As demand for alternative water sources intensifies, increased use of reclaimed water is important to help achieve water sustainability. In addition to treatment, the manner in which reclaimed water is distributed is a key consideration as it governs the water quality at the point of use. In this work, simulated reclaimed water distribution systems (SRWDSs) were operated for more than two years to examine the role of system design, biofiltration, residual disinfectant type (i.e., chlorine, chloramine, no residual) and temperature on important aspects of chemistry and microbial regrowth under laboratory-controlled conditions. Turbidity decreased to 0.78 NTU after biofiltration and chlorinated treatments from 10.0-12.6 NTU for conditions with chloramine and no residuals. SRWDSs were susceptible to sediment accumulation, which occupied 0.83-3.2% of the volume of the first pipe segment (1 day of hydraulic residence time), compared to 0.32-0.45% volume in the corresponding chlorinated SRWDSs. The mass of accumulated sediment positively correlated (R2 = 0.82) with influent turbidity. Contrary to experiences with potable water systems, chlorine was found to be more persistent and better at maintaining biological stability in the SRWDSs than chloramine, especially at the higher temperatures >22°C common to many water scarce regions. The severe nitrification at the warmer temperatures rapidly depleted chloramine residuals, decreased dissolved oxygen, and caused elevated levels of nitrifiers and heterotrophic cell counts. A metagenomic taxonomic survey revealed high levels of gene markers of nitrifiers in the biofilm samples at 22°C for the chloraminated system. Non-metric multidimensional scaling analysis confirmed distinct taxonomic and functional microbial profiles between the chlorine and chloramine SRWDSs. Reflecting on multiyear experiences operating two different SRWDSs reactor designs, including thin tubes (0.32-cm diameter) and pipe reactors (10.2-cm), illustrated strengths and weaknesses of both approaches in recreating key aspects of biochemical changes in reclaimed water distribution systems. It is clear that approaches deemed successful with drinking water distribution systems may not always directly transfer to simulating reclaimed distribution systems, or to proactively managing full-scale reclaimed systems that have long periods of stagnation and where minimally-treated wastewater with high levels of nutrients and turbidity are used. / Doctor of Philosophy / Increasing water scarcity is creating an impetus for creating more sustainable water supplies. Wastewater effluent is increasingly viewed as in important resource that can reduce both water and energy demand. Reclaiming moderately to minimally-treated secondary wastewater effluent for non-potable reuse (NPR) applications; such as agricultural irrigation, landscaping, and toilet flushing, helps reduce demand for higher quality potable water sources. NPR presently accounts for more than 50% of total reuse and is projected to become increasingly important. While NPR is attractive, important knowledge gaps remain in terms of managing water quality and safety as it is transported through distribution pipes to the point of use. A comprehensive literature review revealed that NPR distribution systems are distinct from conventional drinking water distribution systems (DWDSs) and that it is doubtful if our current understanding of DWDSs would directly transfer to NPR systems. Unlike drinking water systems, NPR systems are currently unregulated at the national level and corresponding state-to-state regulations vary widely. The levels of water treatment can vary from simply distributing untreated effluent from wastewater treatment plants to very high-level treatment with membranes that produces water of equal or even higher quality than many existing tap waters. A common treatment train for minimally-treated NPR involves biologically activated carbon (BAC) filtration and the use of disinfectants (e.g., chlorine or chloramine) to control microbial water quality to the point of use. Prior studies from DWDSs have demonstrated water quality degradation in terms of disinfectant loss, bacterial growth, and aesthetic problems, with the settling of trace particulate matter producing sediment within pipe distribution systems. In particular, accumulated sediment can become a hotspot for water quality deterioration. Considering that minimally-treated reclaimed water can have much higher levels of particulate matter and nutrients than drinking water, it was predicted that NPR distribution systems could suffer from faster water quality degradation than corresponding drinking water systems, especially at the warmer temperatures common in water-scarce regions. This work was the first multi-year attempt to examine the effects of disinfectant (i.e. free chlorine, chloramine, no residual), BAC filtration versus no filtration, water age (up to 5-d versus 28-min), and temperature (14°C, 22°C, 30°C) in different types of lab-scale reactors. Two simulated reclaimed water distribution systems (SRWDSs) including 4-in. diameter Pipe SRWDSs versus 1/8-in. diameter Tube SRWDSs, were designed to study key aspects of full-scale NPR systems and were operated for more than two years to study chemical and microbial changes as distributed water traveled through the two systems. The Pipe SRWDSs were designed to assess the impacts on final water quality after long-term operation that allowed sediment to slowly accumulate, whereas the complementary Tube SRWDS design did not allow sediment to accumulate and only held the water for 28 minutes. Water was sampled regularly to track the trends of key water quality parameters, including disinfectant residuals, dissolved oxygen, nitrogen compounds involved in nitrification reactions, and various types of bacteria of interest. Sequencing of the biological genetic materials on selected samples was conducted to understand the types of bacteria present and their functions under the different circumstances. High levels of sediment were found to accumulate near the beginning of the Pipe SRWDSs, which caused loss of oxygen and disinfectants at the bottom of the pipes. Chlorine was more persistent and better at preventing bacteria growth as water traveled through the distribution system. In contrast, a type of bacteria that used ammonia as a nutrient (i.e., nitrifying bacteria) were observed in the pipes with chloramine (i.e., ammonia plus chlorine) as the disinfectant. The nitrifying bacteria caused rapid depletion of chloramine residuals, especially at temperatures above 22°C. At 30°C both chlorine and chloramine were almost immediately consumed in the pipe reactors. Nitrification is known to trigger water quality problems in chloraminated DWDSs, and we expect that chloraminated RWDSs would be even more susceptible to nitrification and associated water quality degradation issues in Compare the Tube SRWDSs to the Pipe SRWDSs, aside from heavy accumulations of sediment in the pipes versus no sediment in the thin tubes, the tubes clogged repeatedly from formation of thick biofoulants in the systems treated with no disinfectant and chloramine, whereas they remained relatively free of biofoulants and clogging in the tubes with chlorine. Even in just 28 minutes, it took water to move from the start to the end of the tube, both chlorine and chloramine were almost completely consumed in the tubes, due to the unrealistically high pipe surface area to the small flow volume inherent to this reactor design. As NPR becomes increasingly common to help achieve water sustainability, it will be important to deploy laboratory simulations, that are capable of testing and revealing key chemical and microbial processes that affect the operation of these systems and water safety at the point of use. The insights from this first long-term effort of simulating RWDSs highlight some unique characteristics and challenges of RWDSs, and reveals key concepts to help guide future research.

Opportunistic pathogens (OPs) are of special concern for immunocompromised populations and are known to grow in both drinking water and reclaimed water (i.e., non-potable recycled water) distribution systems, with aerosol inhalation and other non-ingestion exposures that are not addressed by existing regulatory frameworks. Factors enabling the growth of OPs in water distribution and premise (i.e., building) plumbing systems distributing reclaimed and other water sources systems are poorly understood especially for the emerging OP, Naegleria fowleri (i.e. brain-eating amoeba). Three phases of investigation were carried out to identify factors that facilitate the growth of OPs in main distribution and premise plumbing systems, with particular attention on reclaimed water systems, aging water mains, and private well systems. Phase one examined the role of biological treatment to remove organic carbon and disinfectant type on the occurrence of OPs during distribution of reclaimed water. Laboratory-scale simulated reclaimed water distribution systems were employed to systematically examine the effects of prior granular activated carbon (GAC) biofiltration of the water; chlorine, chloramines, or no disinfectant, and water ages ranging up to 5 days. The second and third phases of research explored the role of nitrification, iron corrosion, and disinfectant on the growth of N. fowleri both in municipal drinking water from a city grappling with aging water infrastructure and untreated private well water. Results from the simulated reclaimed water distribution systems suggested that biologically-active GAC filtration may unintentionally select for specific OPs, contrary to expectations and experiences with oligotrophic conditions in potable water systems. While GAC biofiltration was associated with lower total bacteria and Legionella spp. gene markers, there were no apparent benefits in terms of other OPs analyzed. Similarly, disinfectant treatments successful for controlling OPs in potable water were either ineffective or associated with increased levels of OPs, such as Mycobacterium spp. and Acanthamoeba spp., in the reclaimed water examined. In the potable water study, it was possible to recreate conditions associated with growth of N. fowleri in the aged main distribution system from where the water for the experiment was collected; including corroding iron mains, nitrification, and disinfectant decay. While the effects of nitrification could not be confirmed, there was a clear association of iron corrosion with N. fowleri proliferation. The role of iron was explored further in what, to the author's knowledge, was the first study of N. fowleri in private wells. Analysis of 40 wells found correlations between N. fowleri and stagnant iron levels, further supporting the hypothesis that iron corrosion or iron encourages the growth of N. fowleri, and, because wells are not routinely disinfected, not necessarily as a result of promoting disinfectant decay. As this study took place following a major flooding event, it provided insight not only into how surface water contamination may influence private well water microbial communities, but also added to the understanding that current recommendations for disinfecting private wells are inadequate and standards should be implemented to aid homeowners in the event of flooding. This exploratory research illuminated several factors influencing the OP growth in a range of water systems. Identifying key variables that control growth is crucial to improving the safety of these systems. / MS / Water borne bacteria that effect the immune systems of the sick, known as opportunistic pathogens (OPs), have become a major heath concern. These organisms are known to grow in drinking water and reclaimed water (i.e., non-potable recycled water) distribution systems yet there are no regulations aimed at prevention. There is also limited knowledge on how premise plumbing and water sources effect the growth, population, and risk of infection by OPs, especially for Naegleria fowleri (i.e. brain-eating amoeba). An investigation was carried out in three parts to determine what influences the growth of OPs in water distribution and household plumbing systems, with particular attention to reclaimed water, municipal drinking water, and private well systems. Phase one examined the role of biological treatment to remove organic carbon and disinfectant type on the occurrence of OPs during distribution of reclaimed water. Laboratory-scale simulated reclaimed water distribution systems were used to examine the effects of granular activated carbon (GAC) biofiltration of the water, disinfectants (chlorine, chloramines, or no disinfectant), and water ages ranging zero to five days. The second and third phases of research explored the role of nitrification, iron corrosion, and disinfectant on the growth of N. fowleri both in municipal drinking water from a city with aging water infrastructure and untreated private well water. Results from the simulated reclaimed water distribution systems suggested that biologically-active GAC filtration may allow for the growth of specific OPs. While GAC biofiltration was associated with lower total bacteria and Legionella spp., there were no apparent benefits in reducing the presence of other OPs. Similarly, common disinfectant treatments for preventing OPs in drinking water were either ineffective or increased viii levels of OPs, such as Mycobacterium spp. and Acanthamoeba spp., in the reclaimed water. In the drinking water study, conditions were introduced to grow N. fowleri in aged drinking water distribution systems with the additions of corroding iron, nitrification (using nitrifying bacteria), and disinfectant. While the effects of nitrification could not be confirmed, there was a clear relationship between iron corrosion and N. fowleri growth. The role of iron was explored further in what, to the author’s knowledge, was the first study of N. fowleri in private wells. Forty wells were examined and the relationships between N. fowleri and stagnant iron levels supported the hypothesis that iron corrosion or iron increases the growth of N. fowleri. As this study took place following a major flooding event, it provided data not only into how surface water contamination may influence private well water microbial communities, but also added to the understanding that current recommendations for disinfecting private wells are inadequate and standards should be implemented to aid homeowners in the event of flooding. This exploratory research highlighted several variables that may allow for the growth of OPs in a range of water systems. Identifying key variables that control growth is crucial to improving the safety of these systems.

The Occoquan Reservoir is a public water supply in northern Virginia. The Occoquan Watershed has developed over the years from rural land uses to metropolitan suburbs within easy commuting distance from Washington, DC. Due to this urbanization, the Occoquan Reservoir is especially vulnerable to hypereutrophication, which results in problems such as algal blooms (including cyanobacteria), periodic fish kills, and taste and odor problems. In the 1970's, a new management plan for the Occoquan Reservoir called for the construction of the Upper Occoquan Sewage Authority (UOSA), an advanced wastewater treatment plant that would take extraordinary measures for highly reliable and highly efficient removal of particulates, organics, nutrients, and pathogens. Eliminating most of the water quality problems associated with point source discharges in the watershed, this state-of-the-art treatment is the foundation for the successful indirect surface water reuse system in the Occoquan Reservoir today. A limnological analysis of thirty years of water quality monitoring data from the reservoir and its two primary tributaries shows that the majority of the nutrient and sediment load to the reservoir comes from nonpoint sources, which are closely tied to hydrometeorologic conditions. Reservoir water quality trends are very similar to trends in stream water quality, and the tributary in the most urbanized part of the watershed, Bull Run, has been identified as the main contributor of sediment and nutrients to the reservoir. Despite significant achievements in maintaining the reservoir as a source of high quality drinking water, the reservoir remains a phosphorus-limited eutrophic waterbody. / Master of Science

abstract: In the recent past, Iraq was considered relatively rich considering its water resources compared to its surroundings. Currently, the magnitude of water resource shortages in Iraq represents an important factor in the stability of the country and in protecting sustained economic development. The need for a practical, applicable, and sustainable river basin management for the Tigris and Euphrates Rivers in Iraq is essential. Applicable water resources allocation scenarios are important to minimize the potential future water crises in connection with water quality and quantity. The allocation of the available fresh water resources in addition to reclaimed water to different users in a sustainable manner is of the urgent necessities to maintain good water quantity and quality. In this dissertation, predictive water allocation optimization models were developed which can be used to easily identify good alternatives for water management that can then be discussed, debated, adjusted, and simulated in greater detail. This study provides guidance for decision makers in Iraq for potential future conditions, where water supplies are reduced, and demonstrates how it is feasible to adopt an efficient water allocation strategy with flexibility in providing equitable water resource allocation considering alternative resource. Using reclaimed water will help in reducing the potential negative environmental impacts of treated or/and partially treated wastewater discharges while increasing the potential uses of reclaimed water for agriculture and other applications. Using reclaimed water for irrigation is logical and efficient to enhance the economy of farmers and the environment while providing a diversity of crops, especially since most of Iraq’s built or under construction wastewater treatment plants are located in or adjacent to agricultural lands. Adopting an optimization modelling approach can assist decision makers, ensuring their decisions will benefit the economy by incorporating global experiences to control water allocations in Iraq especially considering diminished water supplies. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2019

Water scarcity is a global concern that impacts many developing countries, forcing people to depend on unclean water sources for domestic, agricultural, and industrial needs. Wastewater is an alternative water source that contains nutrients needed for crop growth. Wastewater reuse for agriculture can cause public health problems because of human exposure to pathogens. Pathogen monitoring is essential to evaluate the compliance of wastewater with established World Health Organization (WHO) and U.S. Environmental Protection Agency (EPA) wastewater reuse guidelines. Indicator organisms are commonly used to detect pathogens in water and wastewater because they are quick and easy to measure, non-pathogenic, and have simple and inexpensive methods of detection. The objective of this research was to develop a modified double agar layer assay method that can be conducted in the field to quantify bacteriophage to assess the quality of wastewater for agricultural reuse. Results from the modified double agar layer assay were used to investigate the potential of somatic coliphage as an indicator organism for assessing the potential presence of enteric viruses in developing world treated wastewater, and to use the criteria of a good indicator organism to compare the potential of two commonly used indicator organisms, somatic coliphage and fecal coliforms, as an indicator of enteric viruses in wastewater. A modified EPA double agar layer method was developed and deployed in a developing world rural community to effectively quantify the concentration of somatic coliphage in a community managed wastewater treatment system composed of a Upflow Anaerobic Sludge Blanket (UASB) reactor followed by two maturation lagoons. The modified method served as a good indicator of enteric viruses in the water. Somatic coliphages were easily detected and quantified in the field setting using a modified double agar layer method. Somatic coliphage was found to be a potential indicator for enteric viruses rather than fecal coliforms because of their similarity in characteristics and resistances to wastewater treatment. The concentration of somatic coliphage was only reduced by 1.05 log units across the two series maturation lagoon system. Previous literature suggested removal would range from 2.1 to 4.6 log units. Influent wastewater (previously treated by an UASB reactor) had a concentration of 4.38 E+06 PFU/ 100 mL (standard deviation = ±3.7E+06, n = 9) and the treated effluent contained 3.90 E+05 PFU/100 mL (standard deviation = ± 4.5E+05, n = 8) of somatic coliphages. Results suggest that somatic coliphage is a good potential indicator for enteric viruses in wastewater but further research needs to be done.

Estudaram-se soluções para o pós-tratamento de efluentes de reatores UASB e de lagoas de estabilização visando à utilização em irrigação de culturas agrícolas. Nesta aplicação, normalmente são desejáveis bons níveis de remoção de sólidos em suspensão e graus elevados de desinfecção, além da conservação dos principais nutrientes. No caso do efluente de reatores UASB em escala real, foram construídas unidades em escala piloto envolvendo sedimentação, filtração e radiação UV. No primeiro experimento, o efluente dos reatores UASB passou por filtro de areia pressurizado em alta taxa e por reator UV de fluxo contínuo. Nesta etapa a concentração de sólidos em suspensão (SST) no efluente dos reatores UASB teve média de 233 mg/L, devido a problemas operacionais, sendo que o filtro apresentou eficiência média de 60% de remoção de sólidos em suspensão. Porém, como o filtrado apresentou absorbância ainda elevada, média de 0,476 cm-¹, a desinfecção UV resultou ineficiente e a contagem de coliformes do efluente final incompatível com o uso agronômico pretendido. No segundo experimento, o efluente dos reatores UASB recebeu tratamento complementar passando por decantador de alta taxa e filtração em leito de manta geotêxtil, seguindo finalmente para a desinfecção UV. A concentração de SST no efluente dos reatores UASB, sanados os problemas operacionais da ETE teve valor médio de 82 mg/L. Com essa concentração afluente relativamente baixa, o decantador lamelar demonstrou-se pouco eficiente e apresentou efluente com SST médio de 67 mg/L. No entanto, foi bastante útil para conter picos de concentração de sólidos no efluente dos reatores UASB, protegendo a etapa posterior de filtração. No efluente do filtro de manta geotêxtil, o SST médio foi de apenas 7 mg/L., ABS (254nm) de 0,245 cm-1 e Turbidez de 11 UNT. A desinfecção do efluente por radiação ultravioleta com dose recebida de 2,44 W.h/m³, resultou satisfatória com média geométrica de 1,12x101 NMP/100mL de E coli. No caso do efluente de sistema de lagoas de estabilização em escala real, aplicou-se pós-tratamento em escala piloto composto de filtro de areia pressurizado de alta taxa seguido de desinfecção por hipoclorito de sódio. A concentração de SST no efluente da lagoa facultativa teve média de 117 mg/L, enquanto que a média no efluente do filtro foi de 87 mg/L. Para concentrações de cloro dosado de 2,9; 6,2 e 11,7 mg/L, as médias geométricas das densidades de E coli no efluente final resultaram 1,13x10² NMP/100mL, 1,01x101 NMP/100mL e valor não detectado pelo método, respectivamente. Concluiu-se que é possível aplicar pós-tratamentos relativamente simples aos efluentes de reatores UASB e de lagoas de estabilização, quando se deseja uso agronômico e as principais condições operacionais destas unidades puderam ser avaliadas. / It was studied the application of a simple and economical post-treatment of effluent from wastewater treatment plant for the purpose of use on irrigation of agricultural crops. The research was conducted in two different wastewater treatment plants, (1) WTP UASB reactors with two application of post-treatment: (1.1) Post treatment with a sand bed filter pressurized at high-rate followed by ultraviolet disinfection. In this step, the concentration of suspended solids (TSS) in the effluent from the UASB reactor was 233 mg/L, the filter had efficiencies of 60% removal of suspended solids in the effluent from the UASB reactor, however, was not an appropriate result for effective disinfection of the effluent in the ultraviolet reactor. Absorbance values reached an average of 0.476 cm-¹. (1.2) Post-treatment at a high rate clarifier and on geotextile bed filtration to apply the ultraviolet disinfection. The concentration of TSS in the UASB reactor effluent has an average value of 82 mg/L, the concentration of the same parameter in the effluent from the clarifier was 67 mg/L and effluent of the filter geotextile, 7 mg/L. The system removed 91% of TSS in the effluent of the UASB reactor. In this experiment there was obtained a post-treated effluent with ABS (254nm) of 0.245 cm-1 and a turbidity of 11 NTU. The disinfection of the effluent by ultraviolet radiation with a dose received of 2.44 W.h/m³, obtained satisfactory results with geometric mean of 1.12x101 NMP/100mL E coli. (2) WTP by stabilization ponds with post-treatment in a pressurized sand filter followed by highrate disinfection by sodium hypochlorite solution. A TSS concentration in the effluent from facultative pond had an averaged 117 mg/L, the concentration of the same parameter in the effluent of the filter was 87 mg/L. With application of 2.88 mgCl2/L resulted in 1.13x10² NMP/100mL E coli, for the application of 6.2 and 11.7 mg/L chlorine was obtained 1.01x101 NMP/100mL E coli and ND, respectively.

Estudaram-se soluções para o pós-tratamento de efluentes de reatores UASB e de lagoas de estabilização visando à utilização em irrigação de culturas agrícolas. Nesta aplicação, normalmente são desejáveis bons níveis de remoção de sólidos em suspensão e graus elevados de desinfecção, além da conservação dos principais nutrientes. No caso do efluente de reatores UASB em escala real, foram construídas unidades em escala piloto envolvendo sedimentação, filtração e radiação UV. No primeiro experimento, o efluente dos reatores UASB passou por filtro de areia pressurizado em alta taxa e por reator UV de fluxo contínuo. Nesta etapa a concentração de sólidos em suspensão (SST) no efluente dos reatores UASB teve média de 233 mg/L, devido a problemas operacionais, sendo que o filtro apresentou eficiência média de 60% de remoção de sólidos em suspensão. Porém, como o filtrado apresentou absorbância ainda elevada, média de 0,476 cm-¹, a desinfecção UV resultou ineficiente e a contagem de coliformes do efluente final incompatível com o uso agronômico pretendido. No segundo experimento, o efluente dos reatores UASB recebeu tratamento complementar passando por decantador de alta taxa e filtração em leito de manta geotêxtil, seguindo finalmente para a desinfecção UV. A concentração de SST no efluente dos reatores UASB, sanados os problemas operacionais da ETE teve valor médio de 82 mg/L. Com essa concentração afluente relativamente baixa, o decantador lamelar demonstrou-se pouco eficiente e apresentou efluente com SST médio de 67 mg/L. No entanto, foi bastante útil para conter picos de concentração de sólidos no efluente dos reatores UASB, protegendo a etapa posterior de filtração. No efluente do filtro de manta geotêxtil, o SST médio foi de apenas 7 mg/L., ABS (254nm) de 0,245 cm-1 e Turbidez de 11 UNT. A desinfecção do efluente por radiação ultravioleta com dose recebida de 2,44 W.h/m³, resultou satisfatória com média geométrica de 1,12x101 NMP/100mL de E coli. No caso do efluente de sistema de lagoas de estabilização em escala real, aplicou-se pós-tratamento em escala piloto composto de filtro de areia pressurizado de alta taxa seguido de desinfecção por hipoclorito de sódio. A concentração de SST no efluente da lagoa facultativa teve média de 117 mg/L, enquanto que a média no efluente do filtro foi de 87 mg/L. Para concentrações de cloro dosado de 2,9; 6,2 e 11,7 mg/L, as médias geométricas das densidades de E coli no efluente final resultaram 1,13x10² NMP/100mL, 1,01x101 NMP/100mL e valor não detectado pelo método, respectivamente. Concluiu-se que é possível aplicar pós-tratamentos relativamente simples aos efluentes de reatores UASB e de lagoas de estabilização, quando se deseja uso agronômico e as principais condições operacionais destas unidades puderam ser avaliadas. / It was studied the application of a simple and economical post-treatment of effluent from wastewater treatment plant for the purpose of use on irrigation of agricultural crops. The research was conducted in two different wastewater treatment plants, (1) WTP UASB reactors with two application of post-treatment: (1.1) Post treatment with a sand bed filter pressurized at high-rate followed by ultraviolet disinfection. In this step, the concentration of suspended solids (TSS) in the effluent from the UASB reactor was 233 mg/L, the filter had efficiencies of 60% removal of suspended solids in the effluent from the UASB reactor, however, was not an appropriate result for effective disinfection of the effluent in the ultraviolet reactor. Absorbance values reached an average of 0.476 cm-¹. (1.2) Post-treatment at a high rate clarifier and on geotextile bed filtration to apply the ultraviolet disinfection. The concentration of TSS in the UASB reactor effluent has an average value of 82 mg/L, the concentration of the same parameter in the effluent from the clarifier was 67 mg/L and effluent of the filter geotextile, 7 mg/L. The system removed 91% of TSS in the effluent of the UASB reactor. In this experiment there was obtained a post-treated effluent with ABS (254nm) of 0.245 cm-1 and a turbidity of 11 NTU. The disinfection of the effluent by ultraviolet radiation with a dose received of 2.44 W.h/m³, obtained satisfactory results with geometric mean of 1.12x101 NMP/100mL E coli. (2) WTP by stabilization ponds with post-treatment in a pressurized sand filter followed by highrate disinfection by sodium hypochlorite solution. A TSS concentration in the effluent from facultative pond had an averaged 117 mg/L, the concentration of the same parameter in the effluent of the filter was 87 mg/L. With application of 2.88 mgCl2/L resulted in 1.13x10² NMP/100mL E coli, for the application of 6.2 and 11.7 mg/L chlorine was obtained 1.01x101 NMP/100mL E coli and ND, respectively.

Devido à escassez de recursos hídricos, efluentes de plantas de tratamento de águas residuárias têm sido reutilizadas ou recicladas em todo o mundo. Em algumas regiões áridas e em particular em regiões semi-áridas, o reuso de água tem sido reconhecido como um valioso recurso. Entretanto, dependendo da natureza do uso, surgem preocupações sobre potenciais riscos associados à presença de patógenos e contaminantes e a saúde humana. Uma grande variedade de contaminantes orgânicos pode estar presente nos esgotos domésticos e ser recirculado pelo ambiente. Alguns desses compostos apresentam o potencial de desregular as funções normais do sistema endócrino dos organismos e assim, causar efeitos adversos sobre a saúde humana. Entre esses compostos, incluem-se os hormônios estrógenos naturais e sintéticos. Nesse trabalho, desenvolvido na Estação Experimental de Tratamento de Águas Residuárias Urbanas do IPH/UFRGS, localizada nas dependências da ETE São João – Navegantes / DMAE / Porto Alegre / RS, foi investigada a ocorrência de hormônios naturais e sintéticos em grãos de milho cultivados por processo de irrigação por sulcos com efluentes domésticos tratados. O método analítico utilizado para quantificação dos hormônios de interesse foi a cromatografia líquida de alto desempenho (HPLC). Os resultados obtidos confirmam a presença de hormônios naturais e sintéticos no esgoto bruto e nos efluentes tratados, mas em concentrações extremamente baixas e não indicam processo de transferência ou acúmulo desses contaminantes para os grãos de milho. / Due to the scarcity of fresh water resources, effluents from wastewater treatment plants have increasingly been reclaimed and reused around the world. In some arid and semiarid regions, in particular, reclaimed water has been recognized as a valuable resource for non-potable use such as irrigating crops. However, depending on the nature of application, there is concern about potential risks associated with pathogens and organic contaminants to the environment and human health. A wide range of organic contaminants may be present in wastewater and the environment receiving it. These include natural and synthetic estrogens have the potential to disrupt the normal function (s) of endocrine systems in organisms and thus causing health effects on wildlife and humans. In the present work, developed at “Estação Experimental de Tratamento de Águas Residuárias Urbanas do IPH/UFRGS”, located on the ETE São João – Navegantes /DMAE / Porto Alegre /RS, was investigated the occurrence of natural and synthetic hormones in corn’s grain (Zea mays) cultivated by furrow irrigation of treated domestic effluents. The analytic method used for the hormones quantification was the High Performance Liquid Chromatography (HPLC). The results confirm the presence of natural and synthetic hormones on the untreated and treated effluents, although with a very low concentration and not indicated accumulation of this one to the corn’s grain.

Devido à escassez de recursos hídricos, efluentes de plantas de tratamento de águas residuárias têm sido reutilizadas ou recicladas em todo o mundo. Em algumas regiões áridas e em particular em regiões semi-áridas, o reuso de água tem sido reconhecido como um valioso recurso. Entretanto, dependendo da natureza do uso, surgem preocupações sobre potenciais riscos associados à presença de patógenos e contaminantes e a saúde humana. Uma grande variedade de contaminantes orgânicos pode estar presente nos esgotos domésticos e ser recirculado pelo ambiente. Alguns desses compostos apresentam o potencial de desregular as funções normais do sistema endócrino dos organismos e assim, causar efeitos adversos sobre a saúde humana. Entre esses compostos, incluem-se os hormônios estrógenos naturais e sintéticos. Nesse trabalho, desenvolvido na Estação Experimental de Tratamento de Águas Residuárias Urbanas do IPH/UFRGS, localizada nas dependências da ETE São João – Navegantes / DMAE / Porto Alegre / RS, foi investigada a ocorrência de hormônios naturais e sintéticos em grãos de milho cultivados por processo de irrigação por sulcos com efluentes domésticos tratados. O método analítico utilizado para quantificação dos hormônios de interesse foi a cromatografia líquida de alto desempenho (HPLC). Os resultados obtidos confirmam a presença de hormônios naturais e sintéticos no esgoto bruto e nos efluentes tratados, mas em concentrações extremamente baixas e não indicam processo de transferência ou acúmulo desses contaminantes para os grãos de milho. / Due to the scarcity of fresh water resources, effluents from wastewater treatment plants have increasingly been reclaimed and reused around the world. In some arid and semiarid regions, in particular, reclaimed water has been recognized as a valuable resource for non-potable use such as irrigating crops. However, depending on the nature of application, there is concern about potential risks associated with pathogens and organic contaminants to the environment and human health. A wide range of organic contaminants may be present in wastewater and the environment receiving it. These include natural and synthetic estrogens have the potential to disrupt the normal function (s) of endocrine systems in organisms and thus causing health effects on wildlife and humans. In the present work, developed at “Estação Experimental de Tratamento de Águas Residuárias Urbanas do IPH/UFRGS”, located on the ETE São João – Navegantes /DMAE / Porto Alegre /RS, was investigated the occurrence of natural and synthetic hormones in corn’s grain (Zea mays) cultivated by furrow irrigation of treated domestic effluents. The analytic method used for the hormones quantification was the High Performance Liquid Chromatography (HPLC). The results confirm the presence of natural and synthetic hormones on the untreated and treated effluents, although with a very low concentration and not indicated accumulation of this one to the corn’s grain.

Devido à escassez de recursos hídricos, efluentes de plantas de tratamento de águas residuárias têm sido reutilizadas ou recicladas em todo o mundo. Em algumas regiões áridas e em particular em regiões semi-áridas, o reuso de água tem sido reconhecido como um valioso recurso. Entretanto, dependendo da natureza do uso, surgem preocupações sobre potenciais riscos associados à presença de patógenos e contaminantes e a saúde humana. Uma grande variedade de contaminantes orgânicos pode estar presente nos esgotos domésticos e ser recirculado pelo ambiente. Alguns desses compostos apresentam o potencial de desregular as funções normais do sistema endócrino dos organismos e assim, causar efeitos adversos sobre a saúde humana. Entre esses compostos, incluem-se os hormônios estrógenos naturais e sintéticos. Nesse trabalho, desenvolvido na Estação Experimental de Tratamento de Águas Residuárias Urbanas do IPH/UFRGS, localizada nas dependências da ETE São João – Navegantes / DMAE / Porto Alegre / RS, foi investigada a ocorrência de hormônios naturais e sintéticos em grãos de milho cultivados por processo de irrigação por sulcos com efluentes domésticos tratados. O método analítico utilizado para quantificação dos hormônios de interesse foi a cromatografia líquida de alto desempenho (HPLC). Os resultados obtidos confirmam a presença de hormônios naturais e sintéticos no esgoto bruto e nos efluentes tratados, mas em concentrações extremamente baixas e não indicam processo de transferência ou acúmulo desses contaminantes para os grãos de milho. / Due to the scarcity of fresh water resources, effluents from wastewater treatment plants have increasingly been reclaimed and reused around the world. In some arid and semiarid regions, in particular, reclaimed water has been recognized as a valuable resource for non-potable use such as irrigating crops. However, depending on the nature of application, there is concern about potential risks associated with pathogens and organic contaminants to the environment and human health. A wide range of organic contaminants may be present in wastewater and the environment receiving it. These include natural and synthetic estrogens have the potential to disrupt the normal function (s) of endocrine systems in organisms and thus causing health effects on wildlife and humans. In the present work, developed at “Estação Experimental de Tratamento de Águas Residuárias Urbanas do IPH/UFRGS”, located on the ETE São João – Navegantes /DMAE / Porto Alegre /RS, was investigated the occurrence of natural and synthetic hormones in corn’s grain (Zea mays) cultivated by furrow irrigation of treated domestic effluents. The analytic method used for the hormones quantification was the High Performance Liquid Chromatography (HPLC). The results confirm the presence of natural and synthetic hormones on the untreated and treated effluents, although with a very low concentration and not indicated accumulation of this one to the corn’s grain.