bluuebunny/crossref_metadata_2025 huggingface dataset:
Fate of Human Enteric Viruses (Rotaviruses and Entero Viruses) in Sewage after Primary Sedimentation
Authors: Bosch A. , Lucena F. , Jofre J.
Published: May 2018

A wastewater treatment plant, which treats sewage by either mechanical primary sedimentation or lime coagulation, was used for modelling the fate of human enteric viruses after these treatments. The occurrence of human rotaviruses and enteroviruses was monitored in sewage influent, effluent and sludge samples. The level of indigenous enteric viruses in raw sewage was very high (up to 10 000 I.U./l); the values for rotavxrus and enterovxrus were of the same magnitude, although no correlation was found between the levels of both kinds of human enteric viruses. Both rotaviruses and enteroviruses were removed from sewage and transferred to sludge at similar rates after mechanical sedimentation, although rotaviruses were more efficiently recovered from sludge samples than enteroviruses. After chemical coagulation by lime treatment, most human enteric viruses in sludge were inactivated. Lime coagulation should be regarded as a most effective single-step treatment for the removal of viral pathogens such as rotaviruses and enteroviruses from sewage.
Ten Year Survey of Salmonella and Enterovirus in Raw and Treated Waters in the Great São Paulo Area, Brazil
Authors: Martins M. T. , Sanchez P. S. , Marques E. , Monteiro C. K. , Molina A. G.
Published: May 2018

The monitoring program for Enterovirus and Salmonella in raw and treated waters, from nine water treatment plants of Great São Paulo, Brazil, has been developed by CETESB- The São Paulo State Environmental Protection Agency under a contract with SABESP - Water Industry and Sewage Works Company, since 1976. For Salmonella analysis a total of 904 samples of raw water and 997 of treated water were analysed during these last 10 years. A percentage of 30.6 of 904 raw water samples revealed the presence of Salmonella. These pathogenic bacteria were absent in treated water. For Enterovirus, 383 samples of raw water were analysed, out of these 14.9% revealed the presence of virus. From a total of 366 viruses isolated 195 (53.3%) were Poliovirus, 79 (21.6%) were Echovirus, 30 (8.2%) were Coxsackievirus and 62 (16.9%) isolates were untyped. As far as treated water is concerned for the 10 year study, only 3 out of 975 samples were positive for viruses (Poliovirus type 2, Coxsackie A16, and one isolate untyped). Coliforms and Salmonella were not detected in these 3 samples. Residual chlorine was present. In the sample where Poliovirus type 2 was present, free residual chlorine was 1.5 mg/L and pH 9.2. This survey demonstrated that the conventional procedures for water treatment used by SABESP were in general efficient for Enterovirus and Salmonella removal.
Two Year Survey of Indicator Bacteria and Enteroviruses during the Preparation of Drinking Water from Three Water Treatment Plants in Paris Suburbs
Authors: Joret J. C. , Dupin T. , Hassen A. , Agbalika F. , Hartemann P.
Published: May 2018

Three conventional drinking water treatment plants were sampled monthly during a two year period for the removal of indicator bacteria and enteroviruses. Most 20 ℓ samples of raw river water were positive for viruses (principally Coxsackievirus B4 and B6, and echoviruses) with average virus concentrations varying from 0-3.5 PFU/ℓ for the less polluted river water (103-104 fecal coliforms/100 mℓ) to 0.1-20 PFU/ℓ for the highly polluted source (104-105 fecal coliforms/100 mℓ). In spite of these high levels of bacterial contamination, no viruses were detected from the 72 samples of 1 000 ℓ finished water. These results are discussed in regard to the virus removal efficiency of each treatment step previously evaluated by both pilot plant and full-scale water treatment plant studies. The mean virus removal was found to be 0-85% for storage (3 day period) of river water, 64-98% for preozonation (0.8 mg/ℓ/2-3 minutes), 31-90% for clarification by coagulation, flocculation and decantation, and 77-99% for sand filtration (5m/h). Total coliform counts were found to be good indicators of treatment for the presence of viruses in postozonated (1.5 mg/ℓ/10 min) water.
Studies of Procedures for Recovery of Viruses from Activated Sludge
Authors: Shimohara Etsuko , Nashida Minoru , Kaneko Mitsumi
Published: May 2018

Several elution media were examined to evaluate their suitability for recovering seeded poliovirus 1 from return activated sludge. Although there were no distinct differences of virus recovery efficiency among the media tested, 3% beef extract solution at pH 9 seemed to be the most practical eluent for the recovery of the viruses adsorbed from the sludge with an average recovery efficiency of 21%, with a range of 6.1 to 34%. The organic flocculation procedure using beef extract was applied to concentrate the eluted viruses. Its effect depended on the type of eluate, and viruses were not always concentrated well.
Marine Outfall Studies in Development Areas of South Africa
Authors: Toms G.
Published: May 2018

A recent policy of decentralizing growth in South Africa has led to the designation of neu coastal development areas. Growth of such areas, stimulated by the attraction of industries should be accompanied by a careful assessment of possible associated marine pollution problems. In particular, the disposal of industrial and/or domestic effluents to sea may initially appear an attractive option to planners and developers. Consequently the investigation of the feasibility of the marine disposal option is an essential component of the planning process. An on-going series of such studies in nominated priority coastal development areas has been undertaken by the National Research Institute for Oceanology since 1980. This paper reviews the progress of these studies and outlines the preliminary engineering and oceanographic investigations. Two case studies, Saldanha and Richards Bay, are reviewed. In the latter case, some interesting design aspects of the recently completed outfall are discussed.
The Association Between Morbidity among Bathers and Microbial Quality of Seawater
Authors: Fattal B. , Peleg-Olevsky E. , Yoshpe-Purer Y. , Shuval H. I.
Published: May 2018

During the summer of 1983, a prospective epidemiological study was carried out at three coastal beaches in the area of Tel-Aviv, Israel, in order to investigate the effect of marine pollution on morbidity among bathers. A total of 615 families comprising 2 231 persons, 23% of them aged 0–4 years, were interviewed for this study. A total of 78 seawater samples were laboratory tested on the day of collection for the concentration of six bacterial indicators: fecal coliforms, fecal streptococci, enterococci, E.coli, Staphylococcusaureus and Pseudomonas aeruginosa. The geometric mean of the fecal coliforms was the highest at all beaches, and the concentration of pseudomonas the lowest. All beaches complied with Israel Ministry of Health, bacterial standards for bathing beaches and were within the WHO/UNEP guidelines for fecal coliforms. However, analysis of the results indicated that symptoms of enteric morbidity among swimmers,particularly in the 0–4 year old age group, were related to “high” density levels of enterococci, E.coli and staphylococci. Also, swimmers had more morbidity symptoms of all types (“enteric”,“respiratory” and “others”) than nonswimmers, regardless of the microbial quality of seawater.
Evaluation of the Efficiency of Santos/São Vicente Preconditioning Station for an Oceanic Submarine Outfall
Authors: Garcia Agudo E. , Amaral R. , Berzin G.
Published: May 2018

The efficiency of solids removal and the resultant effect on submarine outfall performance of the sewage preconditioning station of Santos and Sao Vicente cities are evaluated. Emphasis is given to the removal of floatable materials that could emerge on the water surface. It was found that most floatables are disaggregated in the pumping process, thus changing their floating properties. The efficiency of the removal of floating materials by the milliscreens of size of openings 1.5 mm is about 70%; of the remaining floatables that are pumped to the submarine outfall, only about 50% appear on the water surface. The removal efficiencies for biochemical oxygen demand (BOD), chemical oxygen demand (COD), and suspended and settleable solids are much lower than those seen with milliscreens with smaller openings.
The Effect of Sewage Sludge Disposal to Sea through Pipelines Previously Discharging only Settled Effluent
Authors: McGlashan J. E. , Macleod D. C.
Published: May 2018

The City of Durban has two submarine outfall sewers designed for the disposal of approximately 365 000 m3/d of domestic and industrial effluents. Until recently these outfall sewers were only permitted to discharge settled effluents, the resultant sludge having to be treated and disposed of on land in the one instance and incinerated in the other. As the result of a two year programme of research the city has been permitted to discharge settled effluent from both outfalls to which the underflow from the sedimentation basins has been reintroduced. Retention of the sedimentation basins has permitted effective removal of floatable material. The pipelines were operated during the research period by discharging only settled effluent from the one whilst from the other the discharge consisted of the settled effluent stream to which the sludge had been reintroduced. Halfway through the programme the roles of the two pipelines were reversed. This paper briefly reviews marine disposal in South Africa, the Durban submarine outfalls, the events which preceded the research project, the design of the research programme and the results of the study in terms of bacteriological, biological and chemical monitoring, current measurements in the immediate vicinity of the pipelines and dilution calculations with the aid of more rigorous mathematical treatment.
The use of Current Data in Ocean Outfall Design
Authors: Roberts Philip J. W.
Published: May 2018

Some of the ways in which current meter data can aid in the design of ocean outfalls are discussed. Examples are given, which include time series analyses of currents obtained in Puget Sound, near Alki Point, the prediction of initial dilution of San Francisco, the prediction of far field dilution and transport in Southern California coastal waters, and prediction of the visitation frequency, or transport probability, off Alki Point.
Key Issues in Planning Submarine Outfalls for Sydney, Australia
Authors: Clancy K. G. , Carroll D. J.
Published: May 2018

This paper describes three large tunnelled submarine ocean outfalls, planned to safely discharge primary effluent from about two-thirds of the regional population of Sydney, Australia into deep ocean water. Environmental and investigation aspects are dealt with briefly. Interesting aspects of design and construction planning are described. The design includes the handling of special hydraulic problems such as dilution and salt water removal. The construction planning foreshadows the extensive use of tunnelling machines including roadheaders and a full face tunnel boring machine. The offshore engineering describes the design and testing of innovative G R P risers and diffusers, and their intended installation by a semi–submersible drill ship using standard oil field techniques. The cost estimate and program is included.
Analytical Quality Control (AQC) For Monitoring Trace Metals in the Coastal and Estuarine Environment
Authors: Gardner M. J. , Hunt D T. E. , Topping G.
Published: May 2018

It is widely recognised that, unless special steps are taken, analytical results from a group of laboratories engaged in a monitoring programme are likely to be of poor comparability. This in turn can prejudice the conclusions drawn from the results of monitoring. On the basis of previous studies, the problem is known to be particularly acute for measurements of trace metals in saline waters.

Recognising the difficulty, the Marine Pollution Monitoring Management Group (MPMMG) and the Water Research centre (WRc) have organised a programme of Analytical Quality Control (AQC). This has the objective of ensuring that analytical results for filterable cadmium and mercury in saline waters, obtained by water industry and other relevant laboratories, are of adequate accuracy and comparability for their intended uses. WRc is to coordinate a series of tests, some involving distributions of standards and samples, which the participating laboratories undertake; this series of tests, the background to the approach and some of the results obtained to date are described here.
Solute Dispersion and Sediment Transport in Estuaries
Authors: West J. R. , Guymer I. , Sangodoyin Y. , Oduyemi K O. K.
Published: May 2018

Synoptic measurements of velocity and salinity at several points on up to five vertical profiles at a cross-section in the Conwy show that solute dispersion coefficients are affected by secondary flow induced by the interaction of transverse shear and the salinity induced longitudinal density gradient. It is concluded that dispersion coefficients are temporally and spatially dependent and a simple empirical formula is suggested. Some data from the initial stages of a similar study of sediment transport show that techniques exist which permit the study of the turbulent fluctuations of suspended solids concentration and the evaluation of the tidal dependence of suspended solids transport phenomena.
Chemical Fractionation of Heavy Metals in Anoxic Estuarine and Coastal Sediments
Authors: Kersten M. , Förstner U.
Published: May 2018

Chemical extraction experiments for estimating characteristic particulate binding forms of heavy metals in anoxic marine and freshwater sediments were carried out under both the presence and absence of atmospheric oxygen during the analytical procedure. Storage methods including aeration of anoxic sediments do not preserve the initial fractionation patterns of heavy metals and may both increase (Ni, Pb, Cu, Zn, Cd) and decrease (Fe, Mn) their mobility. Elutriate tests of methanogenic freshwater sediments from Hamburg harbour basins show that metals with increased carbonatic fractions (Fe, Hn) and those with predominantly sulphidic/organic fractions (Zn, Cu, Cd) are particularly sensitive to sample aeration. Transformations of oxidizable Ni (11%), Zn (62%), and Cd (67%) predominantly lead to easily reducible associations. Drying of the sediments decreases the proportion of the sulphidic/organic fraction of the metals to a stronger degree. Oxidized Zn and Cd is then found even in the least stable exchangeable fraction. If pretreatment of sediment samples is done adequately the chemical leaching approach may provide information on diagenetic effects and reaction kinetics, which influence the mobility of contaminants in highly complex matrices.
Steady State and Time-Varying Water Quality Models for the Hooghly Estuary, India
Authors: Bose S. K. , Dutta B. K.
Published: May 2018

Steady state and time-varying water quality models for the Hooghly estuary have been developed for the 92.5 km stretch from Tribeni to Mayapur. A hydraulic model of the estuary was previously developed in this connection, based on a simulated channel of trapezoidal cross-section, gradually increasing downstream, and with uniform ground slope. The estuary has also been assumed to be section-ally homogeneous in each of the thirty-seven sections. The advection-diffusion equations have been numerically integrated to compute the instantaneous and time-averaged distribution of BOD and DO. The monthly averages of the quantities over the year have also been determined. The different system parameters have been estimated using available equations and correlations. The calculated BOD and DO values agree reasonably well with the available field data. The study shows that a water quality model based on simulated channel geometry may work well and is useful where a more rigorous hydrodynamic model is difficult to construct and verify.
Evolution of Low Technology Waste Water Disposal in the Developed Countries and Its Implication for the Developing Nations
Authors: Seabloom Robert W. , Carlson Dale A.
Published: May 2018

The majority of people in developing countries are without reasonable access to safe drinking water and are forced to live without proper sanitation. This lack of safe water and poor sanitation is the major cause of untold misery, disability, disease and death. The United Nations declared the 1980's as the “International Drinking Water Supply and Sanitation Decade” with the lofty goal of safe water and adequate sanitation for all by 1990. Realizing it required about 150 years for sanitation systems to evolve in the developed nations, it is important that the developing nations learn from their mistakes. The future sanitation systems for developing countries must use appropriate low cost technologies, rather than the conventional high cost water carriage sewerage technology of the developed nations. These low cost solutions when properly sited, designed, constructed and maintained are no less prestigious and as the overall environmental impacts become understood are in many instances the preferred solution.
The People Who Get in the Way: Changing Values in Urban Waste Management
Authors: Furedy Christine
Published: May 2018

The need for better understanding of “sociocultural factors”--behaviours and attitudes--is recognized as important to advances in waste disposal and treatment for developing countries. This understanding must include the views of planners and administrators and not merely the recipients of basic services. This paper focuses on issues related to waste reuse in cities. It is argued that there must be more research on informal waste treatment and use as customary practices (e.g. in aquaculture and urban agriculture) may form the basis for integrating reuse into community disposal and treatment. This will require changes in the attitudes of officials who often disregard established practices. Adapting informal waste reuse to urban development will raise difficult policy issues that social and medical research may clarify but will not necessarily resolve. Examples are drawn from Calcutta and Lucknow.
Night Soil for Biogas – from Asia to Africa
Authors: Kyu I. , Muturi G.
Published: May 2018

putting human waste into productive use is considered to be part of its effective management. While the increasing demand for fuelwood, leading to deforestation, is getting serious in Africa, the technology of generating biogas from night soil along with animal wastes as an alternative household fuel appears to be most promising. In this regard, there is a need to integrate advanced Asian biogas technology into African practices of living and farming. The present study is firstly based on a literature survey to review and evaluate the various Asian biogas models so as to identify the technology most suitable to African countries while taking into consideration local materials and skills available. In applying the biogas technology, cost of construction appears to be the most important concern and emphasis is given to the development of a system which is not only technically sound but also cost-saving. Social factors are also important for further spreading of the technology, and these are analysed as to the sequence required for successful implementation.
Treatment Characteristics of the Two Phase Anaerobic Digestion System Using an Upflow Filter
Authors: Tanaka S. , Matsuo T.
Published: May 2018

The treatment characteristics of dilute milk wastes (1500 mg COD/l) were investigated by the two phase anaerobic digestion system consisting of a completely mixed reactor for acidogenesis and an upflow filter for methanogenesis. The system removed 92% of the influent COD at an overall hydraulic detention time of 4.4 days. Carbohydrates in the milk were most extensively decomposed (95%), next proteins (50%), while lipids were rapidly hydrolized to long-chain fatty acids but not degraded during the acid phase. The phase separation had an effect on reducing the toxicity of long-chain fatty acids to both acetogenic and methanogenic bacteria. The rates of sludge production were 0.257 mg VS/mg COD utilized during the acid phase and 0.043 mg VS/mg COD utilized during the methane phase. This low sludge production in the methane filter made possible long periods of operation without sludge wasting. The system proposed in this study could accept shock loads of a three-fold increase of the influent COD.
Adsorption of Coliphages to Particulates
Authors: Ohgaki S. , Ketratanakul A. , Suddevgrai S. , Prasertsom U. , Suthienkul O.
Published: May 2018

Adsorption characteristics of coliphages (host cell: E. coli B) to particulates (kaolin, sand, soil, microbial particulates in an oxidation pond) were investigated using batch experiments under various conditions of pH, concentrations of cations and concentrations of dissolved oxygen. The coliphages showed no resistance to acid (pH 3) and weak resistance to alkali (pH 10). Under neutral pH conditions, sodium ions did not have a large effect on the adsorption of coliphages to the solid surfaces of sand. Divalent cations (Mg++, Ca++) had no effect on the adsorption to sand at concentrations below 0.01 mol/l but some effect at 0.05 and 0.1 mol/l. The presence of kaolin had very little effect on removal of coliphages from the water phase under any conditions. Formation of floes such as Mg-hydroxides in alkaline conditions enhanced coliphage removal from the water phase. Coliphage chemical adsorption to particulates in natural waters would probably be low except in estuarine and sea waters. However, the adsorption of coliphages to microbial particulates occurred in aerobic conditions. The desorption of coliphages was observed under anaerobic conditions. This adsorption-desorption process was reversible. The biological adsorption appears to be the dominating cause of coliphage adsorption in natural waters containing microbial particulates.
Intensification of Activated Sludge Waste Water Treatment
Authors: Donáth-Jobbágy A. , Káimán J. , Hajós R.
Published: May 2018

The efficiency of two possible intensification methods of activated sludge waste water treatment (pure oxygen activation and activated carbon addition) were compared. Experiments were carried out in laboratory scale equipment with variable reactor volume (maximum capacity 20,0 dm3, settling tank vol. 15 dm3). In order to detect even minor differences, we operated completely identical units in parallel runs, with one representing a traditional system as reference. A model sewage of industrial character, diluted milk, was used as influent and in the course of activated carbon intensification experiments an anion-active detergent was added as a poorly biodegradable model material to be removed mainly by adsorption. Reactor loads were gradually increased - from low values to overloading - by decreasing the dilution of milk or by reducing reactor volume. The effects of different intensification methods on the effluent pollution level (COD value and anion-active detergent content) and on the settling properties of sludge were examined as a function of loading. The efficiency of both intensification methods was found to be increasing with increasing loading. Comparison of the two systems showed activated carbon intensification to be more efficient in the removal of soluble COD and extremely useful in the elimination of a poorly biodegradable material.
Aspects of Land Disposal of Wastewater as Experienced in Germany
Authors: Boll Reiner , Dernbach Heribert , Kayser Rolf
Published: May 2018

The largest wastewater land treatment facility in operation in the Federal Republic of Germany is located in Braunschweig (Lower Saxony) and serves a population of about 290,000. The treatment process consists of three main components: a pre-treatment plant as an activated sludge process, a sprinkler irrigation area of 3,000 ha of farmland and an old sewage farm of 180 ha with surface flooding. This paper briefly summarizes the experiences with management and operation of the system, the treatment results with reference to environmental impact, development of agriculture and some financial aspects.
Wastewater Treatment by Soil-Covered Contact Aeration Apparatus under Extremely Low Air Temperatures
Authors: Matsumoto Genki I. , Fujisawa Eiji , Kimura Syojiro , Saito Ryoichi , Takayama Tsutomu , Nakamura Syuichi
Published: May 2018

Soil-covered wastewater treatment systems have progressively been used during this decade both in the rural and urban areas in Japan. In order to evaluate the influences of extremely low air temperatures on the covered soil and sewage temperatures, the pressure of contact aeration tank and the treatment of wastewater, we compared the efficiencies of three types of contact aeration apparatus (sewage surface level, 30, 50, 70 cm from the soil surface; top shape of gravel layer, convex, flat; soil-sewage boundary, contact, separate) being packed with gravels as a contact medium and set in the temperature controlled test laboratory. At extremely low air temperatures, the covered soils and ice columns on the surface soils are important as a heat insulator. Freezing depths of soils were inversely correlated with sewage surface levels. The influences of soil freezing on the pressure of aeration tanks were negligibly small and thus soil freezing does not affect aeration systems. No significant changes in the sewage treatment functions among the three apparatus were found. The soil-covered wastewater treatment systems must be useful in cold districts.
Field Studies on the Behaviour of Organic Micropollutants During Infiltration of River Water to Ground Water
Authors: Schaffner C. , Ahel M. , Giger W.
Published: May 2018

The fate of organic micropollutants during ground water infiltration is of great interest since many water works use bank filtration as a first step in the treatment of river water for public water supplies. Field and laboratory studies are necessary to enhance our knowledge on the behaviour of organic chemicals during infiltration of river water to ground water. In an earlier study nonpolar volatile compounds (e.g. tetrachloroethylene, 1,4-dichlorobenzene and 1,3-dimethylbenzene) were investigated in natural river-ground water infiltration systems in Switzerland (Schwarzenbach et al., 1983). In this poster we report on recent work using one of these field sites and studying pentachlorophenol (PCP), nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), nonylphenol diethoxylate (NP2EO) and nitrilotriacetate (NTA), Preliminary results will also be reported for ethylenediaminetetraacetate (EDTA) and polycyclic aromatic hydrocarbons.

The field site for our investigation was in the lower Glatt Valley, Switzerland where the Glatt River infiltrates into a quarternary fluvioglacial valley fill aquifer. The Glatt River is a small, rather heavily polluted perialpine river which receives effluents from ten mechanical-biological treatment plants of municipal waste water (Ahel et al., 1984). At the field site the average discharge of the river is approximately 8 m3/sec and permanent infiltration of the river through a saturated zone can be assumed. Observation wells allowed the sampling of freshly infiltrated water at various distances (2,5 - 14 m) from the river. During one year seventeen sample series were collected at approximately monthly intervals including samples from the river and from four ground water observation wells.

Pentachlorophenol was determined by a method based on the procedure by Renberg and Lindstróm (1981), Detailed descriptions of the analytical methods for NP, NP1EO, NP2EO and NTA are given elsewhere (Ahel and Giger, 1985; Schaffner and Giger, 1984).

The observed averages and ranges of concentrations are given in Table 1. It was concluded that NTA is eliminated rapidly during ground water infiltration. Starting from a range of 8 to 83 mg/m3 and an average of 27 mg/m3 in the river, after 7 m of infiltration only 0.5 mg/m3 are left corresponding to an elimination of 98%. Low temperatures in winter (4 – 6 °C) and reduced oxygen contents in summer had no effect on the efficient elimination of NTA, This result is highly important in addressing the question as to what extent NTA might reach bank filtrated waters from polluted rivers.

The phenolic pollutants were eliminated according to the sequence: NP1EO ≈ NP2EO > NP > PCP. This is based on the decrease of the average concentrations over the first seven meters of infiltration. In particular, PCP turned out to be rather persistent in the ground water but not to such a degree as tetrachloroethylene and other chlorinated solvents which had been studied earlier.
Computerized Water Monitoring and Data-Transmission System for Hydrology, Control, and Management
Authors: Ottmann E J. E. , Vetter K. E.
Published: May 2018

For many water affairs and objectives the following functions are often of great importance:–automatic and continuous measurement of parameter and control and regulation of variables–digital acquisition of data, processing, and storage of data in-situ–quick and safe teletransmission of data to a computing or service centre.

Thanks to computer-aided data acquisition and automated stations, today these functions can be performed in a cost-effective way. Furthermore, it is possible to profit by the efficiency and availability of such systems for a variety of projects in the field of water management.

The paper describes a modern microprocessor-controlled and modular system of CMOS-technology, developed in the Federal Republic of Germany and widely used by authorities and in industry. An outstanding feature of the system is its great flexibility in the range of data acquisition and data teletransmission with the following possibilities:–data collection system (data logger)–data transmission via fixed linesvia telephone linesvia radio.

Several examples show the application with hydrographs and water quality measurements, for the technical surveillance of waters and installations, as well as for the control and management of dams in view of drinking-water supply or agricultural irrigation, respectively. By means of these facilities on the basis of the measuring results, and after examination and evaluation of the information, topical decisions can be made which are founded on relevant strategies or model calculations. The use of the robust equipment is not only recommended for water authorities in industrialized countries, but also in developing countries for integrated measurement and information systems.
Two Stage Sludge Stabilization
Authors: Dichtl N. J.
Published: May 2018

For the stabilization of sludges, theoretical considerations were used to determine a multiple stage ‘Method of Procedure', in order to estimate the advantages and disadvantages of such a procedure. For the procedure, combinations of mesophilic digestion with preceding aerobic-thermophilic or aerobic-mesophilic preliminary treatment as well as anaerobic-thermophilic preliminary treatment, were carried out at a technical pilot scale, in order to quantify the expected advantages compared to one-stage mesophilic digestion. It appeared that, depending on the aim of the process, a two-stage or combined method would give clear advantages either in respect of minimized residence time and desired disinfection, or in respect of all costs for the process.
Fate of Heavy Metals in Sludge Disposal Landspread Operation – A Case History
Authors: Ganze C. W. , Wahlstrom J. S. , Turner D. R.
Published: May 2018

Land treatment of waste biological solids (sludge) has been practiced many years and there have been many studies conducted to determine the applicability of this disposal technique. This paper is based upon an investigation which was conducted to determine if the heavy metals which are associated with sludge are stabilized and contained within a landspread area where no agricultural crops are grown. Sludge/soil mixture samples were analyzed for heavy metal concentrations and cation exchange capacity (CEC) on a routine basis to determine if the heavy metals were remaining in an insoluble form. Groundwater samples and rainfall runoff samples were also analyzed for heavy metals to determine if the metals were solubilizing and being transported into either the groundwater or back to the wastewater treatment process in the rainfall runoff. Analytical results indicate that most of the heavy metals in sludge applied to this landspread area are in a stable form and those that do enter solution are absorbed by the native clay soils and do not contaminate groundwater or upset the biological wastewater treatment process when rainfall runoff is treated.
Alternatives for Soil Disposal of Excess Activated Sludge from the Industrial Waste Treatment Plant at Companhia Alcoolquímica Nacional
Authors: Francisco R. , Scheleuderer J. , Venturelli S. S. , da Rocha G. C.
Published: May 2018

The industrial wastewater treatment plant at Companhia Alcoolquímica Nacional in Cabo, PE, with operation start-up expected in the second semester of 1986, is composed of: hydraulic and organic load equalization, pH correction and an extended aeration activated sludge plant. For the purpose of disposing of 995 kg solids/day (dry solids) excess biological sludge, a study was undertaken with the intention of using land disposal, after preliminary comparison with other conventional methods.

For the disposal of this sludge, which was thickened to 4% suspended solids by dissolved air flotation, two alternatives were proposed:Land disposal by subsurface injection (10 t dry solids per hectare per pass every 60 days).Land disposal by the trench fill system, in an available area of 3 ha.

In the case of subsurface injection, grass would be used for the vegetation cover. In the case of the trench fill system, corn and/or manioc tillages would be used. The crops obtained from these tillages may be used for animal feed.

After analysing several factors, such as available area, implementation and operating costs, handling facilities and climatic conditions, the trench fill disposal system was chosen. This has the following features:(a)Trenches with 50 cm base, distance from one trench to the next of 100 cm, (i.e., 10 trenches per 15 m), 35 cm depth;(b)0.3% trench slopes;(c)Conveyance of thickened sludge through a main chute with 0.1% slope;(d)120 t dry solids/ha/yr application, on a 3 ha total area;(e)Addition accomplished at a rate of 1/5 ha/day (5 days per week), the whole cycle being completed every three weeks.
Agronomic Requirements for Soil Utilization in Liquid Waste Disposal Systems – The Case of Sitel
Authors: Simon Zeno , Tedesco Marino
Published: May 2018

At SITEL – the integrated effluent treatment system of Pólo Petroquímico do Sul (South Petrochemical Complex), Triunfo, State of Rio Grande do Sul, Brazil – both the final effluent and the thickened excess activated sludge are disposed of on land. Thorough agronomic investigations made possible the identification of appropriate soils for receiving the wastes and the establishment of some design criteria. Profile depth, texture, infiltration rate, internal drainage, slope and availability of land covered with intact vegetation were the main factors considered in the election of areas for effluent disposal. For sludge application the following factors were taken into account: drainage, slope, chemical characteristics (mainly pH and Organic Matter), distance to the sludge loading point, suitability to agronomic management, ease of access, topography and presence of an adequate grass species (pangola grass).

The results of the preliminary agronomic investigations are presented and discussed. Design assumptions are confronted with actual operational data. Comparisons are made with other reported situations. A discussion on the limitations, shortcomings and incompleteness of the available criteria and guidelines is included, with particular focus on CEC, Infiltration Rates, Maximum Permissible Loadings, Nitrogen and Organic Matter.
Tejo 1– An Interactive Program for the Division of Estuaries into Homogeneous Areas
Authors: Câmara A. S. , da Silva M. Cardoso , Ramos L. , Gomes Ferreira J.
Published: May 2018

The division of an estuary into homogeneous areas from both hydrodynamic and ecological standpoints is essential to any estuarine basin management model. This paper presents an approach based on a heuristic algorithm to achieve such a division. The methodology implemented through an interactive computer program named Tejo 1 applies morphological, water quality and management criteria in order to achieve the disaggregation. The approach is equally applicable to river or lake basins, with only minor adaptations. An application of Tejo 1 to the Tejo estuary is included for illustrative purposes, which resulted in the final division of the estuary into 11 homogeneous areas.
Use of Geographic Information Systems (GIS) in River Basin Management
Authors: Goulter I. C. , Forrest D.
Published: May 2018

Geographic Information Systems (GIS) are shown to provide a number of capabilities which are of particular use to river basin operation and planning. GIS systems have the ability to display and graphically summarize both the input data for the analytical models and the results of application of management models using that data. The graphical display of input data can assist interpretation of conditions within the basin through depiction of spatial and temporal patterns in that data. GIS can also reduce the time required to enter data and improve the reliability of that data by reducing the errors in the data. The ability to display the results graphically improves the man-machine interaction which is generally accepted as being an integral part of multi-objective water resources analysis. Another important role for GIS is its use as an efficient interface between the data base and the operational computer models. It is asserted, however, that GIS should not be considered a means of providing final answers to complex water resources planning issues. It should be seen, rather, as an important component of Decision Support Systems by which information on the basin issues is transferred to the decision maker for his consideration. Specific aspects of the application of GIS are discussed in relation to a hypothetical river basin system used primarily for hydroelectric energy generation.
Integrated Water Resource Management in Latin America and the Caribbean: Opportunities and Constraints
Authors: Dourojeanni A. , Nelson M.
Published: May 2018

The virtues of integrated water resource management have been widely extolled in the literature. The purpose of this paper is to review selected aspects of Latin American and Caribbean experience which may provide insights on the constraints and opportunities for progressing towards such integration. Economic development and population growth are placing demands on water which are increasing exponentially. However, with a few exceptions, governments have shown little effective response to the broader issues in resolving the inevitable conflicts. Formulation of plans and policies appears straightforward and it is easier still to recommend implementation by powerful co-ordinating agencies. However, practice bears little relation to theory. This suggests that a focus on questions other than technical optimization might be relevant. Attention needs to be given to the institutional structure - formal and informal rules - which determine why decisions are made at the political, organizational and operational levels resulting in de facto water management. Greater transparency on the informal rules may enable more systematic transactions between and within these three levels (particularly within the organizational level) leading to changes which would allow incorporation of a broader and more long-term view of renewable resource management issues.
Experiences in Water Resources Management in Developed Regions
Authors: Weaver Leo , Tennant Peter A.
Published: May 2018

The science and engineering of water resources in developed countries has undergone profound changes in less than a professional lifetime. This has radically influenced education and research and essentially revolutionized water resource planning. Fundamental uses of water to fulfill society's needs continue. These include domestic and industrial supplies, waterways for transport, fire protection, waste carriage, recreation, irrigation, and in general, an adequate quantity and quality of water in the right place at the right time to fulfill human and aquatic needs. The complexities of water resources no longer may be measured largely in terms of science and engineering challenges alone, but must include economics sensitive to the political and social sciences. What has evolved is what is now best described as water management. This paper reviews the evolvement of water resources management in developed counties in terms of historical background, and national policies and institutions, particularly as this evolvement impacts scientific research and engineering application.
Socio-Economic Development Levels and Adequate Technological Policy for Water Resources Management
Authors: Imhoff K. R.
Published: May 2018

Depending on population density and economic status of the area different technologies for wastewater disposal have been developed. Technologies are presented. Optimal application spectrums are pointed out.
Socio-Economic Development Level and Technology Policies for Water Resources Management
Authors: Tsuzuki Goki
Published: May 2018

Water is considered to be essential for all forms of life. The multiple uses of water and the consequences of its inadequate use, as well as the socio-economic conflicts arising from the inappropriate management of water resources, are discussed. The impact of the marked differences in development between the regions which result from the large size of Brazil must be taken into account. Policy decisions regarding management of water basins will determine the form of participation of the different sectors in water resources use with priority given to human uses for direct consumption and hygiene, and to uses of the soil associated with floods. A variety of methods may be used for data collection, analysis, interpretation and storage. These methods range from manual equipment to large main frame computers. The purpose of the creation of a ‘National System for Water Resources Management' is to organize and institutionalize, whenever necessary, a dynamic and efficient system for the adequate management of water resources.
A High Organic Load Stabilization Pond Using Water Hyacinth – A “Bahia” Experience
Authors: Santos E. J. , Silva E H. B. C. , Fiuza J. M. , Batista T R. O. , Leal P. P.
Published: May 2018

A wastewater treatment pond covered with water hyacinth (Eichhorniacrassipes) was first tested in Bahia in an attempt to treat sewage from an urban area in Salvador, Bahia, Brazil. This pond, which receives a high organic load with an average of 750 kg BOD/ha.day, after a short detention time of as little as 5 days, exhibited a removal rate efficiency of 90.7% of BOD and 96% of suspended solids. The problems related to the operation of this plant and its limitations, mainly regarding removal of nutrients, are discussed.
Aerial Spray of Mosquito Adulticides in a Salt Marsh Environment
Authors: Wang T. C. , Lenahan R. A. , Tucker J. W. , Kadlac T.
Published: May 2018

Aerial applications of organophosphorous pesticides are widely used to control adult mosquito populations in the State of Florida. Because the pesticide may drift into estuarine water and affect non-target organisms, a field study was conducted to determine fenthion, malathion, and naled concentrations and disappearance rates in a salt marsh water body. Concentration normally increased and peaked at .75, .95 and 1.40 hrs after an aerial spray for fenthion, naled and malathion, respectively. The concentration then gradually decreased and after 48 hours, only a trace (≤ 0.01 μg/ℓ) was detected.
The Use of an Algal-Microcrustacean Polyculture System for Domestic Wastewater Treatment
Authors: Kawai H. , Jureidini P. , da Conceição Neto J. , Motter O. F. , Rossetto R.
Published: May 2018

Domestic sewage and some types of agroindustrial waste, although highly polluting wastes, could become important energy and protein sources because they are wastes which contain significant amounts of organic matter and nutrients used by human beings.

Based on this concept, experiments at different scales (laboratory, semi-pilot and pilot) have been carried out to verify the viability of a system composed of an anaerobic pond, an algae pond and a Zooplankton pond for the treatment of domestic sewage and, at the same time, to reuse the Zooplankton as animal feed. Scenedesmus sp and Daphnia sp were introduced into the algae and zoo-plankton ponds, respectively, to be maintained as the predominant biological element.

The best operational performance was obtained when the Zooplankton pond was operated with a semicontinuous flow system, with 50% of the Zooplankton pond water being renewed with effluent from the algae pond every 2 or 3 days.

The productivity of Daphnia sp under these operational conditions reached around 35 mg/l (dry weight). This corresponds to a production of 700 kg of microcrustaceans per day for a city with 100,000 inhabitants.

The BOD removal efficiency obtained during the experiment was 95-97%, and total ? and total ? removals were 42-59% and 37-48%, respectively. The final effluent had high transparency. In the Zooplankton pond, the algae concentration was reduced from 106cells/ml to 102 cells/ml, which corresponds to a removal efficiency of 99.99%.
Chemical Precipitation in Highly Loaded Stabilization Ponds in Cold Climates: Scandinavian Experiences
Authors: Ødegaard H. , Balmer P. , Hanæus J.
Published: May 2018

Results both from a pilot-plant investigation and from full-scale stabilization ponds operating with phosphate precipitation are presented. Since the removal of organic matter by coagulation is more important than that by biodegradation, the ponds may be heavily loaded. Biodegradation, during winter can be improved by pond aeration, and chemical precipitation in an aerated pond may give a very good and stable effluent.
Treatment of Slaughterhouse Wastewaters in Stabilization Ponds
Authors: Duarte A. C. , Arroja L. M. , Diegues P. F. , Rosada I. , Hall A. , Oliveira J. B.
Published: May 2018

A sampling programme was devised to assess in terms of 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and suspended solids (SS) removal the performance of one anaerobic, one facultative and two maturation ponds in series, for treating the wastewaters resulting from a slaughterhouse killing approximately 625 pigs/week. The results show that, in spite of poor maintenance,which has been causing bank erosion and macrophyte infestation, the system has coped with large variations in flow and organic load, reducing to a minimum the impact of the effluent discharge on the receiving creek.
Water Quality Improvement of Secondary Effluent by an Oxidation Pond with Subsequent Sand Filtration Treatment
Authors: Fujii Shigeo , Somiya Isao , Takeda Kaoru
Published: May 2018

A series of oxidation ponds and subsequent sand filtration experiments was performed to improve the water quality of secondary effluent containing organics and nutrients. The results show that the main reaction mechanism in the oxidation pond is the fixation of inorganic nutrients by algae. T-N and T-P concentrations in pond effluent decrease to 80 % and 77 % of influent respectively owing to the sedimentation of the particulate fraction. A sand filtration experiment on the pond effluent was conducted. At a filtration rate higher than 5 m/day, physical filtration mainly takes place, and clogging of the sand filter occurs within 1–3 days. However, at a rate lower than 1 m/day, the process of decomposition of deposits is also observed, and the run length becomes longer (> 20 days). The removal efficiency of SS is very high, ranging from 97 to 100 %. The total removal efficiency by an oxidation pond with sand filtration treatment is 24 to 37 % in T-N and 32 to 75 % in T-P. The most rational filtration rate for good performance seems to be 0.5 m/day because of its long run length. The effect of fish (Rhinogobius brunneus) on this treatment becomes obvious, prolonging the run length by 20 % or more due to feeding on the deposits.