Spelling suggestions: "subject:"water resources managemement"" "subject:"water resources managementment""
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Community decisions about innovations in water resource management and protectionHoule, James J. 29 January 2016 (has links)
<p> The purpose of this study was to investigate the social, economic and technological factors that influence rates of adoption of innovative stormwater management approaches in municipal organizations in the Great Bay watershed, NH. The scope of this study was to investigate how innovations spread through municipal populations in a specific region and watershed area of the US. The methodology used mixed qualitative methods, including semi-structured interviews, case studies, and surveys to examine perceptions, attitudes, and beliefs that influence the adoption of innovative stormwater management solutions, as well as the governance characteristics of municipalities at different stages of adoption. Major findings include: adopter categories can be relatively easily and quickly categorized into early and late majorities as a preliminary means to identify populations of ready and willing audiences interested in and capable of advancing innovations; early and late adopter classifications followed general diffusion theory, but differed in substantial ways that could influence overall project or program success; and finally that early majority communities have more internal and external capacity to advance innovations as well as higher levels of peer-to-peer trust to offset perceptions related to economic risk that can either advance or stall innovative stormwater management solution adoption. This research offers insights on how to allocate scarce resources to optimally improve water quality through stormwater management solutions, and makes recommendations for how to effectively and efficiently generate greater understanding of complex barriers to adoption that thwart innovation in municipal governance organizations. One significant implication is that agents of change who want to move innovations through a broad municipal population should focus their efforts on working with innovators and early adopters that have status within relevant peer networks and who have capacity to evaluate the strengths and weaknesses of innovations.</p>
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Water consumption for steam methane reforming hydrogen plants in Edmonton, CanadaShah, Jignesh 13 July 2016 (has links)
<p> Traditional engineering and financial assessments are limited not only to consideration of currently internalized costs, but also often lack consideration of new or current externalities during the life of the new system. The goal of this thesis is to provide a methodology that integrates sustainability assessment with the traditional assessments, thereby allowing the assessment and optimization of the total overall costs. The proposed method is applied for the steam methane reforming (SMR) plants operated by Air Products in Edmonton, Canada where the boiler feed water for hydrogen manufacturing is produced using the polished effluent from the local municipal wastewater treatment plant. The softening of the feed water to Reverse Osmosis (RO) system is proposed (after evaluating the several options) to improve the recovery for the current RO system from 75% to 95%. The overall costs were estimated for comparison of the current and proposed systems.</p><p> The production of hydrogen via SMR highlights the complexities of the sustainability assessment. While hydrogen may be considered a renewable transportation fuel, depending on whether the fossil natural gas can be replaced with renewable biogas or via electrolysis of water using renewable energy, it is reliant on the availability of water. However, water is a scarce resource that is also essential for basic human survival and ecological needs. As the population of the world increases, alternative water sources need to be explored, which may require more energy in the processing of such water to potable grade. </p><p> The results show that the proposed RO feed softening via Ion Exchange (IX) can improve RO recovery up to 95%. The financial assessments based on literature prices and cost factors show that the current operating cost can be reduced up to ~20% by improving RO recovery to 95% with ~75% probability for cost reduction at 95% recovery. When the capital costs are accounted for, NPV-based analyses show that for 95% recovery more than 20% IRR (if spare vessels are available for refurbishment) could be achieved.</p><p> Environmental assessments (Life Cycle Assessment method using SimaPro v7.3 following ISO 14040-44 standards) show that 1.12 x 10<sup>-3</sup> ReCiPe Endpoints impact for current RO operation at 75% recovery can be reduced by ~8% when 95% RO recovery is achieved via the proposed system. Due to the need for increased NaCl salt for regeneration of resins in the proposed system, the environmental impacts increased for metal depletion and ionizing radiation impact categories, unlike the other impact categories. The GHG emissions could be reduced by ~10% (after accounting for 10%-30% probability) for 95% RO recovery with the reduction from the reduced consumption of inputs. Similarly, the life cycle water depletion impacts can be reduced by ~10% (after accounting for 30%-65% reduction probability) from the current 1.75kg water depletion per kg of BFW produced. Water Footprint Assessment (WFA) as per the Ridoutt & Pfister method shows that when accounted for local water stress, during the worst month, the blue water footprint increases from 1.75kg/kg BFW to 63.9kg/kg BFW, in addition to ~0.08kg/kg BFW greywater footprint.</p><p> The social assessment shows mixed results with lower employment, employee development, corporate philanthropy, environmental "protect" spend and R&D spend due to reduced overall consumptions for the 95% recovery option. The other social impact categories were improved for 95% recovery. The overall cost (estimated as the sum of the internally normalized social costs) were 3.0 units with up to 35% reduction potential.</p><p> The results of the case study show that IX feed softening has potential to not only reduce the environmental and social costs, but also meet the financial constraints. Also, this highlights that an integrated sustainability assessment method that evaluates and combines all three aspects of sustainability - environment, social and economic - could be developed. The proposed method as presented needs further development. Among other things, the lack of availability of robust social inventory database significantly hinders the development and adoption such integrated methods. The application of the method to additional case studies would be a good next step.</p><p> This exercise has highlighted that the value and benefits of overall cost estimates are beyond those of policy making by the regulatory agencies. Sustainability minded companies could benefit from having environmental and social goals along with the financial targets as they understand the risks from inadequate performances in any of these aspects. However, these goals are typically on a gate-to-gate basis and independent of each other; thereby, creating the potential for shifting burdens in the value chain and not obtaining the full benefits of risk mitigation. The assessment using the overall cost approach at life cycle basis is essential for industry in not only risk mitigation, but also opportunity identification at an early stage.</p>
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Global and regional assessments of unsustainable groundwater use in irrigated agricultureGrogan, Danielle Sarah 12 July 2016 (has links)
<p> Groundwater is an essential input to agriculture world-wide, but it is clear that current rates of groundwater use are unsustainable in the long term. This dissertation assesses both current use of groundwater for country- to global-scale agriculture, and looks at the future of groundwater. The focus is on 1) quantifying food directly produced as a result of groundwater use across spatially-varying agricultural systems, 2) projecting future groundwater demands with consideration of climate change and human decision-making, and 3) understanding the system dynamics of groundwater re-use through surface water systems. All three are addressed using a process-based model designed to simulate both natural and human-impacted water systems. </p><p> Irrigation can significantly increase crop production. Chapter 1 combines a hydrology model (WBM) with a crop model to quantify current crop production that is directly attributed to groundwater irrigation in China. Unsustainably-sourced groundwater — defined as groundwater extracted in excess of recharge — accounted for a quarter of China’s crop production, and had significant spatial variability. Climate variability and groundwater demand magnified one another in hot and dry years, causing increased irrigation demand at the same time as limited surface water supplies. </p><p> Human decisions about water resource management can impact both the demand and sustainability of groundwater use. Chapter 2 takes an interdisciplinary approach to projecting India’s future (to 2050) groundwater demands, combining hydrology and econometric modeling. The econometric model projects how humans make decisions to expand or contract the irrigated land area of crops in response to climate change. Even in areas with precipitation increases, human decisions to expand irrigated areas led to increasing demands for groundwater. We additionally assessed the potential impact of a large water infrastructure project to alleviate groundwater demands in India, and found that maximum alleviation (up to 16%) was dependent upon the storage volume and location of new reservoirs. </p><p> One proposed method for reducing the world’s demand for groundwater is to increase the efficiency of agricultural water use. However, these same inefficiencies cause a portion of extracted groundwater to enter surface water systems; it can then be reused, creating a complex system in which groundwater demand does not linearly decline with increased water use efficiency. Chapter 3 quantifies the amount of groundwater that enters surface water systems, the number of times this water is reused for agriculture, and the minimum amount of groundwater required by current agricultural systems in the hypothetical scenario of perfect irrigation efficiency.</p>
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Assessment of a Mycorrhizal Fungi Application to Treat Stormwater in an Urban BioswaleMelville, Alaina Diane 02 August 2016 (has links)
<p> 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<sup> ®</sup> 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.</p><p> These results show that the application of PermaMatrix<sup>®</sup> 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. </p>
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Analysis of Managerial Decision-Making within Florida's Total Maximum Daily Load ProgramBarthle, Justin 30 November 2016 (has links)
<p> Water quality has evolved legislatively from protection of navigation routes and quantity of sources to more emphasis on impairments on water quality for surface and groundwater sources. Nonpoint or diffuse sources of impairments represents a major challenge for management due to the complexity of its sources and difficulty in tracking.</p><p> The most cited sections on public policy analysis focuses on the overall process agencies employ to understand the results the program yields. Often overlooked are finer details and mechanisms, such as decision-making and priority setting, which have a great impact on the overall process. To investigate these factors, we need to analyze the decision-making process used by managers.</p><p> This study focuses on using information from those with direct involvement in the establishment and implementation of the Total Maximum Daily Load program for the state of Florida. This study used decision-making analysis models from Rational-Decision-Making and Multi-Criteria Decision Analysis concepts to construct questionnaires that looks to develop priorities as seen by managers’ preferences for several presented options. This methodology allowed us to structure the viewpoints and processes water quality managers use to breakdown decisions.</p><p> The analyzed results show water quality managers prefer strong management options, involvement from stakeholders with scientific knowledge, and data collected from the source or point of impact. Interestingly, opinions in the group show that urban best management practices are considered more effective than their agriculture counterparts with a disfavor for volunteer derived data.</p><p> Ultimately, the survey highlights the need for more robust enforcement and reliable measurement of non-point source of impairments. Continued public outreach and education, especially through workshops, are denoted as important tasks to completing successful TMDLs and should be expanded and strengthened by both the Florida Department of Environmental Protection and its boundary programs.</p>
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Critical review of us environmental protection agency numerical nutrient criteria with respect to culturally significant waters as a designated useCowan Watts, Cara Ailene 21 October 2016 (has links)
<p> The Cherokee Nation, a Federally-recognized Tribal government in Northeastern Oklahoma lacks Tribal water quality standards for numerical nutrient standards based on baseline conditions in the Cherokee Nation. Lotic waters are of special significance in Cherokee Nation culture and ceremonies. Three water quality standard priorities within the Tribe include defining Culturally Significant Waters as a designated use, identifying Culturally Significant Waterbodies and determining applicable numerical nutrient standards. Culturally Significant Water as a designated use was defined based on community surveys. Twelve rivers and streams were identified as a portion of the Culturally Significant Waters of the Cherokee Nation based on a tribal community survey using a Use Attainability Analysis. To address excess nutrients in the Cherokee Nation, a total phosphorus numerical nutrient criterion was determined using data for Culturally Significant Water bodies, literature guidance and the US Environmental Protection Agency recommended nutrient criteria process for the respective Aggregate Nutrient Ecoregion. The Oklahoma Scenic Rivers criterion of 0.037 mg/L total phosphorus for a 90-day geometric mean was evaluated and determined not to be protective of Cherokee Nation’s Culturally Significant Waters. A total phosphorus criterion of 0.016 mg/L was recommended to protect Cherokee Nation Culturally Significant Waters from benthic algae greater than 100 mg/m<sup>2</sup> Chlorophyll <i>a.</i></p>
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Optimized Reservoir Management for Downstream Environmental PurposesAdams, Lauren 16 March 2019 (has links)
<p> In regulated rivers, reservoir operation decisions largely determine downstream river temperature and flow. Computational methods can minimize the risk and uncertainty of making regrettable environmental release decisions and aid operations planning and performance prediction. Mathematical modeling in particular can optimize the timing and magnitude of reservoir release decisions for downstream benefit while accounting for seasonal uncertainty, water storage impact, and competing water demands. This dissertation uses optimization and modeling techniques, modifying traditional optimization modeling to include temporal correlation in outcome variables and incorporating long-term planning and risk management into prescribed reservoir operations. The proposed method is implemented in one case, a) with a state variable that tracks outcome benefits over time (fish population size) and, in another case, b) with a maximin stochastic dynamic program solution algorithm that maximizes net operational benefit and minimizes worst-case outcomes (for cold water habitat delivery). This method is particularly useful for environmental flow management, when the water quality and quantity of the river and reservoir in one time step affect the quantity and quality in the reservoir and the river for later periods. Better solutions with these methods internalize risk and hedge releases at the beginning of an operating season to maximize downstream benefit and reduce the probability of catastrophe for the season and future years. Maximizing the minimum cold-water habitat area over months of a season or multiple years, or maximizing a river indicator variable explicitly, could likely help, for example, maximize an out-migrating salmon smolt population downstream. The method is demonstrated with a case study optimizing environmental releases from Folsom Dam and another optimizing temperature management from Shasta Dam in northern California. These results inform general rules for environmental flow management and temperature management of reservoirs, with specific policy recommendations for both Folsom and Shasta reservoirs. In both cases, the added value from employing hedging rules help reservoir operations minimize the risk of environmental catastrophe and conserve storage both within an operating season and across years.</p><p>
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Amphibians as Wetland Restoration Indicators on Wetlands Reserve Program Sites in Lower Grand River Basin, MissouriMengel, Doreen C. 09 March 2019 (has links)
<p> Globally, amphibians have suffered dramatic population declines in the past twenty years with habitat destruction implicated as the primary threat. The Natural Resources Conservation Service’s Wetlands Reserve Program (WRP) restores wetlands on marginal agricultural land and is a means to restore the spatio-temporal wetland habitat required by amphibians to prevent, reverse, or stabilize declining population trends. The goal of WRP is “to achieve the greatest wetland functions and values, along with optimum wildlife habitat, on every acre enrolled in the program.” Functions and values are defined as the hydrological and biological characteristics of wetlands. A key unanswered question is to what extent is this goal being achieved? Amphibians enable quantifying the WRP goal due to their life-history requirements and explicit incorporation of their habitat needs into WRP plans. My research goal was to determine if hydrological and biological wetland characteristics had been restored to WRP sites in the Lower Grand River basin, north-central Missouri, based on distribution, recruitment success, and relative species richness estimates for members of a regional species pool. I identified three design strategies applied to WRP sites over time: walk-away, maximize hydrology, and naturalistic; the latter emphasizing restoring process as well as structure; and evaluated if design strategy was a useful covariate for restoration efforts. I encountered 10 amphibian species representing 59% of the regional species pool. Design strategy was not a predictive site-level covariate as sites within all three design strategies had varying hydrological wetland conditions resulting in greater habitat heterogeneity than anticipated on maximize hydrology and walk-away sites and less than anticipated on naturalistic sites. Amphibian detections occurred across all sites resulting in no difference among design strategy as the degree of heterogeneity in habitat conditions at the within site-scale demonstrated that amphibians were responding to ecological conditions that occur at a finer resolution than site. Results, irrespective of design strategy, indicate seven of the detected species or groups were widely- distributed, two were moderately- distributed, and two were sparsely distributed on WRP sites indicating hydrological wetland characteristics have been restored to sites given the moderate- to wide-distribution of species associated with both seasonal and permanent wetlands. Although species were successfully recruiting young into adult populations, only leopard frogs had high estimates of recruitment success whereas the remaining species had moderately high to moderate to low recruitment estimates indicating biological wetland characteristics are somewhat lacking to lacking for these species. Results from the relative species richness assessment indicate that, whereas 74% of the sites provided some degree of wetland habitat for members of the regional species pool over the course of the field season (7 March – 19 September), 52% of the sites lacked suitable habitat conditions during the peak of amphibian breeding and larval development (May through July). Targeting management actions that result in suitable seasonal wetland habitat conditions (shallow, vegetated wetlands that gradually dry by mid-to late-summer) throughout the time needed for species to complete their life history requirements is one method to increase the biological wetland value of restored WRP sites. Results show the value of WRP at conserving and restoring river-floodplain amphibians; however, achieving optimum wildlife habitat on every enrolled acre will be difficult at a site-level scale as habitat requirements, although overlapping, vary widely for the full range of species. Providing for all species in the regional species pool requires sites that transverse both the longitudinal and lateral floodplain gradient. If WRP is to realize its full potential, there must be recognition that optimum wildlife habitat can be defined at multiple spatial and temporal scales that match the landscape setting. Optimum wildlife habitat at a wetland scale is not the same as optimum wildlife habitat at the floodplain scale. The intent of WRP is to convert marginal, flood-prone agricultural lands back into wetlands so enrollment of lands located outside the active floodplain may be impracticable or unrealistic. Whereas attaining optimum wildlife habitat on every acre enrolled in the program may not be an achievable objective, providing optimum wildlife habitat for members of a regional species pool within an appropriately defined geography that includes both a longitudinal and lateral gradient represents an objective that is both desirable and attainable.</p><p>
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Aquifer Mergence Zones of the East Newport Mesa, Orange County, CA| A Geochemical Investigation of Hydrogeologic Structure and Groundwater FlowNeel, Brendan R. 25 April 2019 (has links)
<p> Aquifer mergence zones are erosional unconformities that hydraulically join interlaying aquifers. In the East Newport Mesa in Orange County, Southern California, aquifer mergence zones may provide a pathway for potentially impaired low-quality groundwater of the shallow, semi-perched aquifer to migrate into the underlying regional, potable, confined aquifers. Major ion and stable isotope results imply that vertical mixing is occurring locally between the discrete shallow and deep groundwater endmembers. Vertical mixing is suggested by anomalously young radiocarbon age-dates of deep groundwater units. Radon-222 results show that shallow groundwater is discharging from the mesa, and is also actively intruded by surface water. Mixing of shallow and deep waters at these mergence zones may pose a threat to the deeper regional aquifer system. </p><p>
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Texas Water Resources: Vulnerability from ContaminantsDwivedi, Dipankar 14 March 2013 (has links)
Numerical models of flow and transport are commonly applied for the sustainable management of water resources and for the selection of appropriate remediation techniques. However, these numerical models are not always accurate due to uncertain parameters and the disparity of scales across which observations are made, hydrological processes occur, and modeling is conducted. The modeling framework becomes further complex because hydrologic processes are coupled with chemical and biological processes. This dissertation focuses on the most widespread contaminants of surface and ground water, which are E. coli and nitrate, respectively. Therefore, this research investigates the linkages between bio-chemical and hydrologic processes for E. coli transport, explores the spatio-temporal variability of nitrate, quantifies uncertainty, and develops models for both E. coli and nitrate transport that better characterize these biogeochemical linkages.
A probabilistic framework in the form of Bayesian Neural Networks (BNN) was used to estimate E. coli loads in surface streams and was compared with a conventional model LOADEST. This probabilistic framework is crucial when water quality data are scarce, and most models require a large number of mechanistic parameters to estimate E. coli concentrations. Results indicate that BNN provides better characterization of E. coli at higher loadings. Results also provide the physical, chemical, and biological factors that are critical in the estimation of E. coli concentrations in Plum Creek, Texas.
To explore model parameters that control the transport of E. coli in the groundwater (GW) and surface water systems, research was conducted in Lake Granbury, Texas. Results highlight the importance of flow regimes and seasonal variability on E. coli transport.
To explore the spatio-temporal variability of nitrate across the Trinity and Ogallala aquifers in Texas, an entropy-based method and a numerical study were employed. Results indicate that the overall mean nitrate-N has declined from 1940 to 2008 in the Trinity Aquifer as opposed to an increase in the Ogallala Aquifer. The numerical study results demonstrate the effect of different factors like GW pumping, flow parameters, hydrogeology of the site at multiple spatial scales.
To quantify the uncertainty of nitrate transport in GW, an ensemble Kalman filter was used in combination with the MODFLOW-MT3DMS models. Results indicate that the EnKF notably improves the estimation of nitrate-N concentrations in GW.
A conceptual modeling framework with deterministic physical processes and stochastic bio-chemical processes was devised to independently model E. coli and nitrate transport in the subsurface. Results indicate that model structural uncertainty provides useful insights to modeling E. coli and nitrate transport.
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