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Abstract: Sand filters systems are widely used around the world for on-site and small communities wastewater treatment. Their treatment efficiency depends on several parameters like the media used, temperature, wastewater characteristics, hydraulic and organic loads. One of the most important design parameter in relation to treatment efficiency and sustainability (clogging phenomena) is the sand characteristics and its implementation. To precise the impact of sand implementation on hydraulic and biological behaviors, a study has been done in laboratory columns (surface 0.1m2) in relation to physical and mechanical characteristics of the sand. Two sands (d10 0.42 and 0.8 mm) as well as two implementations (natural compaction and 100% proctor compaction) have been studied during 8 months fed with synthetic wastewater. The weight of the columns was followed continuously and it allowed the following of different parameters (media humidity, infiltration rate, drainage flow). Other parameters linked to biological activity (treatment efficiency (BOD5, COD, SS, nitrogen forms, etc.), oxygen content of the porous gas phase) were followed on a daily basis. The results give information on the importance of media implementation on treatment efficiency and gas and water transfers within the sand filter. Physical parameters, like particle size distribution, are not the only ones to be determinant on biological and hydraulic behaviors of sand filters. If sand compaction can be detrimental in terms of clogging for fine sands, it can be beneficial for coarser sands. This has to be known to avoid bad design and clogging risks. [Copyright &y& Elsevier]

Abstract: Despite all efforts and significant investment in the sanitation sector; sub-Saharan Africa is far behind its Millennium Development Goal (MDG) target. Community led total sanitation (CLTS) is a concept that revisits all the past approaches, particularly the promotion of household sanitation within the context of basic human dignity. CLTS emphasises community facilitation to assess their sanitation situation and promotes natural leaders. CLTS supports community action plans developed under their leadership. The main yardstick of CLTS achievement is totally open defecation free (ODF) villages and not numbers of toilets. This paper reviews Plan’s experiences of promoting CLTS in Eastern and Southern African Countries. The potential of CLTS addressing the issue of scale and long term sustainability within the national planning framework is recognised and lessons learnt from ongoing programs in Ethiopia and Tanzania are shared. The challenges and some limitations of CLTS are critically assessed by this paper and issues needing more research and studies are presented. [Copyright &y& Elsevier]

Abstract: In sub-Saharan Africa 85% of those without access to safe water live in rural areas where the consequent poverty and ill health disproportionately affect women and children. The widespread development of groundwater is the most affordable and sustainable way of improving access to secure water for the rural poor on the scale required to achieve current coverage targets. However, groundwater resources vary considerably across the continent, and the sustainable development of the resource depends on an accurate understanding of the hydrogeology. To develop secure water supplies, the quantity, quality and sustainability of groundwater resources must be known to ensure that key decisions are informed by knowledge of resource conditions. Communities must also be involved at every stage of the process and given the authority to manage and maintain sources. There is a danger that the current pressure to achieve ambitious coverage targets will result in short cuts being taken and, although many new sources are constructed, they will not be secure. [Copyright &y& Elsevier]

Abstract: Lake Victoria basin has a large rural and rapidly growing peri-urban population that lacks sustainable solutions to safe and adequate water supply, energy and sanitation. Access to safe water and sanitation was 60% and 53%, respectively, by 2006. An Integrated Water, Energy and Sanitation Solution (IWESS) has been muted as a sustainable way of utilising the natural resources through a concept that turns waste into a resource thereby taking advantage of what is currently considered as problem sources and converting them into useful inputs. Tests from the Pilot sites developed show that grey and black water, kitchen and solid human waste can be used as separate inputs into an integrated waste management technological chain system that incorporates a constructed wetland-biogas-sand filter system to purify water and biodegrade solid waste to provide water for non-potable uses, biomass and biogas for energy and timber supply and manure for soil nutrient enrichment. [Copyright &y& Elsevier]

Abstract: Africa is not only suffering from water shortage but also from data shortage. The continent cannot fall back on a cross-country hydro-meteorological measuring net. Development cooperation organizations as planners often have the problem that no, or insufficient, hydro-meteorological data is available, even though these are of great importance for sustainable water resources management. Usable water deposits are often not recorded in quantity, quality or in spatial and temporal distribution. The negative effects of insufficient data can only be avoided on a long-term basis. One has to know where, when and how much precipitation, evaporation, runoff and groundwater recharge can be expected. This is the basis for sustainable planning in the field of water resources management, agriculture, hydropower generation, erosion control, etc. The answer is the ‘‘setting up of a cross-national hydrometeorological measuring net for creating the preconditions of sustainable water resources management’’. [Copyright &y& Elsevier]

Abstract: This paper examines some of the challenges related to international development, delivery of the UN Millennium Development Goals and the provision of effective infrastructure, in particular with respect to safe water supplies and sanitation. [Copyright &y& Elsevier]

Abstract: Over one billion people are without access to safe water, while twice as many lack access to improved sanitation services, making these two of the world’s most pressing issues. The sustainability of critical infrastructure systems, such as water and sanitation, is a necessary (though not sufficient) criterion for achieving sustainable human settlements since the lack of adequate services affects literally all aspects of a community’s daily existence including health, education, family, surroundings, and employment. Despite several decades of development aid, infrastructure solutions have not significantly improved these water and sanitation problems (with few exceptions). In this paper, we consider the holistic nature of water infrastructure development in terms of rural areas in developing countries. We propose an outcome-based evaluation method using Life-Cycle Analysis to examine three categories of infrastructure sustainability metrics: technical, environmental, and economic; both froma community perspective, and a social-equity perspective. We demonstrate the method with a simple, generic example of arsenic treatment approaches in Bangladesh. [Copyright &y& Elsevier]

Abstract: An important aspect of urban water systems is the interactions that take place between different components of the system (e.g. foul water from leaky sewers entering into a drinking water distribution network). It is widely recognised that it is important to consider these interactions in order to maintain effective, efficient and safe water and sanitation services. Hence, an integrated approach to urban water management (IUWM) is necessary. This paper begins by presenting a case study in India that highlights the important interactions that takes place between different components of the urban water system. The case study highlights the need to recognise these interactions in order to provide safe and sustainable urban water services. The paper then presents ongoing research on development of integrated urban water modelling tool that allows an integrated approach to urban water services. By applying an IUWMapproach it is possible to satisfy the water and sanitation needs of a community at the lowest cost to society whilst minimising environmental and social impacts. [Copyright &y& Elsevier]

Abstract: The earthquake of 8 October, 2005, severely affected the existing drinking water-supply and sanitation systems in five districts of Pakistan. Wells and springs reported significant reduction in yield with water sources buried under land slides along with considerable damage of sewerage networks, drains, and related infrastructure. In response to the tragedy, the Government of Pakistan, in collaboration with international development partners UNICEF, UNDP, etc., launched a water and sanitation (WS) emergency relief program. The program entailed restoration of water-supply systems, laying of distribution system and provision of storage tanks, using rainwater, distribution of water purification systems, etc. Despite the difficulties, clean water is being provided for several people. In remote mountain areas hill torrent is used through metal pipes that descend in the form of a stream in the mountains. The authors suggest in this paper, micro rooftop rainwater harvesting projects in the affected areas based on the lessons derived from recovery role of similar projects in Banda Aceh in Indonesia. [Copyright &y& Elsevier]

Abstract: In the World Health Organisation (WHO) European Region, 120 million people do not have access to safe drinking water, and even more lack access to hygienic sanitary facilities. Better management of water and sanitation would prevent over 30 million cases of water-related disease per year in the region. Fewdata are collected or known about the access to adequate water supply and safe sanitation for public institutions such as schools. Since the independency in former Soviet states like Ukraine, Moldova, Armenia and others, existing central water and sewage systems are often badly maintained and no longer functioning. Women in Europe for a Common Future (WECF) gained experience on issues of water and sanitation in the rural areas of the new assessed EU countries Romania and Bulgaria and in 10 EECCA countries. WECF observed in the rural areas of those countries the most worse conditions of school sanitation: Groundwater is polluted by infiltration of nitrates and micro organism. Visiting the latrine is a threat to children’s health. The toilets are far away from the school, do not give privacy and are unhygienic. As much as possible, children and school staff try to avoid a visit of the facility by a low intake of liquids. During the period of menstruation girls prefer to stay at home. In demonstration projects, WECF has improved the sanitary condition of the schools and shown how to manage human excreta in an affordable, safe and sustainable way. It was shown, that even without a connection to the central water or sewage system, the dry urine-diverting toilet is a very fast and easy tool to improving the sanitary conditions of schools in an affordable and sustainable way, and to protect groundwater against infiltration of human excreta. School sanitation is an issue that needs the attention of regional, national and international policy makers. In order to improve the sanitary conditions in schools, regulations on the adoption of urine-diversion systems and the reuse of the human excreta in agriculture are needed. [Copyright &y& Elsevier]

Abstract: Recently, wastewater reuse is receiving a great deal of focus and interest among planners and decision makers in the West Bank, Palestine. This interest in wastewater reuse is motivated by the shortage in water resources accessibility due to the unstable political situation in the region. Much of the recent dispute that took place at the national level and among the stakeholders and planners revolved around issues related to the priorities of wastewater reuse in terms of location implementation of reuse schemes. The paper illustrates the conceptual framework for developing such a map and elaborates on the factors that dictate map development. Examples of such factors are discussed. The paper’s outcomes show that the development of the map requires a multi-disciplinary expertise and the work necessitates the collaboration among experts from different fields. [Copyright &y& Elsevier]

Abstract: Municipal authorities in developing countries are facing immense challenges in managing both solid and liquid waste in a sustainable way. Recycling is not yet high on their agenda although they appreciate the potential of composting for waste volume reduction. This offers an entry point to introduce organic waste recycling as a component of sustainable integrated sanitation which has the potential of a win-win situation by reducing waste flows, ensuring environmental health, supporting food production and creating livelihoods. However, due to several constraints recycling attempts have often a short life time. This paper tries to analyse related reasons by drawing from a larger study in Ghana and a survey of compost stations in different parts of Africa. It concludes with a framework for the analysis and the planning of recycling interventions in the context of sustainable sanitation, looking in particular at community-based options for solid waste and human excreta. [Copyright &y& Elsevier]

Abstract: Interesting prospects of a urine-based product exist as a fertilizer in agricultural applications in developing countries. However, removal of pharmaceutical residues is essential to prevent long-termenvironmental hazards. In this paper, the perspectives of urine collection and treatment are discussed with a perspective of the developing countries. Scenarios are drawn up and discussed around the processes of electrodialysis, precipitation and evaporation. A new process combination is presented consisting of nitrification in sand filters and solar evaporation, which could potentially be implemented in developing countries. Such a scenario enables good perspectives for local business development, which is an important prerequisite for the implementation of new technologies in the developing countries. [Copyright &y& Elsevier]

Abstract: Biosorption has emerged as an alternative sustainable strategy for cleaning up water contaminated through industrial activities and/or natural processes. Since biomaterials contain discrete reactive sites to which adsorption takes place, the biosorption process is amenable to thermodynamic treatment using surface complexation theory, enabling the development of predictive models for complex natural or industrial mixtures. In this paper, we present such a surface complexation formalism as it relates to bacterial surfaces, which is verified using proton and single metal biosorption data plotted as a function of pH. The parameters extracted from these verification experiments are then used to predict biosorption in mixtures of metals, with excellent success. The model should be applicable to other biomaterials, such as algae, fungi and higher plants. [Copyright &y& Elsevier]

Abstract: Permeable reactive barriers (PRBs) are a proven technology for remediating contaminated groundwater, particularly on industrial and mining sites. PRBs are a sustainable technology that can operate over a long time scale with low maintenance. Over the past 10–15 years, there have been great strides in refining site characterisation techniques (i.e. geophysical techniques), developing/discovering reactive materials/sorbents (i.e. Fe0 filings), and the installation and design of PRBs (i.e. funnel-and-gate design) which have increased the cost-effeciveness of this technology. Prior to installation, careful consideration of the ease of removal of the PRB should be considered as part of the design. This is important as the PRBmay eventually need to be decommissioned. PRBs are a sustainable site specific remediation technology that has the great potential to work well as a part of a larger scale integrated water resource management programme in developing countries. [Copyright &y& Elsevier]

Abstract: Coverage of adequate sanitation facilities in rural areas in Monkey Bay is low despite initiatives by Non Governmental Organisations (NGOs), government institutions and the local community. NGOs have donated cement, reinforcement bars, and moulds for making 4000 dome slabs. They also trained volunteers to help the communities construct latrines. In addition, they trained local leaders on sanitation and hygiene. The communities provided bricks, sand, quarry stone and labour as a prerequisite to benefit from donations by theNGOs. A follow up survey after the initial intervention revealed that out of 21314 (100%) households, 54.4% had traditional pit latrines of which 4% had dome slabs. Coverage of kitchens, bath shelters and refuse pits was 55%, 67% and 21%, respectively. This paper analyses sanitation initiatives by NGOs and local communities, factors attributing to lowcoverage of sanitation facilities and also sustainability of sanitation interventions in the area. [Copyright &y& Elsevier]

Abstract: Researches aiming at assessing the potentials of vertical-flowconstructed wetlands vegetated with Echinochloa pyramidalis as technically feasible approach for sludge dewatering were conducted at yard-scale experimental plant in Yaounde (Cameroon). The performances of the system and the quality of the by-products generated were assessed for more than 6 months of constant solid loading rates with raw faecal sludge. Results revealed that at loading rate of 100–200 kg TS/m2/yr, the system performed well for solid–liquid separation, with an average dry matter content of biosolids ≥30%and pollutant removal efficiencies higher than 77%, 86%, 90%, 90% and 95% for NH4+, TSS, TS, NTK and COD, respectively. Besides this primary goal, the system could generate 100–150 dry tons/ha/yr of forage plant and biosolids rich in nutrients that could be valorised to sustain the technology if safely managed, since helminth egg concentrations in biosolids remained relatively high (79 eggs/g TS). [Copyright &y& Elsevier]

Abstract: There is a critical lack of sanitation in the West Bank (Palestine).Most domestic sewage is disposed of into unlined cesspits or septic tanks, or directly discharged to the environment without treatment. Water resources in the West Bank are limited, and nearly 70% of the water is used for agricultural irrigation. Reuse of treated (reclaimed) wastewater has great potential to alleviate these problems and improve crop yield, but there are many challenges to implementing wastewater reuse. This paper presents a case study in the West Bank town of Tubas, which currently has no sewage collection system or treatment. This study includes traditional engineering design and will address socio-cultural issues through a detailed survey of public perceptions about reclaimed wastewater and an education plan for the various stakeholders in the town. This approach should lead to a wastewater reuse system that is beneficial to Tubas as well as sustainable. [Copyright &y& Elsevier]

Abstract: In this case study, we investigate the applicability of rainwater harvesting as a sustainable water supply option in Banda Aceh, Indonesia, an area severely hit by the tsunami in 2004. Due to technical and geographical factors, the local residents spend approximately 16% of their incomes on the purchase of water. For this reason, a new, economical, and sustainable way of obtaining water is a most important and urgent concern. A team from Seoul National University recently developed and installed several rainwater harvesting systems in the area in January 2007 and 2008, focusing particularly on increasing public awareness of rainwater harvesting and capacity building in Banda Aceh. This paper discusses the general public perceptions, installation methods, and viability of the system. We found that rainwater harvesting, accompanied by an increase in public awareness and appropriate education, can best serve the needs of the community. [Copyright &y& Elsevier]

Abstract: In coastal areas with a shortage of fresh drinking water, but enough wind, the combination of wind energy and reverse osmosis (RO) may provide a sustainable way to produce drinking water. Especially in remote areas the combination is also cost effective. At the moment there are already systems that use windmills in combination with RO installations. But in these systems the wind energy is first transferred to electricity, electricity is stored and used to drive a high-pressure pump. Our system uses a direct mechanical drive of the RO pump by a windmill and storage of clear water covers periods of low wind speed. No electricity is required and the system can be used in remote areas. A commercial windmill, normally used for irrigation purposes, is connected to the RO-piston pump. The installation has a mechanical dry-run protection, low speed and high-speed limitation. The energy recovery system is not only to recover the energy from the concentrate flow, but also to control the water recovery (10–25%). [Copyright &y& Elsevier]

Abstract: Moreover, there is a growing demand for a simple, low capacity drinking water treatment used by local people in developing countries to reduce mortality caused by water born diseases. To solve this problem a small portable water treatment unit with a production capacity of approximately 500 L/day was developed. The unit can operate without the use of external electricity/pumps/generators in order to operate completely independent. The mobile water treatment unit uses tubular ceramic membranes in combination with an anodic oxidation process, powered by a solar power panel. The membranes are cleaned by simple flushing without the use of chemicals and this enables a sustainable production of safe drinking water on every location in the world without replacing polluted filter cartridges. Laboratory tests with several kinds of surface water and effluent of a wastewater treatment plant (WWTP) showed a very stable production and gave very good results in the removal of sediments, colloidal material, bacteria and viruses. [Copyright &y& Elsevier]

Membrane distillation as a means of seawater desalination using solar energy has the potential to help address the challenges associated with the water-energy nexus and reduce energy consumption. However, the development of an efficient, scalable, stable, and sustainable novel solar membrane distillation (SMD) process remains challenging due to the limited number of membrane preparation procedures and system designs. This work, inspired by solar-driven interfacial evaporation, describes an SMD process employing a hydrophobic trilayer membrane and a two-level SMD structure for effective seawater desalination. A polydimethylsiloxane/carbon nanotube/poly(vinylidene fluoride) (PDMS/CNT/PVDF) membrane, prepared by electrospinning and spraying, exhibited broad light absorption, good photothermal conversion, and localized heating of seawater. The novel two-level SMD structure effectively reused the condensed heat and ensured a greater temperature difference for interfacial evaporation and steam transport, thereby improving fresh water productivity. The greatest productivity (1.43 kg m−2 h−1) and salt rejection (99.9%) were achieved under 1 kW m−2 of solar illumination. This low-energy SMD system using solar energy is suitable for emergency water production and offshore seawater desalination. Unlabelled Image • PDMS/CNT/PVDF membrane with a good photo-thermal conversion ability was prepared. • A novel two-level solar membrane distillation with localized heating was designed. • The superhydrophobic structure reduced fouling and achieved 99.9% salt rejection. • The highest fresh water productivity (1.43 kg m−2 h−1) was achieved under 1 sun. [ABSTRACT FROM AUTHOR]