Study of wastewater treatment ponds at full-scale compared the areal total ammonia nitrogen (TAN) removal rates and specific TAN removal rates of high-rate algal ponds (HRPs) to the TAN removal rates of facultative ponds. The outer high-rate algal pond (HRPO) demonstrated superior specific and areal TAN removal rates compared to the inner HRP and the two facultative ponds. Solids return into the HRPO for a portion of the study period yielded increased volatile suspended solids content but no noticeable increase in TAN removal rate. Nitrification modeling for the HRPO tested multilinear regression, multilinear regression on every second observation of the data set, and a nonlinear Michaelis-Menten regression. The multilinear regression on the full data set explained the most variance with an R2 = 55.9% and the following significant (p-value < 0.05) variables: solar insolation, temperature, and ambient TAN concentration. Wastewater treatment pond systems are used worldwide as a method for affordable solids and nutrient removal, but these systems can be less predictable due to their reliance on biological processes. This thesis project recorded various water quality parameters and nitrogen species concentrations on a weekly basis from July 2020 to April 2022 to compare pond performance and identify process improvements. Accurately modeling a pond’s performance will better allow operators to save on aeration and coagulation costs while still meeting effluent goals.

I surveyed macroinvertebrate assemblages in ponds in three grazing regimes (ungrazed, rotationally grazed, and continuously grazed) in spring and summer of 2019 on the Osage Plains ecoregion of Missouri. Total suspended solids, turbidity, and organophosphates were lower in ungrazed ponds than in both grazed treatments, and water transparency and aquatic macrophyte cover was significantly higher. Richness was positively correlated with average depth, deepest depth, and water transparency and negatively correlated with turbidity and organophosphate levels. Overall, ungrazed ponds supported higher taxa richness and diversity across all taxa, as well as higher Diptera: Chironomidae, Odonata, and Trichoptera richness. Ungrazed ponds contained 29 unique genera and three unique families compared to two unique genera and two families in rotationally grazed ponds, and one 6 unique genera and one family in continuously grazed units. PerMANOVA results confirmed differences in habitat variables between ungrazed treatments and both grazed treatments; PCA analysis indicated that decreased taxa abundances were mostly associated with nitrate, bank slope, temperature, and pH and, while transparency and vegetation (emergent and cattails) were associated with increased abundances. PerMANOVA results confirmed seasonal differences in ungrazed ponds and continuously grazed treatments for total taxa and families. Chironomid communities differed between treatments and between seasons for ungrazed ponds and both grazing treatments. Fish presence reduced abundance of total taxa across seasons and in spring and Chironomidae taxa across seasons.

Thesis (S.M.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2006. / Includes bibliographical references (p. 64-68). / Salt pond is a meromictic system with an outlet to the sea allowing denser seawater to occupy the monimolimnion while the mixolimnion has relatively low salinity and is the site of greater mixing and microbial activity. The density contrast between the two layers allows for a unique geochemical environment characterized by steep redox gradients at the interface. This chemocline is a habitat for magnetotactic bacteria (MB), and the spatial and temporal distribution of MB in the system along with geochemical (Fe2+, H2S, pH, 02 (aq), etc.) profiles have been analyzed from 2002 - 2005. It has been previously observed that magnetite-producing cocci occupy the top of the chemocline and greigite-producing MB occur at the base of the chemocline and in the sulfidic hypolimnion. This distribution may be attributed to analyte profiles within the pond; depth profiles show a sudden drop of dissolved oxygen (DO) at the chemocline associated with an increase in dissolved Fe (II) concentrations that peak where both 02 and H2S are low. In the sulfidic hypolimnion, Fe (II) concentrations decrease, suggesting buffering of Fe(II) by sulfide phases. / (cont.) Maximum concentrations of iron (II) and sulfide are 3 1 gM and 3 mM, respectively. Stability diagrams of magnetite and greigite within EH/pH space and measured voltammetric data verify fields of incomplete oxidation resulting in the production of elemental sulfur, thiosulfate and polysulfides. Calculations of the Gibbs free energy in the Salt Pond chemocline for potential microbial redox reaction involving iron and sulfur species indicate abundent potential energy available for metabolic growth. Oxidation of ferrous iron to ferrihydrite in the upper region of the chemocline consistantly has a yield of over -250 kJ/mol 02 (aq), - 12.5 times the proposed 20 kJ/mol minimum proposed by Schink (1997) necessary to sustain metabolic growth. This translates into biomass yields of ~ 0.056 mg dry mass per liter of upper chemocline water. If these numbers are applied to the dominant bacteria of the chemocline (MB that are 3% dry weight iron) then there could be up to ~ 1.68 mg of iron per liter of upper chemocline water just in the MB. / (cont.) This iron can be permanently sequestered by MB into the sediments after death because the organelles containing the iron phases are resistant to degredation. Geochemical and microbial processes relating to the cycling of iron heavily impact this system and perhaps others containing a chemocline that divides the water column into oxic and anoxic zones. / by Peter A. Canovas, III. / S.M.

A new continuous one-dimensional sedimentation model incorporating a new continuous flocculation model that considers aggregation and fragmentation processes was derived and tested. Additionally, a new procedure to model sediment particle size distribution (PSD) was derived. Basic to this development were three different parametric models: Jaky, Fredlund and the Gamma probability distribution (GPD) were chosen to fit three different glass micro-spheres PSDs having average particle sizes of 7, 25 and 35 microns. The GPD provided the best fit with the least parameters. The bimodal GPD was used to fit ten sediment samples with excellent results (< 5% average error). A continuous flocculation model was derived using the method of moments for solving the continuous Smoluchowski coagulation equation with fragmentation. The initial sediment PSD was modeled using a bimodal GPD. This new flocculation model resulted in a new general moments’ equation that considers aggregation and fragmentation processes, which is represented by a system of ordinary differential equations. The model was calibrated using a genetic algorithm with initial and flocculated PSDs of four sediment samples and four anionic polyacrylamides flocculants. The results show excellent correlation between predicted and observed values (R2 > 0.9878). A new continuous one-dimensional sedimentation model that resulted in a scalar hyperbolic conservation law was derived from the well-known Kynch kinematic sedimentation model. The model was calibrated using column tests results with glass micro-spheres particles. Two different glass microspheres particle size distributions (PSDs) were used with average diameters of 7 and 37 microns. Excellent values of coefficient of determination (R2 > 0.89, except for one test replicate) were obtained for both the small and large glass micro-spheres PSDs. These results suggest that the proposed sedimentation model can be expanded to model the sedimentation process inside a sediment pond.

<p>Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.</p><p>This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined. The flow pattern was then simulated in four different storm water ponds, of varying shape and size, by using a physically based computer model. The residence time distribution for each pond could then be calculated as well as the hydraulic efficiency, which is a measure on how well the inflowing water is spread throughout a pond. Finally a multiple regression analysis was performed. This analysis examined how the reduction of lead, copper, zinc and cadmium depends on the following factors: the specific pond area, the variance of the residence time distribution, the hydraulic efficiency and the concentration of incoming metals and suspended solids. The specific pond area is a factor which is defined as the pond area divided by the reduced run off area.</p><p>The results from the multiple regression analysis indicate that an increasing content of inflowing suspended solids leads to a better treatment efficiency regarding lead and copper. The specific area showed to have some effect on the treatment efficiency, but this effect was less than that of the content of inflowing suspended solids. The reduction of cadmium depended mainly on the specific area and the incoming concentration of cadmium. An increasing reduction of zinc could to some extent be explained by an increasing specific area.</p><p>The results from this analysis and earlier studies are emphasizing the fact that adsorption to particles and sediment is one of the main processes for a good separation of heavy metals from storm water. Longer measurements series from additional treatment facilities are needed to build a statistical model which, in the future, can be used to predict the treatment efficiency of storm water ponds.</p> / <p>Dagvatten är regn- och smältvatten som samlas upp i avloppssystem. Då detta vatten huvudsakligen härstammar från urban bebyggelse så kan det innehålla höga halter tungmetaller, närsalter och olja med mera. Idag behandlas förorenat dagvatten bland annat genom nyttjande av dammar, våtmarker och översilningsytor. Dessa behandlingsalternativ har dock visat sig ge varierande resultat med avseende på dess reningseffektivitet.</p><p>Detta arbete har utförts på uppdrag av konsultföretaget SWECO VIAK och syftade till att studera vilka parametrar som påverkar reningseffekten av närsalter och tungmetaller i dagvattendammar. Genom litteraturstudier undersöktes de dominerande reningsprocesserna i dammar och våtmarker. Därefter modellerades strömningen i 4 dammar med varierande form och storlek. Vid detta arbete erhölls en fördelning av uppehållstiden hos vattnet för respektive damm samt ett värde på den hydrauliska effektiviteten, vilken är ett mått på hur väl det inströmmande vattnet sprids ut i dammen. Slutligen utfördes en multipel regressionsanalys.</p><p>Vid denna analys undersöktes hur reningen av bly, koppar, zink och kadmium beror av den specifika dammarean, variansen hos vattnets uppehållstidsfördelning, den hydrauliska effektiviteten samt inkommande metall- och TSS-koncentration (suspenderat material). Den specifika dammarean är en faktor vilken defineras som kvoten mellan dammens area och dess reducerade avrinningsområde.</p><p>Resultaten från den multipla regressionen tyder på att en ökad inkommande halt av suspenderat material till dammen har störst betydelse för en förbättrad avskiljning av bly och koppar. Även den specifika arean och metallkoncentrationen i inflödet visade sig ha en viss, men något mindre, betydelse. Reduktionen av kadmium berodde däremot till störst del av den specifika arean och inkommande kadmiumkoncentration. En ökad reduktion av zink förklarades till viss del av en ökad specifik area. Resultatet att halten av suspenderat material i hög grad avgör reningen samt tidigare studier understryker det faktum att adsorption till partiklar och sediment verkar vara en av de viktigaste processerna för en god avskiljning av tungmetaller. Längre mätserier från fler dagvattendammar krävs dock för att i framtiden ta fram en statistisk modell vilken skulle kunna användas till att prediktera reningseffekten.</p>

Syfte: I dagens läge byggs nya dagvattendammar för att magasinera dagvatten som överbelastar dagvattenledningssystemen och de befintliga dagvattendammarna förblir utan översyn. Eftersom klimatförändringar bidrar till att femårsregn kommer i en högre frekvens ökar flödet av dagvatten och orsakar att allt fler dagvattendammar kommer att bli underdimensionerade. För att bevara samhällsfunktioner utreds en generell arbetsprocess hur kommuner kan undersöka och bevara befintliga dagvattendammar. Metod: Metoderna som används är intervju, fallstudie och litteraturstudie. Intervju bidrar till att lösningar och förslag av undersökningsmetoder och åtgärdsförslag samlas in. Fallstudien utfördes på tre olika dagvattendammar och undersöker vilka undersökningsmetoder som kan användas. Att samla empiri i ett praktiskt fall bör bidra till att utredningens trovärdighet förstärks. De metoderna som användes i fallstudien är beräkningar, sedimentprovtagning och dokumentanalys från underlag av befintliga dagvattendammar. Med hjälp av litteraturstudie analyseras utredningens empiri med andra källor för att kontrollera empirins tillförlitlighet. Resultat: Ett flertal undersökningsmetoder och åtgärdsförslag analyserades. Tre undersökningsmetoder som passade en generell arbetsprocess var: flödesproportionell provtagning, sedimentprovtagning och dagvattenberäkningar med dagvattenmodellen Stormtac. Åtgärdsförslag som passade var: byggnation av en vall runt dammen för att utöka magasineringen, plantering av växter som tar upp näringsämnen och tungmetaller bundna i dagvattnet, utnyttja dagvattendammens form där dagvattendammens hydrauliska effektivitet utnyttjas maximalt samt anlägga fördamm med en makadamvall med vattenlevande växter. Konsekvenser: Flödesproportionell provtagning var tillförlitlig undersökningsmetod enligt intervju och litteraturstudie. Sedimentprovtagning av sediment i botten av inoch utlopp går att nyttjas i en generell arbetsprocess, men vissa föroreningshalter kan vara missvisande beroende på hur detaljerat sedimentprovtagningen görs. Dagvattenmodellen Stormtac och dess beräkningar kan nyttjas i en generell arbetsprocess eftersom Svenskt Vatten P110 (2016) bekräftar modellens beräkningar. Åtgärdsförslagen testades inte i verkliga fall, men effekten bekräftades i intervjun och litteraturstudien. Ett förslag på generell arbetsprocess kunde sammanställas. Stickprovstagning passar sämre in i en generell arbetsprocess. Begränsningar: Fallstudien har begränsats genom att utreda två metoder, varav den ena är dagvattenmodellen Stormtac och den andra är sedimentprovtagning. Utvalda föroreningar som tungmetaller, olja, kväve och fosfor analyseras. Studien avgränsas från att analysera hur recipienter påverkas av de befintliga dagvattendammar som studerats. / Purpose: At present are new stormwater ponds constructed to store stormwater which overloads stormwater pipe systems while existing stormwater ponds remains without overhaul. Since climate changes contributes to five-year rain in a higher frequency, which increases the flow of stormwater and causing more stormwater ponds to be undersized. In order to preserve social functions, are a general work process investigated of how municipalities can investigate and preserve their existing stormwater ponds. Method: The methods that are used are interviews, case study and literature study. The interviews contribute to solutions and proposals of investigation methods and proposals for action. The case study were performed in three stormwater ponds and examines the investigation methods that can be used. Collecting empirical data in a practical case, should increase the investigation’s credibility. The methods used in the case study are calculations, sediment sampling and document analysis of the basis of existing stormwater. Using literature study are the empirical data of the investigation analyzed with other sources to check the reliability of the empirical data. Findings: Several methods of investigations and action proposals were analyzed. Three investigation methods which fit a general work process were: flow proportional sampling, sediment sampling and stormwater calculations through the stormwater model Stormtac. The proposals for action which suited a general work process were: construction of a trench around the pond to expand the storage area, planting plants that take up nutrients and heavy metals tied up in stormwater, exploit the stormwater ponds shape where the hydraulic efficiency are exploited flat out by placing the inlet and outlet on opposite ends, and building trenches with a gravel embankment with aquatic plants. Implications: Flow proportional sampling were a reliable investigation method according to interview and literature study. Sediment sampling of sediment in bottom of in- and outlet can be used in a general work process, but certain contamination levels can be misleading depending on how detailed sediment samplings are done. Stormwater model Stormtac and its calculations can be used in a general workprocess because publication Svenskt Vatten P110 (2016) are confirming the models calculations. The proposals for action were not tested in real cases, but the effect was confirmed in the interview and literature study. Limitations: The case study was limited by investigating two methods, one of which is stormwater model Stormtac and sediment sampling. Selected contaminants such as heavy metals, oil, nitrogen and phosphorus are analysed. The study is delimitated by analyzing how recipients are affected by the studied existing stormwater ponds.

With the world’s population set to reach 9 billion by the mid 21st century food security has never been more important. Increased competition regarding land for agricultural use and over fished seas means it falls to aquaculture to meet the global demands for protein requirements. The largest supply of aquaculture products are cultivated in South East Asia where the industry has seen rapid expansion, particularly of pond production in the past 50 years. This initial expansion has come at a cost with mangrove losses and eutrophication of natural water sources resulting. The impact of these not only affects other stakeholders, including domestic users, but effects will be felt by the aquaculture industry. Indiscriminate release of effluents to the surrounding water reduces the water quality for other users and may impact on the farm discharging the water originally. Poor water quality can then result in poor growth rates and increased mortalities reducing the profitability of the farm and endangering the livelihood of the farmer. If aquaculture is to meet the global food demand it is important that current and future enterprises are developed with sustainability at the fore front. This study investigates the nutrient dynamics in pond culture in South East Asia, focussing initially on four countries outlined by the SEAT (Sustainable Ethical Aquaculture Trade) project, including Thailand, Vietnam, China and Bangladesh. Within the four countries the main species cultured for export were identified resulting in tilapia, shrimp, pangasiid catfish and prawn. Following a farmer survey designed to collect a large volume of data over a range of topics including, water management, social, economic and ethical perceptions, dynamic models were developed, using Powersim Studio 8© (Powersim, Norway), for a generic fish and shrimp ponds separately. The models draw on data from the survey combined with other literature sources to provide outputs for Total Nitrogen and Total Phosphorus in water and sediment as well as dissolved oxygen in the pond water. One of the biggest challenges facing this study was the objective selection of relevant sites for case studies to apply the models to. With such a large preselected set of sites (200 per species per country) it was important that the method be capable of handling such large datasets. Thusly it was decided that a multivariate method be used due to the removal of any pre judgement of the data relevant to the study. In order to investigate the nutrient dynamics water management data was used in the multivariate analysis to identify any similarity between the practices occurring on farms. The case studies in this project focus on Thailand and Vietnam, covering tilapia, shrimp and pangasius. Prawn farms were disregarded as, through the survey, it was discovered most production was for domestic trade. The models were adapted to each farm case study expanding the boundary from pond level to farm level, providing an output for each pond in terms of nutrients in the water and production levels and the farm as a whole for dissolved oxygen and sediment accumulation. The results of the models suggest the culture species to be taking up much of the TN added followed by the accumulation in sediments in shrimp ponds, while TP is mostly taken up by sediments. The fish case studies suggest that most of the TN is discharged to the environment followed by uptake. While Total phosphorus shows similar results to shrimp, accumulating in the sediment. The models presented in this study can be used to estimate outputs from farms of similar water management strategies and can assist in the determination of where improvements can be made to reduce the potential for eutrophication of natural water sources.

O estudo sobre a comunidade microbiana de um sistema de tratamento biológico de águas residuárias é de particular interesse, uma vez que o conhecimento da microbiologia do processo pode levar ao aperfeiçoamento de projetos e ao aumento da eficiência dos sistemas. Este trabalho avaliou a atividade microbiana, particularmente a metanogênica, na lagoa de estabilização anaeróbia da estação de tratamento de esgotos sanitários do município de Cajati - SP. Para isso adotou a taxonomia polifásica na caracterização dos microrganismos e de seus aspectos funcionais, buscando o conhecimento da diversidade dos microrganismos e suas relações nesse tipo de sistema anaeróbio. Objetivou também contribuir para o estabelecimento de um protocolo seguro na realização dos ensaios de atividade metanogênica específica (AME). Os estudos foram realizados com amostras dos sedimento da lagoa coletadas em três períodos diferentes, a saber: outubro/2003, outubro/2004 e dezembro/2004. Durante as amostragens foram determinadas variáveis abióticas como temperatura, condutividade, pH, potencial de óxido-redução e teor de oxigênio dissolvido. Medidas do conteúdo de sólidos totais e voláteis (SV) foram também realizadas. A avaliação da atividade microbiana foi feita por exames microscópicos de contraste de fase e fluorescência, AME, determinação do DNAtotal, FISH - hibridização in-situ com sondas fluorescentes e DGGE - eletroforese em gel com gradiente linear de agentes desnaturantes. Também procedeu-se a contagem de protozoários e análise da presença de algas e cianobactérias. Os resultados revelaram que ocorreu variação nas condições do processo biológico nos períodos amostrados, sendo que em outubro/2004, durante período de fortes chuvas e ventos, a eficiência na redução da DBO foi apenas 18,2%. Nesse período, constatou-se organismos como algas do gênero Chorella sp e cianobactérias do gênero Merismopedia sp. Nas demais coletas a remoção da matéria orgânica medida em DBO foi superior a 80%, com boa atividade anaeróbia. Os resultados mostraram que a relação So/Xo de 0,25 gDQO/g SV foi a mais adequada para determinar o valor de AME, e os ensaios com as amostras de outubro/2003 e dezembro/2004 revelaram valores de AME na faixa de 0,85 a 0,21 mg\'CH IND.4\'/gSV.d. Constatou-se a ocorrência de alterações na estrutura da comunidade microbiana inicial em relação à final do experimento de AME, por meio do DGGE. Verifcou-se também nesses ensaios, que o conteúdo de SV inicial variou entre amostras e substratos, conferindo alta variabilidade ao teste. Os perfís de DGGE das amostras coletadas revelaram variação na estrutura das comunidades microbianas no sedimento, e maior diversidade de bactérias e arquéias quando a lagoa anaeróbia apresentava boa eficiência na redução da DBO. A técnica FISH como adotada não foi eficaz para quantificar e identificar os microrganismos devido ao excesso de hibridizações inespecíficas. Mesmo com suas limitações, a técnica FISH revelou a presença de microrganismos dos Domínios Bacteria e Archaea. Nesse caso, a Família Methanobacteriaceae, a ordem Methanomicrobiales e o gênero Methanosaeta sp. foram confirmados. Nas diferentes coletas, foram identificados protozoários dos gêneros Paramecium sp. e Vorticella sp., e rotíferos dos gêneros Brachionus sp., Trichocerca sp., Synchaeta sp. e Keratella sp. / Microbial diversity studies have remarkable relevance since the knowledge about the microbiology of process can improve plants and system efficiency. This work assessed microbial activity, specially methanogenic, at anaerobic pond for domestic wastewater treatment in the city of Cajati, São Paulo State, Brazil. Poliphasic taxonomy was adopted in onder to contribute to the understanding of microbial community diversity and functionality. As well as to contribute for the establishment of a protocol to the specific methanogenic activity test (SMA). Three periods of sampling were done at the sediment of the anaerobic pond (october 2003, october 2004 and december 2004). Abiotic variables as temperature, conductivity, pH, dissolved oxygen and redox potential were measured at sampling time. TS and VS contents were determined in the samples. Microbial studies were done by observation on optical and fluorescent microscopy, analyse of SMA, totalDNA quantitation, counting of protozoa, analyze of algal and cyanobacteria presence, as well as application of two molecular techniques: Fluorescent in-situ Hybridization (FISH) and Denaturing Gradient Gel Electrophoresis (DGGE). Results showed that general conditions of the anaerobic pond changed among samplings. On October 2004, when the rain and wind were very strong, the organic matter removal efficiency (BOD basis) in the anaerobic pond was low (18.2%) and predominant microorganisms were of aerobic algae, as Chorella sp, and the blue-green algae Merismopedia sp. On the other hand, the removal of organics at other two samplings was more than 80% and the anaerobic microbial activity was verified in the sample. SMA tests showed the food/microorganism rate (F/M) of 0.25 gDQO/g VS was the most suitable to the samples. The results showed SMA values between 0.85 and 0.21 mg\'CH IND.4\'/gVS.d for samples of October 2003 and October 2004. SMA test induced modifications in the structure of the microbial community according to DGGE-profile. In addition, VS content, which was used in the SMA tests as biomass measurement, displayed variable behavior making test results difficult to interpret in some situations. DGGE-profile showed variation in the sediment community structure. Higher bacterial and archaeal diversity was observed when anaerobic pond showed 80%, or more, of DBO removal. FISH technique was not a suitable method to secure quantification and identification of the microorganisms from in excess. In spite of the technique limitations, it was possible to identify microorganisms of Bacteria Domain, Archaea Domain, Methanobacteriaceae Family, Methanomicrobiales Order, and microorganisms belonging to Methanosaeta genus. Paramecium and Vorticella were the protozoans identified in all samplings. Rotifers belonging to genders Brachionus, Trichocerca, Synchaeta and Keratella were also observed.

Made available in DSpace on 2017-07-20T13:41:57Z (GMT). No. of bitstreams: 1 Luiz Fernando Wagner.pdf: 2111456 bytes, checksum: e1870a4be2fbc8c765b6f4d6b0077dbe (MD5) Previous issue date: 2015-03-23 / The disposal of wastes generated in water treatment plants (WTP) by launching into water streams is considered an environmental crime by current Brazilian law and became one of the challenges of drinking water public companies, nowadays. The objective of this study was to analyze the alternative disposal of decanter’s sludge from a WTP, with microsand ballasted sedimentation (ActifloÒ), in a wastewater treatment plant (WWTP) containing upflow anaerobic sludge blanket reactors (UASB) and polishing pond, called WWTP Verde, in the city of Ponta Grossa - PR, through the sewage collection network. The treatment evaluation on the WWTP was performed for seven distinct phases. The phase 1 occurred with WWTP receiving only sewage. Phases 2 to 7 occurred with release of WTP sludge in continuous periods ranging from 4 hours per day (phase 2) to 24 hours per day (phase 7),reaching the percentage of 3.2% of WTP sludge, in relation to the total volume tributary to WWTP. The WWTP operated in stable condition throughout the period,with an average flow tributary of 213.14 L/s. The UASBs operated with HRT in 9.9 hours, VHL in 2.4 m3/m3/d, and OLR ranging from 0.75 to 1.66 kgCOD/m3/d. The polishing pond operated with HRT in 4.5 days and OLR ranging from 765 to 2872 kgCOD/ha/d, which corresponds from 19 to 72 gCOD/m3/d. The removal efficiency of COD and TSS by UASBs and the pond was maintained even with the release of WTP sludge. The overall efficiency of the WWTP ranged between 80% and 86% for COD removal and between 92% and 96% for the TSS removal. It was observed greater removal of nitrogen and phosphorus by UASBs and higher concentration ofnitrogen, phosphorus, potassium and magnesium in the UASB's sludge, in the period in which the WWTP was operated with the WTS sludge release. It was concluded that the sludge release in the sewage collection network is a viable alternative to disposal of the decanter's waste of WTP Actiflo®, not precluding the treatment of sewage in WWTP Verde and the use of sewage sludge in agriculture. However, can be necessary increase the UASB's sludge extraction frequency, from 16 hours of continuous duration of WTP sludge release in the sewage collection network. / A disposição dos resíduos gerados nas estações de tratamento de água (ETA) através do lançamento in natura em corpos d’água é considerada crime ambiental pela legislação brasileira vigente e passou a ser um dos desafios das companhias de abastecimento público de água, na atualidade. O objetivo deste trabalho foi analisar a alternativa de disposição do lodo do decantador de uma ETA, com sedimentação lastreada por microareia (ActifloÒ), em uma estação de tratamento de esgotos (ETE) composta de reatores anaeróbios de leito fluidizado (RALFs) e lagoa de polimento, denominada ETE Verde, no município de Ponta Grossa – PR, através da rede coletora de esgotos. A avaliação do tratamento da ETE foi feita durante sete fases distintas. A fase 1 ocorreu com a ETE recebendo apenas esgoto sanitário. As fases 2 a 7 ocorreram com lançamentos de lodo de ETA, em períodos contínuos que variaram desde 4 horas por dia (fase 2) até 24 horas por dia (fase 7), chegando ao percentual de 3,2% de lodo de ETA, em relação ao volume total afluente à ETE. A ETE operou em condição estável durante todo o período, com uma vazão média afluente de 213,14 L/s. Os RALFs operaram com TDH de 9,9 horas, CHV de 2,4 m3/m3/d e COV aplicada variando entre 0,75 e 1,66 kgDQO/m3/d. A lagoa operou com TDH de 4,5 dias, com TAS variando entre 765 e 2872 kgDQO/ha/d e COV aplicada variando entre 19 e 72 gDQO/m3/d. A eficiência na remoção de DQO e SST pelos RALFs e pela lagoa foi mantida, mesmo com o lançamento do lodo da ETA. A eficiência global da ETE variou entre 80% e 86% para a remoção de DQO e entre 92% e 96% para a remoção de SST. Foi observada maior remoção de nitrogênio e fósforo pelos RALFs e maior concentração de nitrogênio, fósforo, potássio e magnésio no lodo dos RALFs, no período em que a ETE operou com o lançamento do lodo de ETA. Concluiu-se que o lançamento do lodo na rede de esgotos é uma alternativa viável de disposição dos rejeitos do decantador da ETA Actiflo®, não inviabilizando o tratamento de esgotos na ETE Verde e o uso do lodo do esgoto na agricultura. Porém, pode ser necessário aumentar a frequência de extração do lodo dos RALFs, a partir de 16 horas diárias de duração contínua de lançamento de lodo de ETA na rede coletora de esgotos.

Urbanization and increase of impervious areas impact stormwater runoff and can pollute receiving waters. Total suspended solids (TSS) are of particular concern as they can act as a transport agent for other pollutants. Moreover, the existence of the first flush phenomenon (FF), whereby the first stage of storm runoff is the most concentrated, can also have profound ecological effects on receiving waters. Understanding the various types of pollutants in watershed stormwater, their correlation with rainfall parameters (precipitation depth and previous dry days) and with TSS, and the existence of FF is crucial to the design of the most suitable structural best management practice (BMP) that can mitigate their harm. Personal Computer Storm Water Management Model (PCSWMM) is a well-known computer model that can simulate urban runoff quantity and quality and model BMPs. The use of PCSWMM to simulate the first flush phenomenon and to evaluate the effectiveness of structural BMPs has not been previously investigated for a large urban watershed with seriously polluted stormwater runoff. This research is concerned with the study of a framework for designing structural best management practices (BMPs) for stormwater management in a large watershed that is based on comprehensive analysis of pollutants of concern, rainfall parameters of influence, and the existence of FF. The framework was examined using the PCSWMM computer model in the St Anthony Park watershed, an urban watershed in St Paul, Minnesota with a large drainage area of 3,418 acres that discharges directly into the Mississippi River via a storm tunnel. A comprehensive study was undertaken to characterize the overall St. Anthony Park watershed stormwater quality trends for the period of record 2005-2013 for heavy metals, nutrients (ammonia and total phosphorus), sediment (TSS), and bacteria (E. coli). Stormwater was found to be highly contaminated as measured by exceedance of the Minnesota Pollution Control Agency (MPCA) water quality standards and as compared to data obtained from the National Stormwater Quality Database (NSQD). None of the examined parameters significantly correlated with precipitation depth. Concentrations of most heavy metals, total phosphorus and TSS positively correlated with previous dry days, and most pollutants correlated positively with TSS, which provided a strong rationale for using TSS as a representative pollutant in PCSWMM and in examining BMP efficiency. Moreover, BMPs that targeted the particulate fraction in stormwater would be the most efficient in reducing stormwater pollution. A PCSWMM model was built based on the existing drainage system of the watershed, which consisted of inlet structures, manholes, pipes and deep manholes that connect the network pipes to a deep drainage tunnel discharging directly into Mississippi River. The model was calibrated and validated using recorded storm and runoff data. FF was numerically investigated by simulating pollutant generation and washoff. Using three different numerical definitions of FF, the existence of FF could be simulated, and was subsequently reduced by simulating extended dry detention ponds in the watershed. Extended dry detention ponds (EDDPs) are basins whose outlets are designed to detain stormwater runoff for a calculated time that allows particles and associated pollutants to settle. Extended dry detention ponds are a potential BMP option that could efficiently control both water quantity (by diverting initial volumes of stormwater, thus addressing FF) and quality (by reducing suspending pollutants, thus addressing TSS and co-contaminants). Moreover, they are the least-expensive stormwater treatment practice on a cost per treated unit area. Two location-based designs were examined. The first was an EDDP at the main outfall (OFmain), while the second was a set of seven smaller EDDPs within the vicinity of deeper manholes of the deep tunnel (distributed EDDPs). Distributed EDDPs were similar to the OFmain EDDP at reducing peak stormwater flow (52-61%) but superior in reducing TSS loads (20-25% for small particles and 43-45% for larger particles based on the particle sedimentation rate removal constant k) and in reducing peak TSS loads (67-75%). These efficiencies were obtained using the dynamic and kinematic wave routing methods, indicating that they could be used interchangeably for this watershed. The steady state routing method produced unrealistic results and was subsequently excluded from FF analysis. Finally, distributed EDDPs were superior to OFmain EDDP at eliminating FF per the stringent fifth definition (Δ > 0.2). This was true for small values of k. However, larger values of k and other FF tests (above the 45º no-flush line and FF coefficient b < 1) showed that BMP implementation overall failed to completely eliminate FF. This suggested that the extended time required by EDDPs to efficiently remove pollutants from stormwater via settling would compromise their ability to completely eliminate FF. In conclusion, a comprehensive framework was applied so as to better design the most efficient BMPs by characterizing the overall St. Anthony Park watershed stormwater pollutants, their correlation with rainfall parameters and with TSS, and the magnitude of FF. A cost-effective, rapid, and accurate method to simulate FF and study the optimal BMP design was thus implemented for a large urban watershed through the PCSWMM model.