bluuebunny/crossref_metadata_2025 huggingface dataset:
Process Integration in Sludge Management
Authors: Dick R I , Simmons D L , Hasit Y
Published: May 2018

Complex interactions occur between individual sludge treatment processes and other sludge management processes. Sludge treatment processes also interact with wastewater treatment processes. Consideration of those interactions has been facilitated in this work by a computerized optimization scheme using models of process performance and cost based on fundamental design and operational variables.

Illustrations of the type of results obtained are described. It is indicated that the mean cell residence time of activated sludge processes and the retention time of anaerobic digesters should, with current energy costs, be as short as possible while assuring satisfactory operation. The additional cost of larger gravity thickeners is often offset by savings in anaerobic digestion and other process costs. The method by which sludge is transported to a point of ultimate disposal has an important effect on identification of the lowest cost technique for sludge management. Based on available cost information, ocean disposal, where feasible, is nearly always cost effective and sludge combustion is not. The cost of energy significantly affects optimal design of sludge treatment processes.
Theme 4: Technology Transfer: Report of the Session Convenor
Authors: Eberle S H
Published: May 2018

The aspects discussed were scale up problems, the role of participants in the technology transfer process, the need of involvment of practioners in research and planning, packaging of information in technology transfer programmes. It was shown that technology transfer is a complex process with proper scale up or down as the main technical factor and adequate information transfer as well as the involvement of the potential user as main methodical factors. A prerequisite is an end-scaled view in research and development.
Scale-Up Problems
Authors: Sidwick John M
Published: May 2018

The paper considers some of the problems of the scale-up of wastewater treatment processes; from bench-scale to pilot-scale, and from pilot-scale to full-scale. An attempt is made to put the question of scale-up problems into perspective by reference to the experience of the author and the work of others reported in the literature.
Mineralisation Problems in the PWV Complex – The Identification of Viable Solutions by Means of a Suite of Mathematical Models
Authors: Herold C E
Published: May 2018

The Pretoria-Witwatersrand-Vereeniging (PWV) complex, the most economically active region in southern Africa, depends for its water supply upon the Vaal river, which serves also as the sink for much of the pollution emanating from the complex. Over the past 45 years, the annual increase in water demand by the urban consumers has exceeded 7%, and the current rate of growth shows no sign of diminishing. The region is not richly endowed with waer resources and already considerable quantities of water have to be transferred into the Vaal basin from the adjacent Tugela basin.

Mineral pollutant loads, both from point and from diffuse sources, have risen to intolerable levels. With the onset of the rainy season, there is a pronounced “first flush” phenomenon, whereby salts accumulated in the catchment are washed off, causing unacceptably high TDS peaks in the primary water supply source. The problem is compounded by the feed-back effect whereby effluents are recycled into supply with consequent build- up of salinity. Without some form of numerical model it would not have been reasonably possible to plan measures to improve the position.

A suite of numerical models having meteorological data as basic input has been developed. The models simulate at key points in the system, for any demand horizon, monthly or daily salt concentrations associated with a wide variety of alternative management strategies. The models have been successfully calibrated and verified. Incorporated in the models are the economic parameters relating salinity in the water supply to the costs incurred by consumers in having to use water of poor quality. A method has been evolved whereby the costs and benefits to consumers resulting from various water resources and pollution control planning and management options can be objectively compared. Both present-day and probable levels of future pollution and of demand are taken into account in the evaluation of options.
An Overview of Digestion Processes
Authors: Pretorius W A
Published: May 2018

The production of methane in the anaerobic digestion process is brought about by the metabolic activity of a small and highly specialized group of methanogenic bacteria. In this overview the conditions necessary for the growth of these bacteria, the possible extra-cellular substrate flow from complex substrates to methane and different applications of the anaerobic digestion process are discussed.
Recent Developments in Sludge Conditioning and Dewatering
Authors: Cornier J C , Divet L , Moreaud H
Published: May 2018

Government directives and sewage plant managers alike stress the great importance that should be attached to sludge treatment. The main objectives in this respect are:−to cut reagent and energy costs,−to facilitate maintenance and conservation of plant,−to favour sludge utilization.

Some recent examples, representative of these new trends, are outlined below.
South African Practice in Land Disposal of Sludge, Including Legislation and Health Aspects – An Overview
Authors: Oberholster G
Published: May 2018

A Short overview of South African practice in the land disposal of sewage sludge is given, the applicable legislation is cited and guidelines for the agricultural use of sewage sludge are introduced.
Evaluation of the Load of Enteroviruses in a Biological Wastewater Treatment Plant
Authors: Rolland D , Hartemann Ph , Joret J C , Hassen A , Foliguet J M
Published: May 2018

The numbers of enteroviruses, classical bacterial indicators and physico-chemical parameters were recorded for raw and treated wastewaters from the NANCY (FRANCE) activated sludge treatment plant, over 24 and 72 hours periods. Sampling was performed manually by collection of 2 and 3 hour interval dip samples and by sequential automatic samplers. The results obtained with both methods are in good agreement; 24 hours composite samples with automatic sampling are representative of enteroviruses flux and thus allow studies of the efficiency of removal treatments. According to both sampling methods, the efficiency of the NANCY wastewater treatment plant is about 84 % for the removal of indigenous enteric viruses.
Water Quality and the Discharge of Cooling Water into Rivers, Lakes and Coastal Waters
Authors: Gasparini R.
Published: May 2018

This paper resumés some of the main findings and conclusions of a study group on cooling water problems (1) set up by UNIPEDE (2). The paper represents only the personal point of view of the author, in particular as chairman of the above mentioned group. The basic aim of the work was the study of the effects of the discharge of cooling water in the receiving water bodies (rivers, lakes and coastal waters). This type of assessment permits a more balanced and pragmatic approach to aspects such as thermal pollution, entrainment, impingement and pollution by antifouling agents.

The first part of the paper deals with the problem of damage to organisms entering a cooling system. An important factor in assessing the meaning of such aspect is the growing evidence that there is no reduction in fish population of the receiving water body associated with the operation of modern power plants despite the catch in the once through-cooling systems due to entrainment and impingement, that can be minimized, but not avoided.

The second part deals with the different methods of fouling prevention in power plants, with their possible environmental effects in the receiving water bodies.

The third part is a comprehensive review of the results of aquatic impact studies at power plants, that is the results of many experimental investigations carried out in the field to evaluate the effects of the operation of once through cooling systems sited on rivers, lakes, or coastal waters.
Biological Monitoring of Thermal Effects of Cooling Water Discharges from Danish Power Plants
Authors: Møller Bo , Dahl-Madsen K I
Published: May 2018

In the years from 1970-1982 52 site studies and monitoring studies have been carried out at major existing and planned power plants. The results from the studies have been used in a planning system for water quality. This planning system, which is water quality related, is described in this paper. An important part of the planning system is the description of size and distribution of excess temperature fields and the related biological conditions.

In the biological monitoring, emphasis is placed on the benthic community as more vulnerable to the cooling water discharge. The studies have shown that the excess temperature field within the 1-2° isotherm can produce measurable changes in the benthic community.

The temperature effect in the pelagic zone is marginal, however, some effects are seen at sites with a deep water intake of nutrient rich water. Entrainment of fish and Zooplankton can be important in bays and estuaries.
Decomposition and Transport of Monochloramine in Fresh Water
Authors: Lin Yia-S , Kim Byung R , Bell Tracey L , Ruane R J
Published: May 2018

Chlorinated effluents from cooling water condensers and wastewater treatment plants enter receiving streams and can affect aquatic organisms. The kinetics for dissipation of chlorine residuals (primarily monochloramine) in water under different light conditions (dark, sunlight, and UV light) were investigated by conducting a series of closed batch studies and found to be first-order with respect to monochloramine concentration. This kinetic information was then incorporated into a two-dimensional transport model to describe concentration profiles in a river by considering the decay reaction, mixing, and dispersion, and by approximating the river as a straight rectangular channel. According to predictions of chlorine residual persistence, chlorination at night could have more impact on aquatic life than that during the day.
Analysis of Effluents and Receiving Waters Arising from the Coal Fired Kasimpur Thermal Power Plant
Authors: Ajmal Mohammad , Nomani Azhar A , Khan Mujahid A
Published: May 2018

The waters of the upper Ganga canal, discharged cooling water and the machine washings of 530 MW Kasimpur coal fired thermal power plant were analysed for different parameters like colour, turbidity, pH, total alkalinity, total dissolved solids, chloride, sulphate, nitrite, nitrate, nitrate-ammonia, dissolved oxygen, biochemical oxygen demand and chemical oxygen demand. Metals zinc, lead, cadmium, iron, chromium, copper, nickel, cobalt and manganese were also determined in upstream, down stream, discharged cooling water, machine washings, sediment, plant and fish of the canal. The concentrations of Zn, Pb, Cd, Fe, Cr, Cu, Ni, Co and Mn in the upstream, downstream, cooling effluent and machine washings were found in the range 44.4-204, 1.33-26, 0.27-1.7, 49-208, 13.52-176. 11.5-79, 4.1-9, 4-8.1 and 42-68 µg/l; in the sediments 56.4-133, 1.22-28, 0.8-1.6, 9438-10595, 14.2-128, 13.6-15.0, 18.4-21, 7.3-16 and 320.7-392.2 µg/g; in the plants 21-25, 1.3-2.3, 0.05-0.08, 422-504, 3.5-11, 6.7-11.6, 3.3-7.9, 5.1-10.7 and 81-119 µg/g and in the fish 129.2-141.4, 2.1-3.82, 0.023-0.028, 234-242.1, 1.3-2, 7.8-11.3, 2.2-2.9, 2.6-3.0 and 108-114.6 ég/g on a dry weight basis. The sediments of the canal were analysed for pH, calcium carbonate, organic matter, potassium and phosphorus.

In addition, the effects of influent and effluent water on the physico-chemical properties of soil, germination of seeds and growth pattern of the plants were observed but the results were found to be insignificant.
Radiochemical Techniques Applied to Laboratory Studies of Water Leaching of Heavy Metals from Coal Fly Ash
Authors: Goetz L
Published: May 2018

Assessment of the potential environmental impact of heavy metals (HM) mobilized by coal-fired power plants showed that water leaching of HM from pulverized fuel ash may for certain HM constitute an important pathway to the aquatic environment. This process was therefore investigated in more detail by laboratory experiments. Batch experiments were performed in order to simulate ash pond conditions, whereas column experiments were carried out to represent water leaching from fly ash deposits. Using highly sensitive radiochemical techniques such as radioactive tracers and neutron activation of fly ash the fate of a single HM could be easily followed even in very low concentration experiments. Employing radioisotopic tracers the distribution coefficients of simple ionic forms of As, Sb, Bi, Se, Te, Cr, Mo, W, Ni, Cd in a coal fly ash/water system could be determined as a function of pH. Results obtained on the adsorption and desorption behaviour of HM on coal fly ash can be explained in part on the basis of the surface predominance and the aqueous chemistry of single ionic, mainly anionic, forms of the relative elements. But ion exchange and coprecipitation phenomena also seem to be important processes. The nature and concentration of ions contained originally in the water used (distilled water, fly ash leachate and seawater) were found to have a strong influence on the sorptive behaviour of HM on coal ashes. The high degree of applicability of radiochemical and nuclear techniques to coal ash water leaching problems has been demonstrated and further points for subsequent research in this field possibly using nuclear techniques are indicated.
Disposal of Waste Material – Evaluation in the KHM Project of Short and Long-Term Effects
Authors: Hartl Janén , Lundgren Tom
Published: May 2018

One of the main objectives of the Swedish Coal-Health-Environment Project is to assess the short and long term effects of the disposal of coal wastes on the environment. The situation described below has been the basis for the discussions, laboratory leaching tests and field studies carried out in the KHM Project. The results of the laboratory works are reported to the conference in a paper by Liem et al, while this paper discusses the water balance and construction measures.

Certain trace elements in coal wastes are found in greater concentrations than in normal soils and rocks. As a result of the mineral alteration in the combustion process the mobility of some of the constituents may be higher in the waste than in the coal (or in sediments in general). On the other hand the alkaline properties of the waste reduce the mobility of many elements. Due to the continuous leaching out of buffering substances the pH of the leachate water will vary with time. The construction of trace elements in the leachate from a waste dump, exposed to acid rain, is governed by several factors. Beside the trace element composition and the leaching characteristic of the waste, the buffering capacity, the time and the water balance of the dump are judged to be the main controlling factors.
Marine Disposal of Fly Ash from Coal Fired Power Plants
Authors: Hjelmar Ole
Published: May 2018

In order to obtain an evaluation of the environmental impact of a proposed artificial marine island of deposited fly ash a comprehensive research project has been carried out by the Water Quality Institute in cooperation with other institutes. The project involved a number of field investigations designed to yield the information required to predict emissions and ensuing ecotoxicological effects of such an island. This paper treats some project activities which were performed in pursuit of data needed for estimating emissions from various stages of a marine ash island: Dry fly ash characterization, monitoring of operating ash ponds, investigations at old ash ponds, and laboratory leaching test. The results may be used to describe and evaluate emissions from various forms of marine fly ash disposal.
Dust Emission, Its Quantity and Composition, Depending on Dust Collector, Coal Quality and Other Factors
Authors: Falster Hans , Jacobsen Lars
Published: May 2018

Dust emission measurements have been carried through at Danish coal-fired power stations. Investigations show that modern electrostatic precipitators can meet Danish emission standards even for high resistivity ash.

Modern electrostatic precipitators can reduce particulate emissions with a factor 10-20 compared to older precipitators.

Trace metals that are very strongly attached to the finest particulates (As, Cd, Mo, Pb etc.) show less reduction in emission.
Background to Biological Phosphorus Removal
Authors: Barnard James L
Published: May 2018

This paper briefly summarizes the early work on phosphorus removal in activated sludge plants in the U.S.A. and observed that such removals only occurred in low SRT plants of the plug flow type and in the Phostrip plants, neither designed for full nitrification. The discovery of simultaneous nitrogen and phosphorus removal, as well as full-scale experiments are discussed. The Phoredox process was proposed utilizing internal recycling for the removal of nitrates and an anaerobic first stage in which the incoming feed is used to obtain the necessary anaerobic conditions, essential as a conditioning step for the uptake of phosphorus. Proposed mechanisms are discussed.
The Role of Micro-Organisms Other than Acinetobacter in Biological Phosphate Removal in Activated Sludge Processes
Authors: Brodisch Karin E U , Joyner Sylvia J
Published: May 2018

The composition of the microflora in the anaerobic, anoxic and aerated stages was determined by means of the Analytical Profile Index (API) system for three biological phosphate removal plants (a pilot plant (capacity 100 m3/d) and two laboratory scale units (capacity 24 ℓ/d)). The plants monitored differed with respect to anaerobic retention time and configuration, but all three were removing phosphate to concentrations less than 0.2 mg/ℓ as P during the experimental period. In contrast to findings by other investigators, bacteria of the genus Acinetobacter were present in minor proportions. Organisms of the genera Aeromonas and Pseudomonas constituted more than 50 % of the total aerobic microbial population. Depending on the length of the anaerobic retention time, 40 to 50 % of the bacteria were identified as Gram-positive. These findings suggest that Acinetobacter species may not be the only bacterium to remove phosphate from an activated sludge system, but that other groups of bacteria also do so under suitable environmental conditions.
Full Scale Phosphate Removal Experiences in the Umhlatuzana Works at Different Sludge Ages
Authors: Kerdachi D A , Roberts M R
Published: May 2018

This paper describes full-scale phosphate removal at 69, 38 and 8 day sludge ages. The results of operation at 20 days are also mentioned, but were not monitored intensively. Exceptionally good results were obtained treating an unsettled domestic wastewater in a simple activated sludge plant, under optimum operating conditions in a soft water region. At sludge ages of 69 and 38 days, more than 92% of the influent carbon, nitrogen and phosphorus were removed simultaneously and consistently without chemical addition or tertiary treatment.

The Authors attribute the extra-ordinarily high efficiency of phosphate removal to the functioning of two mechanisms which complement one another. There is sufficient practical evidence to suggest that the low concentration of residual phosphate is governed by the equilibrium kinetics of a solid phosphate phase and not by micro-organisms. Major findings have been that restricted oxygen input is associated with efficient phosphate removal and that it is possible to condition activated sludge anaerobically so that its behaviour changes gradually from the anaerobic phosphate release regime associated with luxury uptake by Acinetobacter to a regime of insignificant phosphate release associated with the most efficient phosphate removal.
Tainted Fish Caused by Petroleum Compounds – A Review
Authors: Motohiro T
Published: May 2018

A number of compounds present in petroleum can produce an oily flavour in fish. These are saturated and unsaturated paraffins, aromatic hydrocarbons and sulphur compounds. The intensity of oily flavour to some extent depends upon type, number of carbons and molecular structure of causative hydrocarbons. The qualitative and quantitative analyses indicate that there are many different types of petroleum compounds to which off-flavours are attributed, since feeding behaviour to oil tainted food, differs with species of aquatic organisms. Benzothiophene, toluene, xylene and benzene may not only produce an oily flavour in fish, but also they inhibit the enzyme reactions in the energy transfer system. Methionine synthesis in fresh sea weeds can also be inhibited as indicated by lower levels of dimethyl-β-propiothetin in sea weeds grown on the oiled rock.
Stripping Techniques for the Analysis of Odourous Compounds in Drinking Water
Authors: Sävenhed R , Borén H , Grimvall A , Tjeder A
Published: May 2018

To develop a systematic procedure for the identification of odourous organic compounds in drinking water Grob's stripping method was modified to improve the concentration of odourous compounds. Sensory analysis of stripped waters and concentrates of stripped compounds showed that the yield of odourous compounds increased substantially at elevated stripping temperatures and prolonged stripping times. Chemical analysis showed an increased recovery of semipolar compounds, e.g. aldehydes, ketones and alcohols. The change from a closed loop to an open stripping system has greatly simplified stripping analysis at higher temperatures. Raw and treated surface waters have been analysed. Capillary gas chromatography and mass spectrometry were used for the separation and identification.
Production of 2-Methyliso-Borneol by Two Benthic Cyanophyta
Authors: Izaguirre G , Hwang C J , Krasner S W , McGuire M J
Published: May 2018

Two Oscillatoria strains have been isolated from three different water supply systems in California that have experienced taste and odor problems in their drinking water. The algae were obtained from sediment samples and rock scrapings from source-water reservoirs. Unialgal cultures, free of actinomycetes, were purged using the closed-loop stripping analysis method, and the resulting extracts were analyzed by gas chromatography and mass spectrometry. The organisms, Oscillatoriacurviceps and O.tenuis variant levis Gardner, yielded 2-methylisoborneol (MIB) at 60–150 µg/l. In both instances, MIB had previously been identified in the sediment samples from which the organisms were isolated. O.curviceps was implicated in a taste and odor episode involving MIB in a major reservoir during two consecutive summers.
A Comparison of the Anaerobic Filter and the Anaerobic Expanded/Fluidized Bed Processes
Authors: Switzenbaum M S
Published: May 2018

The anaerobic filter and the anaerobic expanded/fluidized bed processes represent advances in wastewater treatment technology for processing organic wastes. Literature data for both processes is presented and discussed. In addition, mass transport concepts are used to compare the substrate flux rates of both systems. It is concluded that the expanded/fluidized bed represents a more efficient design for anaerobic fermentation reactions.
Mercury Mobilization and Toxicity in Marine Microbial Food Chains
Authors: Berk S G , Colwell R R
Published: May 2018

Transfer and accumulation of mercury were observed to occur in a three-component estuarine food web comprising bacteria, ciliated protozoa and copepods. Results of experiments designed to test trophic interactions revealed significant feeding of each predator on its prey. Two bacterial species readily accumulated mercury from media amended with 203HgCl2, with the Vibrio sp. accumulating more mercury at low initial concentrations than the Pseudomonas sp., even though the Vibrio sp. was less tolerant to elevated concentrations of mercury. The labeled bacteria were fed to the ciliate, Uronema nigrioans, and mercury transfer was monitored by liquid scintillation counting. The mercury concentration in protozoa was observed to be greater than that of the individual bacteria on which they fed, demonstrating magnification of the mercury concentration in the higher trophic level.

When labeled ciliates were fed to the copepod, Eurytemoxn affinis, the mercury concentration in the copepods was less than that of the ciliates, although greater than the initial concentration in the bacterial medium, indicating magnification above background level in the copepod. When sterile kaolinite clay to which 203HgCl2 had been added was fed to copepods, mercury transfer and retention in the copepods resulted, indicating that, in addition to biologically mediated uptake, non-biological transfer to and accumulation in copepods also occur.

The ciliates were found to acquire tolerance to mercury after being fed mercury-laden bacteria followed by exposure of washed suspensions of these ciliates to various concentrations of mercury in solution. The phenomenon of acquired mercury tolerance was demonstrated within a single generation time. Ciliates fed mercury-free bacteria and subsequently exposed to increasing levels of mercury in solution showed an elevated tolerance to concentrations which, on initial testing, resulted in mortality of 83% of the population. The effect of ingesting mercury-laden bacteria on growth rate of Uronema was examined, and results showed no significant differences in growth rates of both 3- and 14-day-old cultures of protozoa that had been fed mercury-laden and mercury-free bacteria. Ecological implications of acquired metal tolerance and use of ciliates as indicator organisms are discussed.
Water Requirements and Conservation Alternatives for Northern Communities
Authors: Armstrong B C , Smith D W , Cameron J J
Published: May 2018

This paper reviews water requirements and the alternatives for water conservation in small, relatively remote northern communities. Requirements are examined in terms of basic needs and desires for sanitation from an individual household and a community perspective. Presented are factors which influence water use such as the method of delivery, household plumbing, socio-economic aspects, rate structure, climate and plumbing codes. Similarly, factors which influence water conservation are identified. Outlined in detail are current methods of reducing water use within the northern household.
The Formation and Control of Trihalomethanes in Water Treatment Processes
Authors: Peters C J , Perry R
Published: May 2018

The occurrence and formation of trihalomethanes in water supplies in relation to source waters and treatment practice are evaluated. Factors influencing their formation are discussed with reference to detailed laboratory studies involving humic and fulvic materials as well as model compounds. The influence of temperature, pH and chlorine dose is related to the rate and mechanism of formation of these compounds and a direct aqueous injection analytical technique is used to evaluate the significance of unstable intermediate compounds formed. Bromide levels in the source waters are related to the balance of trihalomethanes produced during chlorination.
Greywater Characteristics, Health Concerns and Treatment Technology
Authors: Hrudey S E , Raniga S
Published: May 2018

Greywater chemical and microbiological characteristics are reviewed. Potential relationships between inadequate greywater disposal and poor community health in isolated northern settlements are considered. Greywater treatment technology is discussed and criteria are developed for application in isolated northern communities.
Treatment Alternatives for Dilute, Low Temperature Wastewater
Authors: Smith D W , Given P W
Published: May 2018

Deep frost penetration or permafrost soils have led to a number of alternative methods for the distribution of water and collection of wastewater. One of the earliest approaches was to assure that flow was maintained in the pipes by continuous bleeding. The resulting wastewater being dilute and cold presents an interesting treatment problem. The paper briefly reviews cold, dilute wastewater treatment using lagoons, rotating biological contactors (RBC), extended aeration and physical/chemical methods of treatment. Results of more extensive studies on an RBC and a screen/ozone system are presented in more detail. Factors which influence the selection of a treatment process are reviewed.
Sludge Dewatering with Filter Presses and Centrifuge Followed by Sludge Incineration at the Wastewater Treatment Plant Düsseldorf-Nord, F.R.G.
Authors: Kuhlmann H
Published: May 2018

The wastewater of approx. 800 000 inhabitants and population equivalents is treated at the mechanical aeration wastewater treatment plant Düsseldorf-Nord. The dry-weather flow amounts to 145 000m3/d, of which 40 % is industrial waste water.

The combined sludge-primary sludge from the mechanical part and waste-activated sludge from the final settling tanks has been anaerobically stabilized, then chemically conditioned, dewatered in filter presses and to a large extent used agriculturally. Satisfactory performance could be obtained with this type of sludge treatment and no special problems occurred. As agricultural use has become more restricted due to new laws on sludges from treatment processes, and no adequate land-fill is available, the present plant has been expanded by a multiple hearth incinerator, to minimize the sludge volume. At the same time, a centrifuge, after which the dewatered sludge is mixed with ashes, has been installed in the dewatering plant. The construction costs for the installation of the multiple hearth furnace and centrifuge were approx. 18,5 million DM.
Introduction to the Delta Case Studies
Authors: Knoester M
Published: May 2018

In 1953 a disastrous storm flood stroke the Dutch Delta Region. Since, an extensive program for safe-guarding the area is being carried out. Essential part of the program is to obtain a new primary defence against storm floods by building water barriers between the islands (the Delta Project).

The basins in between, formerly estuarine systems, are each affected in a different way. The matter is presented as a set of three papers, each one dealing with a large basin. Below a common introduction is given, including the motives and how the decision for the Delta Project was made.
The Technical and Economic Aspects of the Water Separation System of the Krammer Locks
Authors: Hillen J G , Ockhuysen C P , Kuur P v.d
Published: May 2018

This paper will deal with some technical and hydraulical aspects of the water separation system of the Krammer Locks in the Netherlands. Attention will be paid to the impact on the environment (salinity of the freshwater lake and of the Eastern Scheldt), to the energy consumption of the pumping station and the consequences for inland water transport. The effect of different ways to operate these locks will be shown.
Response of Macrozoobenthos to a Temporal Lowering of Chlorinity: A Large-Scale Field Experiment in the Dutch Delta Area1
Authors: Coosen J , Leewis R J
Published: May 2018

During the winter 1979/1980 the chlorinity in the Keeten-Krammer-Volkerak-area was considerably lowered, due to an experimental doubling of the freshwater discharge at the Volkerak sluices. To assess the possible impact, species composition, abundance and biomass of the intertidal macrozoobenthos was studied prior to (1978, 1979) and after (1980, 1981) the experiment. In order to prevent damage to the local commercial mussel-stocks, the condition of Mytilusedulis and water-quality-parameters were studied during the experiment. The species that were frequently found before the experiment were still abundant afterwards. Nevertheless, species number directly after the experiment was lower than before. Some of the relatively rare species that were not found immediately after the experiment, were present again later in 1980. The Shannon-Weaver diversity index did not show a significant change. Sample-classification using the Bray-Curtis dissimilarity-index, indicated that most pre-experimental samples were similar to post-experimental samples. Dissimilarity was found between March and October samples. Although locally high values of ammonia and E. colibacteria occurred, the water quality in general remained relatively good. The condition of the mussels was not demonstrably influenced by the experiment. Moreover, young mussels transferred to a control area in the Oosterschelde showed good growth, indicating also a recovery from the exposure to lower chlorinities.
The Nakdong Estuary Barrage and Land Reclamation Project
Authors: Ho Kim Ke , van Houweninge G
Published: May 2018

As a result of the increasing industrial, municipal and agricultural water demand in the Nakdong River Basin, the available amount of fresh river water to repulse salinity intrusion into the lower reaches of the river rapidly decreases during the dry season. Hence the continuity of fresh water supply to the city of Busan, is endangered. The most appropriate solution, both technically and economically is a barrage and enclosure dam in the river estuary. A study was carried out on the interaction between the barrage construction and the estuary and river environment. This study comprised ecological, water quality and morphological aspects. The results were incorporated into the technical design and proposed management of the barrage. This approach resulted in a solution, where the primary objective of the barrage, salinity repulsion, was achieved with a minimised impact on the environment.
Integration of Ecological and Engineering Aspects in Planning Large Scale Tidal Power Development in the Bay of Fundy, Canada
Authors: Gordon Donald C
Published: May 2018

Large-scale tidal power development in the Bay of Fundy has been given serious consideration for over 60 years. There has been a long history of productive interaction between environmental scientists and engineers durinn the many feasibility studies undertaken. Up until recently, tidal power proposals were dropped on economic grounds. However, large-scale development in the upper reaches of the Bay of Fundy now appears to be economically viable and a pre-commitment design program is highly likely in the near future. A large number of basic scientific research studies have been and are being conducted by government and university scientists. Likely environmental impacts have been examined by scientists and engineers together in a preliminary fashion on several occasions. A full environmental assessment will be conducted before a final decision is made and the results will definately influence the outcome.
Environmental Consequences and Ameliorative Measures of the Annapolis Tidal Power Project
Authors: Daborn G R , Baker G C , Dadswell M J
Published: May 2018

A 7.6 m diameter straight flow turbine was installed in an existing rockfill tidal dam at Annapolis Royal, Nova Scotia. Operation as an ebb-flow generator will yield 17.8 MW at heads of 5–6 m. Environmental consequences, and changes in design and operating mode, and remedial measures required to accommodate effects on agriculture and fish passage are outlined. The process of environmental impact assessment and integration is described and discussed.
Environmental Aspects Connected with “High Water” Protection of Venice
Authors: Passino R , Todisco A
Published: May 2018

In this case-study engineering and environmental aspects of the project for “high water” protection of the lagoon of Venice are described.
Environmental Aspects of Reinforcements in Coastal Dune Areas
Authors: de Jong G J , Visser J
Published: May 2018

Dune reinforcements are carried out in dunes, which are not strong enough according to safety standards for the coast-defence. This kind of interventions changes the existing landscape and its functional uses in a less or more extended way. More and more attention is paid to the landscape and ecological aspects in the preparation and the execution of reinforcement projects.

This paper will focus on a reinforcement project, in which engineers, landscape experts and ecologists have worked together. Based on the experience in this project and on a more fundamental theoretical concept conclusions and recommendations are made for this kind of projects.
Sedimentological and Biological Changes Associated with the Construction of the Oil Terminal of Antifer, France
Authors: Monbet Y
Published: May 2018

A study was conducted to gain insight on actual sedimentological and biological effects associated with the construction of an oil Terminal designed to receive 500 000 d.w.t. tankers. Field investigations and subsequent laboratory analyses were organized to evaluate the nature and magnitude of environmental changes on benthic macrofauna, three years after the end of the construction.

Sediments were found to decrease dramatically in medium grain size in area sheltered by the newly built breakwater. Increase of percentage of silt and clays (90 % against 20 %) was observed leeward of the jetty.

The benthic fauna showed significant modifications. Although the same community (Pectinaria kareni Abra alba) recolonized the bottom after the dredging of up to 30 × 106 m3 of sediments, increase in abundance occured. Biomass remained at a constant level and decrease of diversity was observed. Considering the rate of siltation, and assuming a constant siltation rate equal to the rate observed from 1975 to 1978, a simple regressive model relating biomass to mean grain size of sediments has been developped. This model allowed the prediction of biomass and production of the two principal species for the period 1978 – 1981. Continuous siltation within the harbor leads to a maximum of biomass from years after the end of the construction, followed by a decrease of standing stock. This process may be explained by the respective tolerance of the two principal species to increase silt contant and also probably by the accumulation of organic matter which may impede the development of natural populations.
Ecological Control of Engineering Works in the Maracaibo System
Authors: Rodríguez G
Published: May 2018

Lake Maracaibo has one of the largest concentrations of oil production in the world and a large fraction of the production is exported in tankers. The first important change in this system took place when a navigation channel was dredged. A possible salinization of the lake raised considerable concern, but in detailed surveys of the biota no appreciable changes were detected. Afterwards two alternative projects were designed to protect the channel from heavy silting:a terminal dike to close the estuary;lateral dikes along each side of the navigation channel. A long-range study of the interchange of waters and organisms between the various components of the system showed that migratory processes played a considerable role, and it was decided to follow the second engineering alternative. A monitoring program was established to detect any long-term effects on the biota. Up to today no major effects due to the engineering works have been observed. The project provided insight into the interactions between ecologists and engineers in the decision-making process concerning large hydraulic projects in sensitive estuarine areas.
Environmental Impact Assessment of the Strangford Lough Tidal Power Barrage Scheme in Northern Ireland
Authors: Carter R W G , Newbould P J
Published: May 2018

A tidal power barrage on Strangford Lough, would supply about 10% of Northern Ireland's energy requirements in the year 2000. However, the Droject will have serious environmental consequences for the largely unpolluted estuary which contains rare floral and faunal elements, provides a major bird feeding ground and has considerable recreation potential. This article reviews the likely environmental impact of the project.
The Impact and Mitigation of Man-Made Canals in Coastal Louisiana
Authors: Turner R E , McKee K L , Sikora W B , Sikora J P , Mendelssohn I A , Swenson E , Neill C , Leibowitz S G , Pedrazini F
Published: May 2018

Coastal landloss in the sedimentary deltaic plain of southern Louisiana is 0.8% annually and is rising geometrically with time. Landloss is directly correlated with man-made features, particularly canals. The local and indirect effects of canals are modified by the deltaic substrate, distance to the coast, and availability of new sediments. The local impacts are similar to those observed for mosquito ditching along the eastern Atlantic seaboard, even though the canals are typically 10 times larger than mosquito ditches.

Some cumulative impacts of land losses are increased saltwater intrusion, loss of the capacity to buffer the impact of storms and fertilizers and diminished fisheries.

The mechanism for the role of coastal engineering, particularly canal construction, probably involves an alteration in wetland hydrology, but a more complete understanding is presently lacking. Principles for modifying present canal construction projects are presented and include the rationale for: maintaining natural subsurface and overland waterflow patterns, reducing compaction by spoil banks, backfilling canals no longer needed, and the greater use of existing canal corridors in lieu of new canal construction.
Integration of Ecological and Engineering Investigation over Recent Years in England and Wales and the Far East
Authors: Ruxton T D , Downing A L
Published: May 2018

Several feasibility studies requiring ecological and engineering investigations have been carried out recently in England and Wales. The organisation and outcome of investigations for three such studies are described. The ecological and engineering investigations for the Dee Estuary were generally carried out separately whilst those for the Wash were well integrated. In both studies the proposed schemes for development were generally agreed to be those most acceptable on environmental grounds, though many ecologists would prefer that there was no development in either place. Recent investigations for the Severn Estuary have involved ecologists at all levels of planning, study and decision-making though there was less integration than for the Wash studies. Existing ecological models were used in the investigations and future fully integrated studies were planned jointly between engineers and ecologists. The methods used in the Severn have been taken a step further in a fully integrated study in the Far East where engineering and ecological models are being used together to provide a tool for urban planning, management of pollution control and the marine environment.
The Spread of Pollutants from Harbour Sludge Depots
Authors: Loxham M , Weststrate F
Published: May 2018

It is generally agreed that both the landfill option, or the civil techniques option for the final disposal of contaminated harbour sludge involves the isolation of the sludge from the environment. For short time scales, engineered barriers such as a bentonite screen, plastic sheets, pumping strategies etc. can be used. However for long time scales the effectiveness of such measures cannot be counted upon. It is thus necessary to be able to predict the long term environmenttal spread of contaminants from a mature landfill.

A model is presented that considers diffusion and adsorption in the landfill site and convection and adsorption in the underlaying aquifer. From a parameter analysis starting form practical values it is shown that the adsorption behaviour and the molecular diffusion coefficient of the sludge, are the key parameters involved in the near field. The dilution effects of the far field migration patterns are also illustrated.
Environmental Conflicts in a Rapidly Growing Coastal Economy: The Case of South Florida
Authors: Dzurik Andrew A
Published: May 2018

The coastal areas of South Florida contain hundreds of kilometers of beaches, barrier islands, estuaries and coastal wetlands; they also hold most of the state's major centers of population. As South Florida continues to grow rapidly, numerous environmental problems associated with coastal engineering projects must be addressed. The paper discusses selected states legislation and several notable examples of conflicts between development and the coastal environment: construction on coastal wetlands; water supply requirements of rapid growth; nuclear power plant siting; and protection of beaches and barrier islands. It also considers the need to resolve such conflicts and to balance the requirements of coastal engineering projects with environmental protection.
Renewal and Use of the Mississippi River Deltaic Plain
Authors: van Beek J L , Gagliano S M
Published: May 2018

As a result of human intervention in the natural succession of delta complexes, physical and biological integrity of the Mississippi River deltaic plain is reduced to critical levels as indicated by an annual wetland loss of 100 km2. Because of dependence of the socioeconomic system on the given natural setting and diversity, the documented acceleration of environmental change will severely affect economic and social conditions within the next century. Effects include flooding, saltwater intrusion, and loss of wetland-based resources. To abate forthcoming losses, a comprehensive resource protection and management plan must be developed and implemented. Such a plan must utilize to the fullest extent possible the Mississippi River resources of water and sediment through diversion and controlled delta building and must provide for protection of a permanent socioeconomic resource base.
Disposal of Drainage Water from Irrigated Alluvial Plains
Authors: Robson J F , Stoner R F , Perry J H
Published: May 2018

In this paper the problems associated with the drainage of irrigated alluvial plains are discussed with particular reference to the disposal of saline drainage water. The drainage problems within two specific regions are outlined, the Tigris-Euphrates plain in Iraq and the lower Indus plain in Pakistan. For both regions details are given of present and future drainage water disposal methods.
Estimation of Acceptable Water Quality Conditions in the Tama River, Japan
Authors: Ichikawa Arata , Tamai Nobuyuki , Nakayama Yoshio , Amano Kohji
Published: May 2018

In order to describe or reproduce the real water conditions in the river, we propose a method for adjustment of the observed data which we obtained in our river survey. By using these adjusted parameters, the mass-balances of flux and pollutants hold well, so we define it as a “reasonable water condition. And also, these reasonable parameters were used in models based on the Streeter-Phelps equation describing self purification in a river. The results predicted by these model studies were then compared with the actual conditions in the Tama River. In some cases it was possible, and permissible, to make modifications to the model which improved the agreement between the predicted and the observed results; in other cases, this was not permissible. It was concluded that self purification due to biological oxidation is described satisfactorily by the modified model.
Effluent Standards for Reclaiming Industrial Rivers
Authors: Tench H B
Published: May 2018

In industrial areas the waste water from the high concentration of population and heavy industry can cause overload of relatively small rivers. Uniform emission standards for the discharges are inappropriate even in these areas as variations in river flows would make a uniform standard too relaxed or too stringent, according to circumstances, at different points. The problem of fixing river quality standards which would allow fish to repopulate the industrial rivers in Yorkshire and then of applying them to produce appropriate standards for effluents has been examined by a group from the Yorkshire Water Authority. Provisional river water quality standards are recommended in different forms and the bases for these are discussed and comparisons made with the field measurements of river water qualities and the presence of fish. The standards are suggested as mean or median or 95 percentiles as appropriate and also in some cases as maxima which should not recur more often than a critical period if fisheries are to be self sustaining. Methods for applying them to the many effluent discharges in the industrial areas of Yorkshire are also discussed.