<p> Empowering citizens to comprehend complex environmental issues affecting their daily lives is essential to sustaining a healthy and informed public. The work of many environmental nongovernmental organizations (ENGOs) and institutions of higher education (IHEs) center around helping their stakeholders become informed of, and in turn, better understand complex environmental problems. However, providing individual stakeholders with knowledge about environmental issues that is easily accessible and understandable represents a recurring challenge in today's society. As a result, a gap continues to exist between that which is known about environmental problems and the public's awareness and understanding of those issues. Arsenic contamination of drinking water from privately owned groundwater wells in rural areas of the southwest the United States is one such environmental issue, which is the focus of this research project. </p><p> Results from this study demonstrate that an Internet-based GIS application represents a promising tool for informing stakeholders of selected water quality issues and helping stakeholders comprehend the scope of arsenic found in drinking water in rural areas. Specifically, findings from this research suggest that the interactive environment of an Internet GIS is an easy to use technology that facilitates the visualization of arsenic water quality impairment in an accessible format for stakeholders. Feedback from ENGO and IHE professionals (who were the target population in this study) indicated that an Internet GIS application, such as the one used in this project, represents one method to inform stakeholders of drinking water quality issues. This, in turn, contributes to reducing the gap between known scientific information about environmental issues and stakeholder knowledge of the facts and consequences associated with those concerns. </p><p> Results from this study inform an important initial step in reducing the knowledge gap (i.e., determining ENGO and IHE professionals' perspectives about the value of use of an Internet GIS for engaging with public stakeholders), leading to the subsequent task of ensuring that public stakeholders are aware of the opportunities to use Internet GIS to become more informed about water quality issues. To advance the findings from this project, additional research is needed to further clarify best practices that ENGO and IHE professionals may employ to disseminate an easily accessible Internet GIS for water quality from rural, unregulated sources. Additional need exists to gather and compare the perceptions of stakeholders with the perspectives of ENGO and IHE professionals to best clarify the use of Internet GIS as a tool to disseminate unregulated drinking water quality information to rural water users.</p>

The presence and fate of the steroidal estrogens, estrone (E1), 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2), in Ottawa and Cornwall wastewater treatment plants (WWTP's), drinking water, and the river water used as the drinking water source, were identified. Estrogens were extracted using accelerated solvent extraction, gel permeation chromatography and solid phase extraction, and identified using gas chromatography-mass spectrometry and internal C-13 standards. E1, E2 and EE2 concentrations ranged from 1.8 to 370, 24.3 to 66.9 and 0.4 to 9.8 ng L-1, respectively, and were affected by weather variables such as temperature and precipitation, and WWTP parameters such as daily flow and carbonaceous biochemical oxygen demand. Photodegradation rate constants under ultraviolet B radiation for E1 were directly proportional to radiation intensity and sample thickness, and inversely proportional to dissolved organic carbon concentration, but EE2 was remarkably persistent. A luciferase reporter gene assay found estrogenicity in both sewage effluent and UVB-exposed samples of estrogens, contributed by the degradation products of steroidal estrogens. Finally, EE2 persistence was also seen in a time-course experiment in which goldfish were exposed to 25 ng L-1 EE2. A mass-balance model calculated a bioconcentration factor (BCF) for EE2 in fish blood of 1400, whereas measured data revealed a maximum BCF of only 500.

Abstract not available.

Growing populations, urbanization, environmental awareness with resultant regulations and water scarcity have resulted in a search for alternative water sources. Municipal wastewater reclamation and reuse is a necessity in these conditions because it is a water source that is available throughout the year. It can reduce the demand for source water and could be treated at lower costs to the required water quality requirements of the intended use. South Africa especially the Gauteng Province is subjected to the above mentioned stressors but lacks a holistic approach to wastewater reclamation and reuse as a practical and viable solution. Furthermore, the lack of characterization parameters as well as advanced wastewater treatment methods and the viability assessments of the municipal wastewater generated in the South Gauteng catchment, has led to loss of potential water resource in the province. Therefore the current research was initiated as a baseline study to investigate the feasibility of municipal wastewater reclamation and reuse in the South Gauteng catchment. The specific objectives were to 1) assess the worldwide practices of wastewater reuse, 2) apply influent and effluent data analysis and make recommendations on the type of reuse application available for the Southern Gauteng municipal wastewater treatment effluent and to 3) assess the viability of tertiary treatment technologies as best fit options available for different reuse options required for the study area. To achieve the above mentioned objectives a literature review was undertaken to assess worldwide water reuse practices and how they can be used in the study area to utilize the generated wastewater effluent. Influent and effluent data of four wastewater treatment plants (WWTPs) in the Sedibeng district municipality (SDM), three in the Emfuleni local municipality and one in the Midvaal local municipality, was used to assess the viability of water reuse. Available worldwide aggregate, nutrient, ionic and microbiological water reuse standards and criteria for potable, agricultural and industrial use were used to characterize the Sedibeng WWTPs for water reclamation. Wastewater reclamation and reuse is broadly defined as collecting treated or untreated wastewater and using it for a purpose different from what it was used for previously. Recycling, on the other hand, is using water, for the same purpose repeatedly (DWA, 2013a). Water reuse is practiced in countries such as the Western United States, Australia, Singapore, Namibia, Mediterranean countries and Japan for potable use, irrigation and industrial purposes. South Africa, having laid the foundation of wastewater reuse in Namibia, currently practices direct potable reuse (DPR) in the Beaufort West municipality as well as internal water recycling in the power, steel, petrochemical, paper and pulp industry. Water reuse standards and criteria are set based on regional differences of water availability, public health protection, monitoring feasibility, industry types and the reuse purpose. Risk assessment that includes among others a multi-barrier approach, water quality criteria objectives and acceptance determines treatment technology selection. Tertiary treatment technology such as ultrafiltration, reverse osmosis and advanced oxidation processes especially UV/H2O2 are used in water reclamation plants after preliminary treatment of secondary effluent. The four SDM WWTPs effluent, which was over 220 ML/d, the results show, mostly use activated sludge process and have water quality determinants complying with the design criteria for advanced treatment in water reuse. This effluent meets the Namibian Goreangab and Beaufort West Water Reclamation Plant (WRP) multi-barrier influent design criteria for DPR in most aggregate, nutrient and ionic parameters except microbiological parameters. Parameters such as chemical oxygen demand (COD), dissolved solids and ammonia and alkalinity were non-compliant for which this could signify incomplete activated sludge process. This shows the importance of secondary treatment as one of the barriers in the multi barrier approach. Even though membrane treatment of this effluent to improve these parameters and microbiological quality is possible effective secondary treatment as one of the barriers is important to prevent downstream membrane fouling. Depending on this water quality the water will be suitable for indirect potable reuse (IPR) with blending, industrial cooling, heat exchange and dust suppression as recommended uses. Municipal effluent, which could reduce potable water demand, is currently not used in the study area’s power generation and steel making industries Eskom’s Lethabo power station and ArcelorMittal respectively. This is even though, advanced water treatment processes such as reverse osmosis, exist for both organization’s internal wastewater recycling. The reclaimed municipal effluent can be introduced to moderate water quality processes such as cooling systems, heat removal, waste handling and washing in both industries in the study area. Public-private partnerships (PPPs) with water intensive user industries incorporating municipal secondary effluent in current and future infrastructure plans to find viable solutions as part of their water use licensing conditions. These PPPs would include the national Department Water and Sanitation (DWS), Sedibeng district municipality, Eskom, ArcelorMittal and Rand Water the bulk water utility in the study area. An in depth study of water reuse public perception, cost of water reuse, establishing purpose specific reuse guidelines and water quality monitoring and management plan for study area is recommended before implementation. Monitoring, which is one of the barriers in risk abatement, should include for the study area emerging pathogens, inorganic and organic contaminants of concern such as endocrine disrupting chemicals (EDCs). / Dissertation (MSc)--University of Pretoria, 2016. / Centre for Wildlife Management / Unrestricted

No description available.

I analyzed lake fertilization (with nitrogen and phosphorus) as a tool to assist in the recovery of the Snake River sockeye salmon (Oncorhynchus ~) in the oligotrophic Sawtooth Valley Lakes in southcentral Idaho. These analyses involved monitoring, manipulating, and modelling several aspects of the lakes' primary producer, nutrient, and light parameters. In Pettit Lake, I evaluated the effects of metalimnetic and epilimnetic fertilization in 330-m 3 mesocosms. The metalimnetic treatment was equal to or more effective than the epilimnetic treatment in increasing chlorophyll a, phytoplankton biovolume, and primary productivity, yet caused smaller changes in periphyton growth and water clarity. Thus, metalirnnetic fertilization may provide a tool for increasing lake productivity while minimally impacting water clarity. The Sawtooth Valley Lakes had deep chlorophyll maxima (DCM) with mean chlorophyll a peaks 240-1000% of mean epilimnetic concentrations. The DCM existed at low light levels and accounted for 36- 72% of the lakes' primary production. Epilimnetic fertilization of330-m 3 mesocosms in Redfish Lake increased levels of primary productivity and chlorophyll a, but decreased Secchi depths and light available in the meta- and hypolimnion. I modelled the effects of increased chlorophyll (resulting from epilimnetic fertilization) and decreased light penetration on vertical primary productivity profiles. The simulations showed a large increase in epilimnetic primary productivity due to fertilization, and only a slight decrease in production in the deeper strata due to self-shading. I also modelled the dependence of Red fish Lake's production on nutrients from the watershed, from lake fertilization, and from marine-derived nutrients from salmon. The model utilized our water budget and nutrient loading measurements. The model and empirical evidence indicated that even before hydropower dams were present in the migration corridor, marine-derived nutrients were not of major importance to lake production, contributing only ~3% of the lake's annual phosphorus load. This contribution was partially offset by the lake's quick flushing rate (3 yr) and phosphorus export by smolts. The model predicted annual adult salmon returns to be 3,800 under pre-dam conditions, 370 under modern conditions, 750 when doubling watershed nutrient loading (simulating lake fertilization), and 780 when doubling migration survival.

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No description available.

Fecal contamination in estuaries has become an increasing concern worldwide. The use of wetlands for wastewater treatment has expanded due to their natural ability to improve water quality by removing suspended sediments, nutrients, and fecal bacteria. In general, most of the removal occurs through deposition and accumulation in the wetland substrate. This would suggest that wetlands are effective filters for fecal coliform transported from terrestrial environments to surface waters. It has also been hypothesized, however, that wetlands may be an intermittent source of fecal coliform in tidal systems as a result of wildlife deposition and /or accumulation from terrestrial sources. To investigate the role of tidal wetlands in fecal coliform loadings from small estuarine systems, this project examines the difference between monitoring data and modeling data for shellfish growing areas in Virginia. Results suggest that models should treat tidal wetlands as discrete components of contributing watersheds, rather than assuming they can be grouped with forested land areas. Tidal wetlands’ role in fecal coliform transport could be embodied through the net sediment transport between tidal wetland and adjacent coastal water. When the tidal wetland substrate is resuspended, what happens to the water quality? Do tidal wetlands contribute to and how they contribute to the high amount of fecal coliform (FC) in shellfish harvesting zone? To address these questions, Loading Simulation Program C++ (LSPC) and a hydrodynamic model - Tidal Prism Water Quality Model were used to simulate fecal coliform transport through the watershed (including wetlands) and coastal waters with the support of the project of Development of Shellfish TMDLs for Virginia. The error analysis, that is the discrepancy between the model prediction and observation data, will then be used to explore the sinks and/or sources of fecal pollution in tidal marshes. Seasonal variation of fecal coliform concentrations in shellfish growing water and model sensitivity tests will be analyzed and discussed surrounding this issue.

No description available.