bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of constructed wetland to protect bathing water quality
Authors: Coombes C. , Collett P. J. 
Published: May 2018

The European Bathing Water Directive imposes strict limits on the bacterial quality of waters used by the public for bathing.
At Thurlestone the site chosen for the sewage treatment works needed to improve bathing water quality is adjacent to a site of special scientific interest (SSSI), into which the treated effluent discharges. The effluent is required to be of a high bacteriological quality to protect the bathing water and high chemical quality to protect the SSSI.
South West Water Services (SWWS) in conjunction with their consultants, WS Atkins, designed and installed a horizontal flow Phragmites australis reed bed to give tertiary treatment to the effluent from a trickling filter plant. The media for the reed bed consists of crushed basalt and limestone chippings to try to maximise the phosphate removal from the effluent. The reed bed has been in operation for two years and produced an effluent of excellent quality soon after it was commissioned. Particular attention has been paid to bacteria removal. Total and faecal coliform removal have averaged two logs. Suspended solids and biochemical oxygen demand have averaged less than 5 mg/l in the effluent, with removals greater than 75%. Ammoniacal nitrogen has averaged less than 2 mg/l. The bathing water into which the effluent eventually discharges has not failed the Directive criteria since the works was commissioned.
Domestic wastewater treatment through constructed wetland in India
Authors: Juwarkar A. S. , Oke B. , Juwarkar A. , Patnaik S. M. 
Published: May 2018

The paper highlights the use of constructed wetlands for the removal of BOD, nitrogen, phosphorus and pathogens from primary treated wastewater. The constructed wetland consists of emergent macrophytesTypha latifolia and Phragmites carca grown in cement pipes having 0.1256 m2 area and 0.8 meter deep filled with 30% soil and 70% sand. The hydraulic loadings were maintained at the rate of 5 cm per day.
The BOD removal in wetlands was observed to be 78-91%. The nitrogen content reduced from 30.8 mgl−1 to 9.5 mgl−1 whereas phosphate in treated wetland effluent was 9.6 mgl−1 as against the mean inflow total phosphate content of 14.9 mgl−1.
The country’s first constructed wetland, of 90m × 30m size, was installed at Sainik School, Bhubaneshwar in the State of Orissa. Two types of macrophytes, viz. Typha latifolia and Phragmites carca, were planted. At present 180-200 m3 wastewater is being treated through wetland. BOD and nitrogen removal were 67-90% and 58-63% respectively.
The constructed wetland treatment was found to be efficient in removal of BOD and N, and economically viable. The system, being easy to operate and low cost, can provide an economical viable solution for wastewater management.
Microbiological features of nitrification-denitrification biological excess phosphorus removal systems in the presence of oNP as an inhibitor
Authors: Topalova Y. , Ribarova I. , Dimkov R. , Arsov R. 
Published: May 2018

The ecolog-microbiological structure of activated sludge in nitrification-denitrification biological excess phosphorus removal (NDBEPR) systems in classic version with real wastewaters and in the presence of inhibitor o-nitrophenol (oNP) has been investigated. The amount of the essential physiological groups microorganisms (aerobic-heterotrophic, nitrifying, denitrifying, phosphorus removing bacteria (Poly P, Poly P denitrifying), nitrophenols-degrading and heterotrophic ammonia releasing bacteria) has been defined in the presence of low and high oNP-concentrations. The dynamics of activated sludge microbial structure has been discussed in effect on treatment efficiency towards different parameters – COD, PO43− elimination, ammonia-oxidation, oNP elimination.
The results show that oNP decreases efficiency of biotreatment from 26% to 80% with the increasing of oNP concentration from 9.35 to 85.44 mg/l. The large flexibility and compensative possibilities of AS structure in NDBEPR systems have been established. The amount of poly P and oNP degrading bacteria is increased at high oNP concentration (85.44 mg/l). These microbial groups play the important buffer role for stabilization of BEPR in the presence of inhibitor, as well as for the biodetoxication of oNP.
A legislative initiative for the protection of Black Sea water from industrial indirect discharges
Authors: Paskalev Atanas , Dimova Galina 
Published: May 2018

The legislative initiative is an attempt for elaboration of a programme for control of the industrial wastewaters before their discharge into the sewerage.
A short review of the existing Bulgarian legislation related to the ecological problems of the Black Sea is presented. The main problems obstructing the practical implementation of the laws and the regulations are analysed.
In outlining the approach for control of the industrial discharges, special attention is paid to the necessity of theoretically sound and economically substantiated limits on the discharged wastewaters, extension of the regional authorities' activities on pollution control and involving the municipal Waste Water Treatment Plants (WWTPs) in the wastewater treatment management.
The paper gives directions for the future development of a Black Sea Environmental policy, related to industrial indirect discharges at international, state and regional levels.
The role of non-point nutrient sources in water pollution - present situation, countermeasures, outlook
Authors: Werner W. , Wodsak H.-P. 
Published: May 2018

In a recent estimation of the quantitative importance of diffuse and point sources on the nitrogen and phosphorus pollution of surface waters in both parts of Germany just before the reunification, the share of the diffuse sources on the total input was found very similar in the case of N (56 and 57%), but different in the case of P (42% in the old FRG and 33% in the former GDR). The diffuse N and P inputs are dominated by the joint pathways ground water/drain water and soil erosion/surface run off, respectively. The reduction of the diffuse pollution potential until 1995 (compared to 1987/89) is estimated with about 18% for N and 30% for P. This is far below the governmental target of a 50% reduction in the period 1985 to 1995.
The reasons, why the up-to-now success of the different countermeasures against diffuse water pollution with N and P from agriculture is still unsatisfactory are discussed. Demands for an accelerated implementation of efficient countermeasures have to be addressed by both farmers and politicians.
Artificial mixing: a therapy measure combating cyanobacteria in Lake Nieuwe Meer
Authors: van der Veer Bart , Koedood Jan , Visser Petra M. 
Published: May 2018

In Lake Nieuwe Meer near Amsterdam, the bloomforming cyanobacterium Microcystis aeruginosa dominates the phytoplankton in late summer and forms scums that can be a big nuisance. In Lake Nieuwe Meer the water column is stratified in summer. Microcystis can stay in the euphotic zone due to its buoyancy. Deep mixing of the lake abolishes this advantage of buoyancy of Microcystis and favours non-buoyant algae as they will have a reduced sedimentation loss.
The technique of artificial mixing has been applied in 1993 and 1994 applied in Lake Nieuwe Meer in order to reduce the growth of Microcystis. The application was successful: there has been no nuisance due to Microcystis scums. The percentage cyanobacteria of the total phytoplankton in summer decreased from ±90% without mixing to less than 5% with mixing. Characteristics of the equipment used for destratification are presented.
Clustering of towns and villages for centralized wastewater treatment
Authors: Abd El Gawad Hassaan A. , Butter J. H. C. 
Published: May 2018

In 1993 the Governorate of Fayoum completed its master plan for wastewater management. The master plan presents a staged implementation schedule for the development of wastewater facilities for the Governorate, covering needs up to the year 2020. The targets are ambitious: in order to meet sanitary health standards, nearly two million people (or 60% of the total population) living in 70 towns and villages would need to be served with sewerage systems. Providing all these areas with separate wastewater treatment plants would be impractical. The centralization of treatment at a limited number of treatment plants for clusters of towns and villages has advantages in terms of manageability, cost and environmental protection.
In the master plan the configuration of these clusters is presented. For that purpose a stepped approach has been developed: an approach in which aspects such as construction and operation costs of the facilities, existing infrastructure, the geography of the governorate, environmental impact, alternative treatment technologies and phasing of implementation have been considered. An important element of the stepped approach is an analytical model with which - from financial point of view - the optimum size of a cluster can be estimated. Variables of the model are sizes of towns and villages, distances and treatment technologies. The output of the model is a set of general design criteria which has been applied to the specific situation in the governorate.
The model has contributed to the establishment of the Master Plan for Wastewater: a plan now used by the Fayoum Sanitation Department as a framework to initiate new projects and to direct the activities of other agencies working in the sanitation sector in the governorate.
Impact of improved sewerage systems on groundwater heads in Eastern Cairo region
Authors: Hassan M. M. , El Shiwi M. , Smidt E. 
Published: May 2018

Large areas in Cairo have been experiencing groundwater and water table rise during the last decade. This has resulted in serious problems to the foundations of old houses, antiquities, and monuments. The main causes behind this rising water table and groundwater is the increased recharge from surface activities in a city experiencing increased population. Major sources of recharge in the urban area included leakage from water supply and sewerage pipes, while in the rural areas the major causes included domestic seepage from septic tanks and deep percolation of excess irrigation water in agricultural areas.
Various studies have been conducted to investigate the possible remedial solutions. The most recent study conducted by the Research Institute for Groundwater indicated that the most effective remedial measure is through the reduction of recharge. This was determined through simulation of various remedial measures.
In this paper, a preliminary assessment of the recently improved sewerage system is made. Results indicate considerable reduction in water table levels and groundwater heads in the region. Final assessment would require a thorough investigation of possible other changes in the environment including both quantitative and qualitative aspects.
Consideration of DAF retrofit to a large conventional water treatment plant
Authors: Vallance B. C. , Pritchard R. G. , Hargesheimer E. E. , Seidner R. T. 
Published: May 2018

Recent historical trends have shown a deterioration of raw water quality feeding the 60 year old Glenmore WTP. This deterioration has manifested itself in a chronic increase in nutrient loads and consequent chlorine demand. The plant's existing pre-treatment and sedimentation facilities have had difficulty in handling flash turbidity spikes. Lack of contact time for post chlorination has created a reliance on high pre-chlorination practice to ensure a safe distribution system disinfectant residual. These trends, together with the regulatory authority's tightening of compliance standards and enforcement policies, plus growing public expectations for consistently high quality drinking water, pointed towards a need for a comprehensive assessment of the plant.
The City of Calgary, with its Engineering Consultant, embarked on a programme to review the existing plant facilities; identify alternatives with potential for addressing known concerns; and pilot both conventional and advanced treatment processes side by side, to establish relative and definitive performance data.
This paper addresses the piloting aspect of the study programme, and in particular, the rationale for piloting dissolved air flotation (DAF). Conceptual development, design and construction of the pilot plant are all discussed. The conceptual development was based on the needs and design constraints imposed by the existing plant, such as hydraulic profile. The approach to design was predicated by a desire for a pilot plant that would provide not only guidance for the plant upgrade, but also a working tool for future studies, process monitoring and optimization. The construction and commissioning was planned with a view to having the pilot plant operational in time for spring run-off.
Some of the operational experiences with the pilot plant are discussed. These included modifications to the DAF baffle weir; the collection, display, manipulation and graphing of data from online monitors; filter performance following DAF pre-treatment, and the establishment of a successful set of operating conditions.
The first DAF water treatment plant in the United States
Authors: Nickols David , Moerschell Gerard C. , Broder Michael V. 
Published: May 2018

The Millwood Water Treatment Plant in Westchester County, about 60 kilometres (35 miles) north of New York City, was commissioned in August 1993. This plant is the first dissolved air flotation (DAF) plant in the United States which uses the DAF technology and concepts that have become the industry standards in Europe and Australia. The $19-million plant was built to treat a previously unfiltered supply, to meet the requirements of the new federal Surface Water Treatment Rule.
This paper describes the project in its entirety: starting from the planning, pilot testing, and process selection; proceeding to the means of overcoming resistance to a “new” process and obtaining regulatory body approvals; and outlining the design, process criteria, construction, and start-up of the plant. Operating results are also presented. The plant treats soft, slightly colored, generally low turbidity water which experiences occasional turbidity spikes of 100 NTU or more. The treatment process comprises two-stage mixing, three-stage flocculation, dissolved air flotation, ozonation for primary disinfection, dual-media filtration, and post-treatment with chlorine, sodium hydroxide, orthophosphate and fluoride. Flotation sludge is dewatered in on-site freeze/thaw lagoons for off-site disposal in a landfill.
Effect of advanced oxidation processes on inactivation of coliphages
Authors: Rajala-Mustonen Ritva L. , Heinonen-Tanski Helvi 
Published: May 2018

Chlorine and its derivatives are no longer regarded as acceptable disinfectants of water because of compounds they form with organic material in water. These compounds have been proved to be mutagenic and carcinogenic to man. Alternative disinfectants like UV radiation and ozonization are regarded as less harmful disinfectants of microorganisms in water.
In the present study the effect of UV radiation alone and together with hydrogen peroxide, and ozone treatment on the inactivation of coliphages in tap water were studied. Two phage types, DNA- and RNA-phages were seeded into tap water and exposed to these disinfectants in batch experiments. The inactivation of phages was determined as a reduction of phage titer as a function of contact time.
Disinfection with ozone proved to inactivate coliphages more rapidly than UV light or UV light together with hydrogen peroxide (H2O2). After two minutes exposure time the reduction in phage titer was from 6 to 8 log units with ozone while with UV light or UV with H2O2 the reduction was from three to four log units.
According to these results ozonization seemed to be more efficient disinfectant than UV light radiation.
Managing rivers for conservation and ecotourism in the Kruger National Park
Authors: Venter F. J. , Deacon A. R. 
Published: May 2018

Six major rivers flow through the Kruger National Park (KNP). All these rivers originate outside and to the west of the KNP and are highly utilized. They are crucially important for the conservation of the unique natural environments of the KNP.
The human population growth in the Lowveld during the past two decades brought with it the rapid expansion of irrigation farming, exotic afforestation and land grazed by domestic stock, as well as the establishment of large towns, mines, dams and industries. Along with these developments came overgrazing, erosion, over-utilization and pollution of rivers, as well as clearing of indigenous forests from large areas outside the borders of the KNP.
Over-utilization of the rivers which ultimately flow through the KNP poses one of the most serious challenges to the KNP's management. This paper gives the background to the development in the catchments and highlights the problems which these have caused for the KNP. Management actions which have been taken as well as their results are discussed and solutions to certain problems proposed. Three rivers, namely the Letaba, Olifants and Sabie are respectively described as examples of an over-utilized river, a polluted river and a river which is still in a fairly good condition.
Towards a Water Management Strategy for an environmentally sensitive and popular tourist region
Authors: Kapp J. F. , Fijen A. P. M. , van Zyl F. 
Published: May 2018

This paper describes the development and implementation of an Integrated Water Management Strategy for the catchment of the Wilderness Lakes in the Southern Cape, South Africa. The area is a popular tourist destination due to its environmental variety and scenic beauty.
The main land uses in the catchment are: agriculture, forestry, tourism, residential settlement and the natural environment. These land uses compete for a share of the available water resources and have different water quality demands, while at the same time each has an impact on the water quality and quantity and also on other land uses. The water management strategy developed for Wilderness aimed at the responsible management and fair distribution of the available water resources (both quantity and quality) and on the sustainable use of these resources, taking full cognisance of the wishes and opinions of all interest groups in the area. The natural environment played a very important role in the development of the strategy and it was found that a more natural management of the estuary mouth would assist in maintaining the natural characteristics of the Wilderness system. The paper also addresses the structures and management body proposed to implement the Water Management Strategy.
Development of regional coastal water quality standards in the Mediterranean
Authors: Saliba L. J. 
Published: May 2018

Under the terms of the 1976 Convention for the protection of the Mediterranean Sea against pollution, and the 1980 Protocol for the protection of the Mediterranean Sea against pollution from land-based sources, the coastal states of the region have to develop criteria and standards for various aspects of coastal water quality. These are being progressively developed within the framework of the Mediterranean Action Plan, specifically within the Long-term Programme of Pollution Monitoring and Research in the Mediterranean Sea (MED POL Phase II).
The impact of specific Mediterranean ecological conditions on health and related risks arising from specific uses of the sea, in relation to those risks arising from the same types of water use in regions with different conditions, and the effects of such differences on quality requirements, are discussed.
The current situation in the Mediterranean region regarding national and international legislation for ensuring coastal water quality is described, together with the normal procedures for regional assessments of the situation with regard to specific pollutants and the formulation of proposed measures.
The legal and technical problems involved in (a) the actual preparation of criteria and standards combining ecological and health requirements with political acceptability and (b) their adoption by Mediterranean states are described. These problems essentially arise out of the heterogeneous character of the states bordering the Mediterranean Sea, especially regarding the state of existing infrastructures for pollution prevention and control, including the availability of trained manpower and technical facilities, the degreee of priority accorded to marine pollution within the overall framework of national requirements, the type of legal and administrative machinery for the enactment and enforcement of statutory provisions, and the implications of new or amended legislation vis-a-vis already-existing international obligations.
Chemical pollution from urban and industrial sewages in Augusta Bay (Sicily)
Authors: Magazzù G. , Romeo G. , Azzaro F. , Decembrini F. , Oliva F. , Piperno A. 
Published: May 2018

The Augusta Bay is a complex area where heavy industrialization and dense urbanization have promoted a very high state of degradation. This basin has already been studied for several years because of various eutrophication phenomena which induced a massive fish mortality.
In order to deepen our knowledge on the state of chemical pollution due to Dissolved/Dispersed Petroleum Hydrocarbons (DDPH), detergents and N- and P-salts as well as on the eutrophication of the bay, three campaigns have been carried out. The results (from 0.0 to 96.6 μg/l in chrysene equivalents) have indicated that the distribution of DDPH is characterized by an extreme spatial and temporal variability linked to occasional localized spills and to the wind's action which influences the surface water circulation in the bay.
The concentration of non ionic (BiAS) and ionic (ABS) detergents averages respectively 63 and 55 μg/l with a predominance of BiAS in the waters affected by the urban discharges, while high ABS values have been also measured in correspondence of a cooling water effluent.
Finally, the PO4 (max 0.3 μ/l) and NO2 + NO3 (max 4 μl) levels were relatively low and constant in comparison with previous results, while NH4 remains at a high level (max 14.6 μ/l) with supplies located in the urban discharge as well as in the industrial ones, indicating that both types of effluents are equally responsible for eutrophication and the distrophic crisis observed in the bay.
Description and test of a new generation of nutrient sensors
Authors: Lynggaard-Jensen A. , Eisum N. H. , Rasmussen I. , Svankjær Jacobsen H. , Stenstrøm T. 
Published: May 2018

Sensor prototypes for measurement of ammonium, nitrate and phosphate in wastewater treatment plants are described together with the results obtained in laboratory and pilot scale wastewater treatment plants.
A functional description of the sensor principles is presented together with the installation and operation procedures. Basically the measurements are done using membrane technology in combination with semi-micro Continuous Flow Analysis (μCFA) with classic colorimetry. Because of this the sensors can be installed directly in the aeration tanks without any need for sampling, filtration, etc. Furthermore, the semi-micro scale is used in such a way, that handling of chemicals and waste is a closed loop in a package to be changed once a month.
The sensors have been tested thoroughly in a pilot scale waste water treatment plant (recirculation) using real raw wastewater as well as artificial wastewater. The sensors have been placed directly in the aeration tank or in the anoxic tank of the pilot plant. The tests show very little, if any, fouling problems due to the membrane material used. The test results show a good reproducibility and most important, compared to other available sensors/analyzers on the market, very low response times, less than 5 minutes. Owing to these low response times, experiments with direct measurement of nitrification and denitrification rates were carried out.