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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.
221

Designing successful stakeholder participatory processes for environmental planning: A case study of subwatershed planning in Hamilton, Ontario

van der Woerd, Mark 27 August 2009 (has links)
Stakeholder participation has become a valuable tool for agencies in the field of environmental planning. The potential benefits, for both agencies and individuals, of involving stakeholders in the planning process have been widely recognized and well documented. However, the success of participatory initiatives depends on the extent to which local stakeholders are interested in, and capable of, becoming involved in the process. Thus, the outcomes for each process vary as planning issues are dependent on their local context. This study aimed to evaluative the characteristics of successful stakeholder in planning. Specifically, it strived to obtain an understanding of successful stakeholder engagement through developing and integrating an evaluative framework based on the literature with the motivations and perceptions of agencies representatives and local stakeholders. In order to achieve these goals, the evaluative framework was applied to a case study of the Tiffany Creek subwatershed in Hamilton, Ontario. The case study revealed that determining and incorporating the opinions of agencies and stakeholders toward a participatory process can shed light on the characteristics of successful stakeholder participation in a given region. The characteristics of successful stakeholder participation and the integration of agency and stakeholders viewpoints into the planning process are discussed and recommendations to improve participatory processes in environmental planning are provided.
222

Development of management strategies for Kaoping River Basin using NPS pollution and river water quality models

Lai, Yu-Chang 16 August 2010 (has links)
The Kaoping River basin is the largest and the most intensively used river basin in Taiwan. It is 171 km long, drains a catchment of more than 3,257 km2, and has a mean flow of 239 m3/s. It serves as a water supply to the Kaohsiung City (the second largest city in Taiwan), several towns, two counties, and a number of large industries (electronic, steel, petrochemical, etc.). Although the mean annual rainfall in this river basin is close to 3,000 mm, over 90% of which appears in the wet season. The period of high flow rate in the stream usually occurs in the late spring and summer due to the impacts of monsoon and typhoon. Non-Point Sources (NPS) pollutants, which are associated with stormwater runoff from agricultural land uses can be quite diffuse and difficult to treat. In this study, land use identification in the basin was performed by properly integrating the skills of geographic information system (GIS) and global positioning system (GPS). Remote sensing image and Digital Elevation Model (DEM) of Kaoping River Basin were applied for the land use identification task. An integrated watershed management model (IWMM) was applied for simulating the water quality and evaluating NPS pollutant loads to the Kaoping River. The watershed was divided into catchments and river segments. The land use patterns were defined by the surface coverage of each catchment. The underneath soil can have several layers, and each land use has its vegetation characteristic and erosion coefficient. The model was calibrated and verified with field data from water quality monitoring stations. The calibrated model was used to develop best management practices (BMP). Moreover, the Water Quality Analysis Simulation Program (WASP) was also applied for the water quality simulation. The model was calibrated and verified with water quality data, and the model was used to analyze the impacts of NPS loading on water quality. The major objectives of this study were to (1) investigate and identify the current contributions of NPS pollutants to the Kaoping River pollution, (2) perform the land use identification and construct the watershed GIS to effectively manage the watershed, (3) perform water quality and soils sampling and analyses, (4) apply multimedia models for NPS pollution evaluation and water quality simulation, and (5) evaluate the effectiveness of the applied remedial strategies on watershed management and water quality improvement. This study identified major land-use patterns in Kaoping River Basin using SPOT images and GIS/GPS/RS techniques. The major findings from the GIS, field, and modeling tasks include the following: (1) Fourteen types of land-use patterns in the watershed area of the basin were classified with the aid of the Erdas Imagine process system; (2) Orchard gardens, rice paddies, sugarcane fields, betel palm farms, and tea gardens dominate the farmland areas in the basin and are scattered around on both sides of the river corridor; and (3) Simulated results indicate that NPS pollution plays a significant role in the deterioration of the downstream water quality of Kaoping River and caused a significant increase in suspended solids loads into the basin¡¦s water bodies. Concern about the deteriorating condition of the river led the Government of Taiwan to amend relevant legislation and strengthen the enforcement of discharge regulations to effectively manage the river and control pollution. Based on the results of this study, application of BMPs [e.g., source reduction, construction of grassy buffer zone, and land-use management] for NPS pollutant control are required. Multimedia modeling results indicate that the application of the following specific BMPs can reduce the effects of NPS suspended solids pollution on the water quality of Kaoping River: (1) Conversion of farmlands on hillsides of the upper catchment to forest; and (2) Conversion of rice paddies and agricultural lands to buffer zones (e.g., grassy strip, detention pond, and constructed wetland) along the riverbank areas of the three sub-basins. With application of these two proposed BMPs, the peak suspended solids concentrations in the wet seasons could be significantly reduced. Results and experience obtained from this study will be helpful in designing the watershed management strategies for other similar river basins.
223

Development of river water quality and sediment management strategies

Lin, Chih-En 24 August 2010 (has links)
The river water quality management strategy involves a series of complex inter-disciplinary decisions based on speculated responses of water and sediment quality to changing controls. In the aquatic system a rapid removal of the heavy metals from the water to sediments may occur by settling particles while some of these pollutants can be mobilized by getting accumulated into the biota from the sediments sink. Thus, sediment plays a major role in the determining pollution pattern of aquatic systems. It acts as both carriers and sinks for contaminants, reflecting the history of pollution, and providing a record of catchment inputs into aquatic ecosystems. The Yan Shuei Gang River watershed is one the river watersheds in Kaohsiung City, Taiwan. It is 5-km long, drains a catchment of more than 1,200 ha. Part of the river water is from the domestic drainage areas located in the upper catchment. In Linhai Industrial Parks, there are more than 493 registered industrial factories that discharge their wastewater into the Yan Shuei Gang River. Thus, recent water and sediments quality analysis indicates that the Yan Shuei Gang River is heavily polluted. The major objectives of this study were to (1) perform water quality and sediments sampling and analyses, (2) perform water quality simulation and demonstrates the model application to the Yan Shuei Gang River, (3) assess the water and sediments quality, (4) provide foci for immediate remediation efforts, (5) provide benchmark levels to test outcomes of future remediation efforts, (6) design a novel extraction technique that utilizes a mildly elevated pressure in consecutive cycles with a chelating agent for the sediment slurry. Water quality investigation results show that the biochemical oxygen demand (BOD), ammonia-nitrogen (NH3-N), and suspended solid (SS) average concentrations in water samples of the Salt-water River varied from 10.2 to 194, 8.51 to 18.3, and 7.9 to 19.5 mg/L, respectively. The results of the chemical analysis of the Salt-water River surface sediments showed that the sediments present highly elevated Cd, Cr, Ni, Cu, Pb, Zn and Fe concentrations. Investigation results reveal that sediment samples contained significant amount of iron (up to 3.6%), Cr (up to 66.5 mg/kg), Pb (up to 36.5 mg/kg), Ni (up to 43 mg/kg), and Al (up to 1.8%). All heavy metal concentrations were higher than the world average, sediments average and sediment quality guidelines (SQGs). Although all metals showed varied concentrations, the approaches of factor analysis, normalized enrichment factor (EF), and the geo-accumulation index (Igeo) proposed in this paper were effectively used to differentiate the natural and anthropogenic sources of the metals. Both the EF and Igeo indicated similar anthropogenic contamination degree of the metals. The potential acute toxicity in sediment of Yan Shuei Gang River was observed to be mainly due to Cu contamination. Cu was the major toxicity contributor accounting for 32-46% of the total toxicity in Salt-water River, followed by Zn. The Water Quality Analysis Simulation Program (WASP) model developed by US Environmental Protection Agency (EPA) was selected as a water quality planning tool to perform the water quality evaluation. Modeling results show that the current daily pollutant inputs were much higher than the calculated carrying capacity for nutrients and BOD of the Yan Shuei Gang River. Based on the results from this study, the following remedial strategies have been proposed to minimize the impacts of industry and domestic source pollution on the water quality of Salt-water River: (1) increase the flow by transporting 1 m3/s unpolluted surface water from other sources to dilute the polluted river water, (2) construction of the intercepting systems to effective intercept and transport the untreated wastewater to the wastewater treatment systems. The sediments batch extracted by 150 psi pressure cycles has the most Cu removed rater (70%), much higher than without treatment (55%) or with 90 psi pressure cycles treatment (65%). Pressure-assisted extraction achieves in 60 min the amounts of Cu equal to or exceeding those achieved in 240 min without pressure cycles under the same concentration conditions. This research indicates that the advantages of pressure cycle system are increased process speed, more thorough extraction, and reduced use of the chelating agent. The heightened treatment is explained by sediments aggregate fracturing upon pressure cycles that exposes the contaminants as well as by the chelating agents. The technique is expected to accelerate extraction treatment of a wide range of heavy metal contaminants, and it may provide treatment to dredged and stored contaminated sediments. Experience obtained from this study will be helpful in designing the sediment and river management strategies for other similar river watersheds.
224

Development of remedial strategies for the Lover River: a case study of urban river management

Tsai, Yu-Yi 01 September 2011 (has links)
Due to the impact of Taiwan geography and topography, flow rate in rivers goes up and down intensely with rainfall. Rivers are usually lack of dilution capacity, especially during dry season with little rainfall. Water quality has been damaged by untreated municipal wastewater, industrial wastewater and landfill leachate discharged into rivers through gutters, hidden pipes or tributaries discharger, especially obvious in metropolitan rivers. Love river is a typical metropolitan river. It has been under restoration by stages since 1977. Due to the lack of restoration in its upstream segments, this project is to analyze current water quality and to estimate pollutant loading through integration of related materials and documents in Love rivers, as well as to simulate water quality by WASP model through the analyses of measurement data for main and tributaries dischargers as the evaluation of pollution improvement action. Past water quality analyses shows that most upstream segments (upstream of sluicegate under water in Baozhu gutter) are between medium and serious polluted. In addition, results of water quality and flow rates in tributaries discharger shows that (River Pollution Index, RPI) in southern discharger left to Yucheng bridge, K trunk discharger and Baozhu gutter discharger are between 7.25 to 8.25, indicating that this tributaries discharger is the primary source for Lover river pollution. The objectives of this research are to lower the level of upstream pollution through the policies provided through related restoration experience before the sewage system for Kaohisung city is completely developed. As shown by the simulation of pollution reduction, through the combination of water interception and water injection, biochemical oxygen demand and ammonia nitrogen in water segments downstream of Dingxin bridge was reduced above 65% and 50%, respectively. The fact that water is discharged into Love river after purification by the combination of water interception and source water treated by water purification engineering is beneficial for the reduction of downstream biochemical oxygen demand and ammonia, as well as the improvement of dissolved oxygen to eventually meet the goal of lowering levels of water pollution. The Forecast results of the water quality model used in this study can evaluate the cost-efficiency of pollution reduction action and to provide priority restoration policy in the future as references in the following studies.
225

Simulating and Optimizing Storm Water Management Strategies in an Urban Watershed

Damodaram, Chandana 2010 December 1900 (has links)
Land development transforms the natural landscape and impacts in stream ecosystems and downstream communities as it alters the natural flow regime. An increase in impervious areas results in higher volumes of storm water runoff, reduced time to peak, and more frequent flooding. Best Management Practices (BMP) and Low Impact development (LID) are a few of the set of measures which are used to mitigate the impact of urbanization. Peak flow, runoff volume are few of the conventional metrics which are used to evaluate the impact and performance of these storm water management strategies on the watershed. BMP are majorly used to control the flood runoff but results in the release of large volumes of runoff even after the flood wave passed the reach and LIDs are used to replicate the natural flow regime by controlling the runoff at the source. Therefore need to incorporate a metric which includes the timing and area being inundated needs to be considered to study the impact of these strategies on the downstream. My proposed research will focus on simulating the Low Impact Development (LID) techniques like permeable pavements and rainwater harvesting on an urbanized watershed using a curve number approach to quantify the hydrologic performance of these strategies on the watershed. LID, BMPs, and combined strategies are introduced for retrofitting existing conditions and their hydrologic performance is accessed based on the peak flow and a new metric Hydrologic Footprint Residence. A simulation optimization framework would be developed which identifies cost effective LID options that maximize the reduction of peak flow from the existing condition design storms while meeting budget restrictions. Further LID and BMP placement is included in the optimization model to study the impact of the combined scenario on the storm water management plans and their performance based on different storms and corresponding budget. Therefore a tradeoff can be illustrated between the implementation cost and the hydrological impact on the watershed based on the storm water management approach of using only LID and combination of LID and BMP corresponding to varied spectrum of design storm events.
226

Measuring the Effectiveness of Educational Tools and Hyrdologic Metrics in Raising Awareness About Stormwater Sustainability

Scott, Tommi Jo Grace 2011 August 1900 (has links)
Urbanization of watersheds leads to the degradation of watershed health, as increased areas of imperviousness produce alterations in the flow regime of receiving water bodies. While centralized infrastructure improvements, such as detention ponds, are typically implemented to manage excess runoff, a more decentralized approach that utilizes Low Impact Development (LID) design principles may better preserve the predevelopment flow regime. Peak flow is traditionally used to design both of these types of infrastructure, but this does not capture the changes in the flow regime, nor does it convey the importance of stormwater sustainability to the general public. To further the general public's understanding about stormwater sustainability, an educational tool was used to take a complicated issue and make it easier to understand by a layperson. The first purpose of this work was to explore the effectiveness of educational tools that may be developed to increase public awareness about issues of watershed sustainability and encourage adoption of sustainable stormwater controls. To increase knowledge about stormwater sustainability and encourage more sustainable practices, a new stormwater sustainability metric, the hydrologic footprint residence (HFR), was recently introduced to measure more holistically the impacts of urbanization on the downstream residence. HFR measures changes to the flow regime as the area of land inundated for one unit of time in response to one rainfall event, which is a more relatable metric than peak flow for the general public. It was the second purpose of this work is to explore the effectiveness of HFR in communicating the impacts of urbanization on watershed health, as compared to traditional stormwater metrics, such as peak flow. To test these different objectives, collaboration with the Communication and the Computer Engineering Departments at Texas A&M University was needed to create a survey, which helped evaluate the effectiveness of the educational tool in educating the general public about stormwater sustainability, and encouraging more sustainable practices. The survey was also used to evaluate and compare the use of HFR and peak flow within the quiz for communicating to the general public about stormwater sustainability. Results indicated the quiz was useful for educating the public about stormwater sustainability, encouraging more sustainable practices. In addition, results indicated the HFR was more effective than peak flow in educating the public about LIDs.
227

Stakeholder participation in watershed permitting in the Powder River Basin of Wyoming satisfaction, success, discourse, and knowledge /

Soltis, Jeffrey J. January 2008 (has links)
Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on August 7, 2009). Includes bibliographical references (p. 77-83).
228

The contribution of environmental history to the development of a model to aid watershed management a comparative study of the Big Darby Creek and Deer Creek Watersheds in Ohio /

Dameron-Hager, Irene F., January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xiii, 253 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Earl F. Epstein, Dept. of Natural Resources. Includes bibliographical references (p. 228-238).
229

An investigation of spatial and temporal variability in several of Montana's reference streams working toward a more holistic management strategy /

Makarowski, Kathryn Elizabeth. January 2009 (has links)
Thesis (MS)--University of Montana, 2009. / Title from author supplied metadata. Includes bibliographical references.
230

Characterization and recommendations for the remediation of acid mine drainage impacted streams

Hudnall, Patrick F. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xii, 170 p. : ill. (some col.), maps (part col.). Includes abstract. Includes bibliographical references (p. 112-116).

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