regnperioden stiger vattennivån i Mekongfloden så att området naturligt svämmas över. Dräneringen av Vientiane försvåras eftersom landskapet är platt och permeabiliteten i jorden är låg. Huvudsakligen flödar vattnet ut via TLM och floden Houay Mak Hiao innan det når Mekongfloden. Flertalet projekt har försökt effektivisera Vientianes dräneringseffektivitet och minska de sanitära problemen. Dock finns det en hel del kvar att göra. Syften och mål Detta examensarbete är en förstudie till en Strategic Environmental Assessment (SEA). Förstudien skulle kunna utnyttjas till uppbyggandet av en komplett SEA. Huvudområden som undersöks i denna rapport är: Vattenreningen i Vientiane. Den mänskliga miljöpåverkan och hur denna kan lindras i TLM / Vientiane / Mekongfloden. Hållbar utveckling i Vientiane. Behovet av SEA i TLM. Översvämningsskydd i Vientiane. Jordbruk och akvakultur i Vientiane. Projekten WATER Project och New Town Development Project. En socioekonomisk översikt för Laos /Vientiane. Metod Projektet är ett samarbete mellan det svenska universitet KTH och det thailändska universitet AIT. Författaren till denna rapport, Fredrik Olsson är mastersstudent på KTH och har genomfört och utvecklat projektet tillsammans med handledaren Dr. Frostell, KTH och bihandledaren Dr. Shipin, AIT. Även Dr. Berg har haft en viktig roll i utvecklandet och det praktiska genomförandet av projektet. Oktober 2008 – december 2008 genomfördes fältstudier i Vientiane, Laos. Fakta till rapporten inhämtades främst från NGOs (Non- Governmental Organizations), institutioner, laboratorier, bibliotek, lokalbefolkning och internet. Detta skedde i form av tryckta papper/avhandlingar, elektroniska dokument, e-mail kontakter samt intervjuer. Under två dagar genomfördes fältstudier i TLM i samarbete med WWF. Syftet var att mäta vattenkvaliteten i våtmarken på ett antal förutbestämda platser. Gruppen bestod av en representant från WWF samt representanter från de tre distrikt som delar TLM. Strategic Environmental Assessment (Strategisk Miljöbedömning) Syftet med en SEA är att skapa hållbarhet i myndigheters beslutsprocesser. SEA integrerar både miljö och socioekonomiska aspekter i samma studie där målet är att sträva mot en hållbar utveckling. Olika SEA kan skilja sig i utformningen beroende på vilken handledning som används. Dock är dessa skillnader små och inträffar oftast i form av annorlunda terminologi och utförande. Normalt ingår moment som preliminär undersökning, genomförande av SEA, förberedelse av rapport, implementering av SEA i PPP (Policy, Plan och Program) samt utvärdering av implementeringen. Den här rapporten redovisar ytligt hur VIII en SEA genomförs enligt CIDA-modellen (Canadian International Development Agency) och enligt Europeiska Direktivet. Den senare handledningen används som standard i flertalet europeiska länder. Denna rapport kommer även att redovisa grunderna i EIA (Environmental Impact Assessment). Värdering av våtmarker Det finns ett antal olika sätt att värdera våtmarker. Ett sätt som redovisas i rapporten är att separera värderingsområdena till DUV (Direct Use Value), IUV (Indirect Use Value), OV (Option Value), och NUV (Non Use Value). Dessa summeras sedan till TEV (Total Economic Value). DUV beskriver de direkt synliga värdena av att bevara en våtmark, IUV de värden som är indirekta, OV de värden som kan vara möjliga i framtiden, NUV de värden som inte kan bedömas ur ett ekonomiskt och TEV våtmarkens sammanlagda värde. WATER Project Detta projekt är ett svar på de sanitära och ekologiska problemen som förekommer i Vientiane. Flertalet projekt har varit mindre framgångsrika vilket påverkat både samhället och ekosystemet negativt. För att råda bot på de sanitära problemen pågår för närvarande ett försök att informera myndigheterna om fördelarna med att bygga konstruerade våtmarker. Dessa skulle kunna vara ett alternativ till konventionella reningsverk. För att bevisa våtmarkernas effektivitet planeras nu byggandet av fem pilotanläggningar i Vientiane. Tre kommer användas för att rena kommunalt avloppsvatten medan två är avsedda för industriellt bruk. Projektet är en del av Wetland Alliance Programme. Samarbetspartners för WATER Project är laotiska staten, WWF Laos, WWF Tyskland och Wild Fowl & Wetland Trust (WWT), CORIN, AIT, WFC, CIDA och Sida. Indikationer tyder på att konstruerade våtmarker (22 hektar) kommer att byggas för rening av vattnet i dräneringskanalen Hong Ke. Detta är Vientianes mest förorenade kanal. Dock önskar WATER Project att totalt 61 hektar avsätts så att även kanalen Hong Xeng kan renas. New Town Development Project Projektet är ett samarbete mellan den laotiska och kinesiska staten. Planen är att ett omfattande utvecklingsprojekt ska locka flera utländska och inhemska investerare till Vientiane. Totalt kommer 1000 hektar lågt värderad mark att kommersialiseras. Ytterligare 200 hektar kommer att användas till byggandet av en konstgjord sjö som kompenserar för förlorad våtmarksyta. Kineserna har i gengäld lovat att bygga en sportarena för SEA Games 2009. 670 hektar kommer exploateras i TLM, 430 hektar i närheten av den nya sportarenan och 100 hektar i Dongphosy skogen. Kinesiska investerare kommer att arrendera marken under 50 år. Under denna period kan investerarna fritt göra affärer och har rätt att sälja marken till vem de vill. När 50 år har passerat har den laotiska staten rätt att ta tillbaka den arrenderade marken utan kompensation. Som modell för utvecklingsprojektet står kinesiska Suzhou City. Projektet beräknas kosta 800-1000 miljoner amerikanska dollar. Diskussion och slutsats Det spelar ingen större roll vilken metod som används för att nå en hållbar utveckling om den har någon form av internationell acceptans, är strategisk och tar hänsyn till att integrera både miljö och socioekonomiska frågor i samma studie. SEA och CEA (Cumulative Effect Assessment) är endast några alternativ. Målet med en SEA är först och främst inte avsedd för att skapa en rapport utan snarare hållbarhet i beslutsprocesser på PPP-nivå. Faktorer som motverkar hållbar utveckling i Laos är bland annat korruption, dålig utbildning och giriga investerare som maximerar sina ekonomiska vinster på miljön och samhällets bekostnad. Det är svårt att värdera OV eftersom denna parameter endast tar hänsyn till möjliga framtida värden. Samtidigt är NUV näst intill omöjligt att värdera eftersom denna parameter värderar kulturella och etiska värden. Värderingen av NUV blir då en subjektiv bedömning. Under New Town Development Project kommer flertalet människor i TLM tvingas flytta till en mer urban miljö. Dessa grupper är ofta speciellt sårbara eftersom de har bristfällig kunskap om urbana arbeten. Det är extra viktigt att myndigheterna följer upp dessa människor så att deras lidande minimeras. Förstörelsen av våtmarker beror troligtvis på i) stor tillförsel av vattenföroreningar (kommunalt och industriellt avloppsvatten), ii) fysisk destruktion (husbyggen, utfyllnad och konstgjorda dräneringssystem), iii) överutnyttjande av våtmarksresurser samt iv) invasioner och införanden av främmande arter som till exempel ”golden apple snail”. Teoretiskt skulle det vara möjligt att ersätta våtmarker med moderna tekniska lösningar för att undvika översvämningar. En lösning skulle vara att floden Houay Mak Hiao beläggs med ett cementlager för att öka vattenflödet ut från Vientiane. Dock har landet mycket svårt att finansiera denna typ av projekt och efterkommande underhåll på grund av små ekonomiska marginaler i statens budget. Det är heller inte helt kartlagt hur hydrologin i området fungerar. Ett annat problem med denna typ av lösning är att Houay Mak Hiaos vattenreningskapacitet och biodiversitet går förlorad. Om projektet genomförs måste vattenrening ske på annat sätt. Den här rapporten har försökt jämföra fördelarna med att använda konstruerade våtmarker (CW) istället för traditionella vattenreningstekniker. Att använda CW för att rena vattenmassorna i Hong Ke (avloppsvatten från gamla Vientiane) är nog det enklaste och billigaste alternativet medan den nya stadsdelen i mitten av TLM skulle kunna utrustas med ett konventionellt reningsverk. Detta eftersom de utländska stadsutvecklarna antagligen kommer ha tillräckligt med medel och kunskap för att stödja modern vattenreningsteknik som rymmer inom New Town Development Project. Infrastrukturen för att använda konventionella reningsverk är inte tillräckligt utvecklad i resterande Vientiane så att bygga ett konventionellt reningsverk i dessa delar av staden kan bli kostsamt. Dock blir situationen en annan i den nya stadsdelen eftersom denna byggs upp från grunden. Eftersom marken beräknas få ett avsevärt högre marknadsvärde kommer antagligen modern reningsteknik spara en del yta. Fördelar med konventionella reningstekniker är att dessa allmänt är mer avancerade, standardiserade, har en snabb omsättningstid på avloppsvattnet, är mindre platskrävande och processerna i dessa verk är bättre kartlagda. Däremot kan CWanläggningar användas under en längre tidsperiod, de har en hög effektivitet i varma klimat, har låg slamproduktion, kräver mycket små tillsatser av kemikalier, är enkla att underhålla, är mer estetiska, kräver enklare infrastruktur och har en låg driftskostnad. Författaren till denna rapport kan inte avgöra om det bästa för staden är att utvecklas till ett modernt urbant komplex. Dock är den nuvarande situationen ohållbar och därför bör någon form av åtgärder vidtas. Om organisationen och planering inom och mellan projekt förbättras minskar risken för misslyckade projekt. Det är viktigt att alla beslut som fattas grundas på ett korruptionsfritt hållbarhetstänkande. Om Vientiane strävar mot att ta ett större ansvar för miljö och socioekonomi så kommer landet som helhet att gynnas, eftersom huvudstaden är motorn i Laos ekonomi. Ett ökat okontrollerat utsläpp av vattenföroreningar från Vientiane kommer att öka belastningen på Mekongfloden. En biodiversitetskollaps i Mekongfloden skulle få allvarliga konsekvenser för landets fiske och ekonomi. De beslut som fattas idag kommer i framtiden att mer eller mindre påverka människor på ett lokalt, regionalt, nationellt och internationellt plan.
189

Posouzení účinnosti realizovaných prvků plánu společných zařízení KPÚ Hať a Darkovice / The assessment of efficiency of the system common facillities in Hať and Darkovice cadastral areas

Moravcová, Aneta January 2012 (has links)
The target of the diploma thesis was the assessment of efficiency of the system of common facilities in Hať and Darkovice cadastral areas. Digital model of elevation was made by software Atlas DMT. Average soil loss by soil erosion of given subbasins was evaluated by ArcGis tools before and after the design of conservation measures. Polder’s efficiency was evaluated also. Another part of thesis offers alternative design of erosion and flood control.
190

Fortel aneb postav si dům / Dexterity, or build your house

Netrefová, Klára Unknown Date (has links)
The design of anthropoid / metamorphosis loosely follows the pre-diploma project Fortel or so called "build a house" when I decided to "put my hand to the work, cut, drill, fold…" and to rediscover the imprints of work and tools in the mass from which they disappeared due to the mass production. The output of the project was an eclectic, crumbling garden of prefabricated bricks. Capillary (open) porosity usually occurs in brick products. It allows the penetration and retention of a relatively large amount of water. The bricks are made of natural mineral raw materials, as well as expanded clay, which is commonly used as a hydroponic substrate. At the same time, the porosity of the brick blocks causes future degradation of the material in the exterior. The disrupted "worked" ceramic blocks in the garden burst, mix with the substrate and create a breeding ground for plants. In my diploma thesis I move away from materials formed into modules, imported to the construction site, and I deal with matter in its freest fluid form and forms arising in-situ. The work is permeated by three fluid media, water, clay and concrete. Concrete - initially a fluid material, takes the form of two other materials, solidifies. Clay - as a semi-solid - semi-fluid material Water - infinitely fluid material, still present, rapidly transforms, and periodically comes and disappears, transforms the other two materials. The materials mix together, form into matter, then drain and disintegrate and disappear when their time comes. With these nature-friendly processes, the design works on three scales. On a micro scale, matter decomposes into gravel, sand, loess, which nourishes soils and plants, and allows an environment suitable for a variety of animals. In the middle scale, these are small objects that shape and manipulate the landscape. And in a big scale, it is co-working with the landscape itself.

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