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This study aims to investigate the hydraulic behaviour of a pilot-scale, two-staged, vertical flow constructed wetland (VFCW) for septage treatment, in terms of factors such as hydraulic retention time and hydraulic loading rate and its influence on the treatment dynamics. Because of intermittent feeding mode of VFCW systems and variation in its loading, its hydraulic behaviour is highly variable and need to be understood to optimize its treatment performance.

Tracer test were carried out using bromide ion with varying hydraulic loading rates (HLR) of 6.82 cm/d, 9.09 cm/d and 11.40 cm/d (i.e. equivalent to 75 L/d, 100L/d and 125 L/d). Tracer data is then analysed using the Residence Time Distribution (RTD) method.

RTD analysis showed that the increase in HLR increases the average hydraulic retention time (HRT). Subsequently, the increase in HLR results in a lower recovery of effluent, resulting in poor productivity in treatment. The study also showed that the removal of nitrogen and organic matter improved with increasing HRT. However, observations show no correlation between HRT and total solids removal.

A performance evaluation method (by tracer) is proposed to understand the hydraulics of flow in constructed wetlands, which has not been widely studied. Additionally, the dynamics of treatment in VFCWs treating septage may also be revealed by the tracer method. The study can be applied to any constructed wetlands designed for treatment of wastewater, septage or sludge.

Many countries all over the world are facing water shortages. As population increases, water is being perceived as a very valuable resource. Every effort is exerted to use water more efficiently and to make use of every drop of water to ensure the well being of future generations. New trends are developed and practiced in the area of water resources use and water saving. These trends vary from one country to another according to the degree of water scarcity, economic situations, and other factors. Developing non‐conventional water resources is an example of the recent trends in developing new water resources and water savings. Unlike rainfall, rivers, and groundwater which are considered conventional freshwater resources, the non‐conventional water resources include sea water desalination, agriculture wastewater reuse, and municipal wastewater reuse. This paper deals with the reuse of agriculture, municipal, and industrial wastewater as a new trend in developing additional water resources. Special interest is given to municipal wastewater, its characteristics and necessary treatment. Environmental and human health considerations for wastewater reuse, especially in agriculture, are also discussed. Possible consequences of wastewater reuse are introduced. Examples of wastewater reuse practices in some countries are also mentioned.

Increased annual precipitation and more frequent episodes with heavy precipitation are expected in Norway due to climate change. The purpose of this paper is to use two case studies to investigate effects of precipitation on the amounts of faecal indicator bacteria and parasitic protozoa (Cryptosporidium and Giardia) loaded to surface waters from catchment areas exposed to different faecal sources.

In the first case study, the loads of faecal indicator bacteria and Cryptosporidium and Giardia, were investigated in relation to precipitation in a stream from a small valley where cattle and sheep are grazed. In the second case study, historical data (monthly values from 2004‐2009) regarding faecal coliforms and water flow in five tributaries (urban and rural) of a lake used as a drinking water source, were used for calculating loads of faecal indicator bacteria. These loads were evaluated in relation to historical data on precipitation. Additional sampling during/after rainfall, including analysis of samples for Cryptosporidium and Giardia, was performed.

The study visualises how heavy rainfall may increase the load of faecal microorganisms and potential pathogens in Norwegian water sources.

This study provides supplementary information about microbial contamination (including by parasites) of Norwegian surface waters during or after rainfall. This is useful input for decision making regarding protection of vulnerable water sources and for risk assessments. Data are also provided for evaluation of water treatment needs for Norwegian municipalities and waterworks responsible for providing safe drinking water under future climatic conditions.

The purpose of this paper is to assess the water quality parameters resulting on: First, the flow direction in biofilters (ascending or descending), second, constructed wetland (CW) with local plant species and third, the combined system for the removal of organic matter and nutrients pollutants from water in arid regions.

An integrated system is presented and tested in situ with a vertical up-flow and down-flow biofilters. Two configurations schemes are followed by a three separated horizontal subsurface CWs: two planted with Phragmites australis, Typha latifolia and the third unplanted. The methodology is based on a statistical analysis of the collected data.

The present experiment demonstrated that the wetlands planted with P. australis and T. latifolia showed the highest removal. Moreover, T. latifolia performed better than P. australis for most of the parameters, notably in the first system, whereas the wetland efficiency indicated that P. australis contributed greatly to the removal of TP in the first system and NO₃-N in the second system. In general, for the highest removal efficiencies of the combined biofilters and wetlands system, the present study demonstrated that the first system performed better than the second for all the parameters.

The originality of the research is that it compares in situ two biofilter systems: vertical up-flow and down-flow biofilters. To avoid the effects of domestic wastewater that is discharged directly without treatment in the Oued Righ channel or in the lake, this integrated system can be one of the alternatives for wastewater treatment, as it reveals the need to protect aquatic ecosystems in arid regions, and can decrease the risks to human health and the environment.

This paper, which is based on experience from a recent, large, social‐marketing intervention to improve reproductive health in Orissa, India, reviews evidence of harmful effects of improper disposal of male condoms, e.g. ingestion by cattle, effects on humans (e.g. rag pickers), length of time to biodegrade, drain blockage, screen‐cleaning and disposal costs to waste‐water treatment systems. Evidence of impact on the aquatic environment, of hormones from oral contraceptive pills excreted in urine was examined. Given the dearth of published and anecdotal data on the subject, it is concluded that further evidence of the magnitude and severity of the problem in Orissa and similar places in less developed countries is required to facilitate planning of mitigation actions that can be incorporated into social marketing of reversible contraceptives.