Water resources in Florida have been severely degraded by eutrophic conditions, resulting toxic algae blooms, which negatively affect health and tourism. Eutrophication, or excessive amount of phosphorus (P) and nitrogen (N) in water, overstimulates the production of aquatic plants, depletes dissolved oxygen, and deteriorates the aquatic environment. However, phosphorus is a non-renewable resource essential for all living organisms. In fact, more than half of the total demand for P globally is to supply the food industry, which has concerningly accelerated the depletion rates of phosphate reserves. In many wastewater treatment plants (WWTPs), the enhanced biological phosphorus removal (EBPR) approach has been employed to achieve high phosphorus removals from wastewater through phosphate-accumulating organisms (PAOs). However, during either anaerobic or aerobic digestion of EBPR sludge, stored polyphosphates are released and carried into the sidestream, which is typically returned to the headworks of the main treatment facility, thereby recycling phosphorus back into the system. This treatment train is highly inefficient because nutrients rather are recirculated rather than recovered. Struvite (MgNH4PO4•6H2O) is precipitated in oversaturated aqueous solutions with equal molar concentrations of magnesium, ammonium, and phosphate. The controlled crystallization of struvite may be applied to remove phosphorus and some ammonium from sidestreams, which is the liquid portion of the digester effluent. Struvite can be employed as a sustainable slow-release fertilizer due to its low solubility in water. This offers the opportunity of marketing the struvite produced under controlled conditions and creating a revenue for the utility. The specific research objectives of this thesis are (1) to investigate different possible operating conditions under which anaerobically digested sludge from EBPR facilities might be treated through struvite precipitation; (2) to quantify the removal of N and P from sidestreams from anaerobically digested EBPR sludge via struvite precipitation and assess the composition of the precipitate obtained; and (3) to generate a cost analysis to assess the trade-offs between the capital and operation and maintenance (O&M) costs of struvite production and the benefits such as reduced chemical use and production of a slow-release fertilizer. The main parameters affecting struvite precipitation are the Mg2+ to PO43- molar ratio, pH, temperature, mixing speed, hydraulic retention time (HRT), and the seed quantity added to promote nucleation. Different operating conditions within these parameters were batch-tested as part of this study using sidestream from the pilot-scale anaerobic digester (AD) fed from Falkenburg Advanced Wastewater Treatment Plant (FAWWTP) EBPR sludge. Additionally, the effect of temperature and pH were investigated using Visual MINTEQ simulations. Analysis of Variance (ANOVA) was employed to investigate the variance within the removals from the centrate obtained for phosphate, ammonium, magnesium, and calcium. The chemical composition of the solids collected after employing the selected operating conditions was analyzed by powder X-ray diffraction (PXRD). The results for the batch tests performed as part of this thesis were quantified in terms of the removals of phosphate, ammonium, magnesium, and calcium from the centrate. The greatest amount of phosphate removal was achieved by operating the struvite reactor at 4.0 mmol of Mg2+ per mmole of PO43-. The other molar ratios tested were 1.0, 2.0, and 3.0. Visual inspection of the data showed significant variability in removals of ammonium, calcium, and magnesium, which are likely to be correlated with the highly variable influent concentrations into the struvite reactor. In this case, ANOVA will require larger data sets to accurately analyze variance in the results. The statistical results given by ANOVA for the pH suggests that the main species to contribute with struvite being precipitated are statistically stable within the tested pH values of 8.5, 9.0, and 9.5. The results obtained by the simulation using Visual MINTEQ indicated that maximum saturation as function of pH takes place at a pH between 9.5 and 10.0. The ANOVA for the mixing speed showed that significant amounts of ammonium were removed at higher mixing speeds. This is likely due ammonium being volatilized, which is enhanced by turbulence. Magnesium and phosphate showed lower removals at higher mixing speeds, suggesting that too high mixing speeds will promote struvite seed dissolution. ANOVA identified NH4+ and Ca2+ as the species significantly impacted by modifying the HRT from 8 to 20 minutes. This suggests that prolonged HRT promotes inorganic nitrogen species to volatilize. It is likely that at higher HRT, tricalcium phosphates (TCP) or other favored calcium species coprecipitated together with struvite. Regarding the added struvite seed for nucleation, the greatest removals of ammonium, magnesium, and, phosphate were observed when 1g/L of struvite seed was added. The results also indicated that adding 5 and 10 g/L was an excessive amount of seed, which ended up contributing significantly to more nutrients into the centrate rather than precipitating them. The results also suggested that the struvite crystals formed in the sidestream by secondary nucleation, since removals close to zero were reached after adding no seed. The optimum temperature identified by the simulation in Visual MINTEQ was 21°C. Operating the struvite reactor under the optimal conditions identified in the batch tests, resulted in an average of 99% total P (TP) and 17% total N (TN) removals. The precipitate molar composition for [Mg2+:NH4+:PO43-] was equal to [2:2:1] based on the concentrations that disappeared from the aqueous solution, suggesting that other minerals coprecipitated with struvite. Visual MINTEQ predicted that together with struvite, CaHPO4 and CaHPO4•2H2O will also precipitate under the tested conditions. However, given the obtained ratio it is likely that other unpredicted species by Visual MINTEQ, such as magnesium carbonates or magnesium hydroxide coprecipitated with struvite. PXRD analysis also revealed that the sample was likely contaminated struvite, although the specific contaminants were not identified. A cost analysis was performed to distinguish the economic feasibility of incorporating a struvite harvesting system to treat the anaerobically digested sidestream from the Biosolids Management Facility (BMF) within the Northwest Regional Water Reclamation Facility (NWRWRF). Three different scenarios were evaluated; in Scenario (1) Ostara® Nutrient Recovery Technologies Inc. (Ostara®) evaluated the production of struvite from anaerobically digested EBPR sidestream using a fluidized reactor. In Scenario (2), Ostara® evaluated the production of struvite in a fluidized bed reactor by employing Waste Activated Sludge Stripping to Remove Internal Phosphorus (WASSTRIP™) in a mixture of post-anaerobic digestion centrate and pre-digester thickener liquor. Scenario (3) was addressed by Schwing Bioset Inc. (SBI) for a continuously-stirred reactor followed by a struvite harvesting system. Scenario (2) offers the highest TP and TN recoveries through WASSTRIP™ release due to the additional mass of phosphorus that is sent to the phosphorus recovery process. Therefore, although Scenario (2) has the highest total capital costs ($5M) it also has the shortest payback period (18 years). Scenarios (1) and Scenario (3) have similar payback periods (22-23 years) but very different total capital costs. The annual savings by producing struvite in Scenario (3) is $40K, which is about 30% less than producing struvite in Scenario (1). This is probably because the only savings considered under Scenario (3) were the lower alum usage and the fertilizer revenue; however, the savings by producing class A biosolids, were not accounted for. Consequently, the reduced total capital cost of $960K and the annual payment amount per interest period close to $80K, positioned Scenario (3) as the more feasible one, considering 20 years as the expected life of the asset at a 5% interest rate.

Water is the root of life and the engine that drives agriculture, industry, economy and services. The demand for water often necessitates desalination, particularly in arid coastal environments where there are several desalination technologies in use today such as Multi-Effect Distillation (MED) and Reverse Osmosis (RO). The key utility requirement for technologies such as desalination and population in general include energy in one form or another. Therefore, desalination and co-generation are often integrated. Another key utility is electricity which is generated from either renewable or non-renewable sources. The demands for water and electricity change over time and are subject to uncertainty. In this dissertation, a country-wide large-scale energy and water cogeneration planning model for Kuwait was proposed and solved. Five different plant technologies where the planning horizon used was set to 37 years starting in year 2014 and until 2050. A Mixed Integer Mathematical programming model was proposed and formulated using General Algebraic Modeling System (GAMS), the resulting model was solved using the CPLEX solver engine. In this research obtained detailed data on the consumption on water and energy in Kuwait and performed time series analysis of the population growth and individual behavior of water and energy consumption and novel method to represent cogeneration plants was implemented in the proposed mathematical programming model. ix A modeling framework that involves a data spreadsheet and a proprietary model was implemented. The data spreadsheet and the model were formulated as a template that can receive data from different applications. In addition, automation using Visual Basic for Application (VBA) was made to the data spreadsheets such that the data is sent to the model template, Gams-Cylix, and are written back to the spreadsheet. An analysis was made between oil-based plants, natural gas (NG) plants, and solar-based plants for co-generation. It was found that for water production solar-based plants can supply 50 percent or more of the demand during after period 2020 and after implementation and for electric power generation solar plants are limited. The results indicate the preferred technology for energy generation was NG-RO. With the implementation of solar based plants the electric power load is distributed among the technologies. NG-RO plants are more scalable and therefore were expanded to cope with the future demand. The percentage of the electric power supplied by solar plant was below 35 percent across the planning horizon. By the end of the planning horizon the percentage of electric power supplied by solar base plants was nearly 20 percent. Near 70 percent of the electric power was supplied by NG RO by period 2050. Other technologies had a representation of less than 10 percent by the end of the planning horizon.

Nonpoint source nutrient pollution is diffuse pollution lacking discrete origin and conveyance. This thesis synthesizes and critically reviews research on residential nitrogen and phosphorus loss to stormwater runoff and leaching. The evaluation pulls from research covering influential socio-demographic indicators, such as use of lawn maintenance services and homeowner fertilizer practices. The extent to which such social and economic factors may influence the prevalence and fate of diffuse nutrients in stormwater runoff from residential areas has not been adequately established. Understanding the source and influencing factors of diffuse nutrient pollution is important in order to effectively protect surface and groundwater resources. Research based on sampling campaigns of catchments, sampling of controlled turf systems and models of residential catchments were compiled for this review. Based on the compilation reviewed for this thesis, there are wide differences in approaches researchers have taken to attempt to quantify and understand diffuse nutrient pollution from residential and urban areas. There is not consistency in the chemical nitrogen or phosphorus species evaluated or in reported measurements (i.e. concentration vs. loading vs. yield). This review revealed several important knowledge gaps. Determination of correlation between residential system nutrient loss to the environment and social factors, demographic characteristics, local fertilizer ordinances or nutrient management education programs has not been substantiated. More exploration of nutrient leaching from different soil types and turf grass species is needed to develop a complete understanding of nutrient loss from turf grass systems. Further, other specific management practices such as leaving grass clippings on lawns has not been studied in depth for a variety of soil types and grass species. There is room for improvement in future research and additional studies are needed to guide future policy and implementation of best management practices. Based on these and other findings, I recommend a concerted effort to standardize a portion of the reporting details of future stormwater research and for reevaluation of nutrient/fertilizer education efforts.

Water and sanitation (WatSan) development projects impact both natural systems and societal structures where they are placed. A complex process of development, including inter-governmental policies, aid agencies, personal relationships, and community politics enhance and constrain the efficacy of these projects. This study presents the many ways in which the WatSan development process has unintended and unexpected returns for certain community groups. Using a political ecology framework, I look at power structures, perceived and projected environmental impacts, multiple stakeholders, and individual discourses to critique how the right to water and sanitation is implemented in a specific community context. This project advances anthropological thought by showing a praxis-based study that links theory, on-the-ground, ethnographic experience, policy recommendations, and theoretical injections which relate to a variety of audiences, both within and outside of the academy. The project is conducted in two main field locations--La Paz and Sapecho, Bolivia. I employ a mixed-method approach, including interviews with development professionals and community members, a survey of water and sanitation users, focus groups with particularly impacted groups (e.g. water committees, students, and women), and various mapping techniques (GPS mapping, community-led) to address the space and place within which this project was realized. I give specific focus to sewage collection and wastewater treatment, two elements of the WatSan system that are distinctive in this rural developing-country context. WatSan development is not just infrastructure placement. It is a full process, a relationship. It comprises individual conversations, days of work, salaries, payment schedules, labor, expertise, and ongoing management practices. Individual perceptions of infrastructure efficacy, personal benefit, and best practices (both culturally and technologically) impact the long-term effectiveness of a project. Major tensions arise post-implementation: between community and aid agency, conservation and use, labor and upkeep, and sanitation and potable water. There are multiple influences and positions subsumed in this process. The study's political ecology approach, combined with foci on human rights, critical development, and water and culture, provides critical insights into the relationship between social and resource-based (water infrastructure) change. It looks at the ways in which the benefits and risks of a WatSan system are stratified, gendered, and power-laden. It further looks at the potential positive and negative outcomes of the system--all with an enviro-social focus. I look at how social and ecological relationships are tethered together (mutually constituted), how they are influenced by several levels of governance and policy. The experience of Sapecho shows how changes to WatSan environments can provide new water and sanitation access but in some cases, further engrain and exacerbate social inequalities. Provision of fresh water, sewage collection, and wastewater treatment infrastructure is not value-free--but it is necessary. This work tries to answer one small part of the question of how the right to water and sanitation can be best implemented in real-world situations.

It has been reported that globally we have achieved Millennium Development Goal (MDG) Target 7C, to halve the proportion of the population without access to safe drinking water; however, there is a major flaw with this statement. While Target 7C calls for access to `safe' drinking water, what is actually being measured and reported is access to an `improved' water source. The World Health Organization (WHO) maintains that they must use this proxy measure because the methods for water quality testing are too expensive and logistically complicated, but by doing so, they may be over reporting safe water coverage. This was shown to be true in Tamatave, Madagascar, where thermotolerant coliforms were detected in water from a type of `improved' source, the Pitcher Pump system. This research looked at several parameters - Pitcher Pump system depth, sampling neighborhood, requirement of pump priming, frequency that the system was repaired, distance from on-site sanitation, and number of users - to see if they were influencing water quality. Of all the parameters tested, only priming was found to be significantly associated with the levels of thermotolerant coliforms detected (Fisher exact test p = 0.03). Using a Mann-Whitney U test, it was shown that the median thermotolerant coliform concentration was significantly higher in primed wells (41.3 cfu/100 ml) than unprimed wells (3.5) (p = 0.01 cfu/100 ml). A pilot study was conducted to look at only the effect of depth and to determine if a depth could be identified that could provide safe drinking water. The result of the pilot study showed that, while thermotolerant coliform concentration did decrease with increasing depth, even at the deepest well of 9.4 m, levels were still above 100 cfu/100 ml. Additional research was conducted to investigate the performance and cost of three test kits for both total coliform and Escherichia coli quantification for water quality analysis in developing countries. IDEXX Colilert Quanti-trays[reg] (Colilert), Micrology Laboratories Coliscan[reg] Membrane Filtration tests (Coliscan MF) and a modified method for 3-M PetrifilmTM Coliform/E. coli plates (modified 3-M) were compared with standard membrane filtration (standard MF) methods under a range of incubation temperature conditions (22.0, 35.0 and 44.5[deg]C). Each test method was also performed by inexperienced volunteers, with the results compared to those of an experienced technician. At non-standard temperatures, Coliscan MF proved to be the most accurate when compared to standard methods, with a significant difference with only total coliforms at 44.5[deg]C. Modified 3-M had the poorest correlation with standard MF over the range of temperatures tested, with significant differences noted for all the temperatures except for E. coli at 44.5[deg]C. Inexperienced university volunteers found Colilert easiest to use, but Coliscan MF produced E. coli results that were most similar to the experts. Coliscan MF was found to have the overall best performance and lowest cost in this study; however, it did produce high numbers of false positive results.

Since 1989, the co-riparian States of Georgia, Florida and Alabama have been locked in an overt and institutionalized conflict to secure access to the waters of the Apalachicola-Chattahoochee-Flint (ACF) River Basin. In 1997, in an effort to end this interstate conflict which had earned the reputation as the longest water conflict in U.S. history, public officials at the federal and state scales agreed to suspend all pending litigation against one another and concurrently deployed a dispute resolution mechanism, known as `compact negotiations,' in the hope of equitably allocating the waters of the ACF Basin. Despite proclamations by public officials, exclaiming their commitment to the process of compact negotiations and their desire to see an end to the lingering conflict, 2014 marks the 25th anniversary of the bitter conflict over the ACF waters and a sustainable resolution has not yet been achieved. Against this background, this study provides an in-depth empirical explanation for why multiple efforts to resolve the ACF conflict have been unsuccessful and largely counterproductive. Using data collected from in-depth interviews with elite stakeholders and archival data parsed from executive agencies, bureaucratic reports and media sources, this study demonstrates that Georgia's strategic efforts to (a) rescale water management authority in the basin along neoliberal lines and (b) spatiotemporally displace demand- and supply-side management policies, have allowed Georgia and metropolitan Atlanta to achieve water security through a process of accumulation by dispossession. Finally, this study shows that Georgia and Atlanta's water security has compromised the authority of federal agencies to manage interstate waters, exposed the inability of the three riparian states to reach equitable compromise, and demonstrated the Court's express complicity in (re)producing uneven development in the American South.

A large part of the environmental restoration required by the Comprehensive Everglades Restoration Plan calls for more water-storage on lands south of Lake Okeechobee in order to restore the natural water flows of the Everglades watershed. The Everglades Agricultural Area (EAA) can be used for increased water storage in order to relieve coastal estuaries of excess water in the rainy season. This water storage can deliver additional ecosystem services of soil retention and reduced CO2 emissions that could compensate farmers for the cost of water storage by increasing long term farm profitability. The goals of this study were 1) to quantify the environmental and economic trade-offs of different water storage scenarios using water-tolerant sugarcane cultivars, and 2) to quantify the amount of water storage possible in the EAA under different water storage scenarios. A mathematical model was developed to calculate soil depth, soil subsidence, depth to the water table, sugarcane production, farm return, water storage and carbon loss for three different sugarcane cultivars with different water-tolerances. A GIS tool is also developed to estimate the amount of water storage possible in the EAA. The study found that even though water-tolerant sugarcane cultivars experience higher yields and net returns than non-water-tolerant cultivars the water storage costs with these water tolerant cultivars was greater. Raising water tables on farm lands did have the environmental benefits of reduced soil subsidence, extended farm life and increased years of water storage. However total CO2 emissions rise from 14 to 136%. Results of the GIS analysis revealed that water storage capacity for a DWT of 61 cm is 1,404,562 ac-ft, 1,417,400 ac-ft for DWT 45 cm and 1,474,692 ac-ft for DWT 20 cm. The GIS analysis was also able to identify flow ways that could possibly carry water south from Lake Okeechobee and ultimately to the WCAs south of the EAA. These results show that raising water tables in the EAA to deliver the ecosystem service of expanded water storage is overall more costly, but yearly costs are very low. Therefore water storage on farmlands is an affordable interim method of water storage.

<p>The aim of this study was to evaluate the impact of community involvement on management of water tanks in the Arkavathi sub-basin in the state of Karnataka, South India. Water management was analysed from a socio-environmental perspective, with emphasis on village-level stakeholders’ roles and perceived responsibility. The efficiency of community participation was investigated by comparing two villages having undergone the same World Bank launched program to restore water bodies traditionally used to sustain the livelihood of the rural population. In one village there was a resistance towards how the implementation of the tank rejuvenation project had been performed, in the other there was no local involvement.</p><p>A minor field study was conducted by visiting the two villages. Qualitative interviews were held with village-level stakeholders of three age groups, to analyse changes over time in knowledge and attitudes. Additionally, ocular observation and photo documentation were made of the study areas. Some informal interviews were carried out with members of an external non-governmental organisation and locals in the study villages. The collected data were analysed by comparing the results for the two villages, as well as the results of the different age groups and genders.</p><p>There were significant differences in awareness and sense of responsibility, but not knowledge, between the two villages. In the village with a community involvement resisting the governmental scheme for tank renovation, this involvement had proved to be of some advantage to the local community. Contrary to the guidelines, the governmental implementation of the water management strategy did not include local stakeholders’ participation, nor were the tanks restored. Overall, the villagers considered the tank management to be the responsibility of external authorities. There were generally no significant differences between the age groups or men and women, though there were indications of a lower level of knowledge and awareness in women. Absence of effective institutions for water management on all levels as well as difficulties in mainatining efficient village level leadership for community participation are factors causing a major gap between planning and implementation.</p>

Beaver Creek, located in North Knox County, Tennessee, is on the Tennessee 303(d) list as an impaired stream that fails to meet its designated uses. Phosphorus (P) is one of the major pollutants of the stream. High P levels within surface water can lead to water quality problems including low dissolved oxygen, overgrowth of algae, and eutrophication. Two sources, pasture grazing areas and major municipal point sources, have been identified as important contributors of P to Beaver Creek. The objective of this study was to analyze the total P and Mehlich III extractable P concentrations of sediments in Beaver Creek and determine if a P signal could be identified in sediments collected along two stream reaches, less than 1500 m long, adjacent to a cattle farm and a wastewater treatment plant (WWTP). Eight sites were sampled within Beaver Creek, divided between two locations. At each sample location, four sample sites were selected. One site, the “control” was upstream of the P input. One, the “source,” was immediately downstream of the P input. Two additional sites, one within 200 m and the second within 400 m downstream of the source, were selected at each location. Nine sediment samples were collected at each sample site. Sediments were analyzed for total P (SW-3050B) and Mehlich III extractable P. ANOVA was run between the sites at each location and t-tests were completed to look for significant differences and a downstream signal. At the cattle farm, P concentrations of sediments at the downstream 2 site were significantly higher than sediment P concentrations at the three other sites. However, unexpectedly high results from the control sample site, combined with unexpectedly low results from the source sample site made it difficult to assess whether the cattle farm was affecting sediment P in Beaver Creek. At the WWTP, the sediment P near the outfall was significantly higher than sediment P at the control. Sediments at the downstream 1 site had significantly higher P concentrations than sediments at the other three sites, indicating that the WWTP may be affecting sediment P in Beaver Creek. This study supports the hypothesis that increased P concentrations could be attributable to P inputs from a WWTP. However, further study is needed about the effects that pastures have on sediment P concentrations within Beaver Creek.

<p>Coastal eutrophication is a complex process that is caused largely by anthropogenic nutrient enrichment. Estuaries are particularly susceptible to nutrient impairment, owing to their intimate connection with the contributing watersheds. Estuaries experiencing accelerating eutrophication are subject to a loss of key ecological functions and services. This doctoral dissertation presents the development and implementation of an integrated approach toward assessing the water quality in the Neuse Estuary following the implementation of the total maximum daily load (TMDL) program in the Neuse River basin. In order to accomplish this task, I have developed a series of water quality models and modeling strategies that can be effectively used in assessing nutrient based eutrophication. Two watershed-level nutrient loading models that operate on a different temporal scale are developed and used to quantify nitrogen loading to the Neuse Estuary over time. The models are used to probabilistically assess the success of the adopted mitigation measures in achieving the 30 % load reduction goal stipulated by the TMDL. Additionally, a novel structure learning approach is adopted to develop a Bayesian Network (BN) model that describes chlorophyll dynamics in the Upper Neuse Estuary. The developed BN model is compared to pre-TMDL models to assess any changes in the role that nutrient loading and physical forcings play in modulating chlorophyll levels in that section of the estuary. Finally, a set of empirical models are developed to assess the water quality monitoring program in the estuary, while also exploring the possibility of incorporating remotely sensed satellite data in an effort to augment the existing in-situ monitoring programs.</p> / Dissertation