Related Publications

Safely managed waste reuse may be a sustainable way to protect human health and livelihoods in agrarian-based countries without adequate sewerage. The safe recovery and reuse of fecal sludge-derived fertilizer (FSF) has become an important policy discussion in low-income economies as a way to manage urban sanitation to benefit peri-urban agriculture. But what drives the user acceptance of composted fecal sludge? We develop a preference-ranking model to understand the attributes of FSF that contribute to its acceptance in Karnataka, India. We use this traditionally economic modeling method to uncover cultural practices and power disparities underlying the waste economy. We model farmowners and farmworkers separately, as the choice to use FSF as an employer versus as an employee is fundamentally different. We find that farmers who are willing to use FSF prefer to conceal its origins from their workers and from their own caste group. This is particularly the case for caste-adhering, vegetarian farmowners. We find that workers are open to using FSF if its attributes resemble cow manure, which they are comfortable handling. The waste economy in rural India remains shaped by caste hierarchies and practices, but these remain unacknowledged in policies promoting sustainable ‘business’ models for safe reuse. Current efforts under consideration toward formalizing the reuse sector should explicitly acknowledge caste practices in the waste economy, or they may perpetuate the size and scope of the caste-based informal sector.

Recycling of wastewater provides a substantial solution to the global issue of water scarcity and high water use in aquaculture. However, this sustainable way of wastewater use has not been given much attention and exploration. This study focused on the consumer preference for fish grown in treated wastewater as well as the effect of aeration on the growth performance and economic benefit of African catfish (Clarias gariepinus) grown in treated wastewater. Two hundred (200) respondents from two communities (Chirapatre and Gyinyase) near the wastewater treatment plant in Kumasi were interviewed to determine their willingness to accept and pay for African catfish grown in treated wastewater. For the growth trial, a total of 600 fish (of average initial weight 39.12g) were stocked in two maturation ponds with 4 h (3:00am7:00am) of aeration daily. The trial lasted for 12 weeks and variables monitored included the survival, growth performance (weight gain, specific growth rate, and yield) and water quality. Fish cultured in non-aerated wastewater ponds (NWFPs) under similar conditions as in aerated wastewater-fed ponds (AWFPs) served as control. The results indicated most important considerations for consumers in their choice of fish to consume were in order of importance; food safety, freshness of fish, taste and packaging. The proximity of consumers to the treatment plant, the price of fish, religion, and age and whether or not they were fish consumers affected their willingness to pay for African catfish grown in the treated wastewater significantly. For the growth trial, dissolved oxygen concentrations in the aerated ponds were significantly higher than in the NWFPs and this led to more than a doubling of the growth rates in the African catfish grown in the AWFPs (189.10g 11.32) as compared to the NWFPs (90.70g 11.59). The pond aeration improved fish growth significantly (p lt; 0.0098). On economic benefit, the aerated system yielded profits of 618.83 (103.13) as compared to a loss of 104.99 (17.50), which was incurred in the non-aerated ponds. Education of the consumers on the process of wastewater treatment and establishment of food safety guidelines will therefore be recommended to increase consumer interest in consuming fish from the treated wastewater.

In 2019, Sri Lanka introduced two policies that referred to food waste and the need to reduce it. To understand key stakeholders’ readiness in this context, this study analyzed the food waste perceptions of private and public sectors in Colombo (open markets, supermarkets, hotels, restaurants, canteens, food caterers and key authorities). Interviews were carried out with operational managers and public officials, as well as other stakeholders who have roles in food waste redistribution and reuse, such as NGOs and the livestock sector. So far, the food-waste-related policy recommendations lack an operational inter-institutional home which can build on measures, like standards, regulations and incentives. Thus, most food waste reduction initiatives are initiated by NGOs or by the private sector, e.g., by larger hotels and supermarket chains. These entities were ready to lead by example, based on the understanding that urban food waste is an internal (financial) management challenge. Among smaller local entities, food waste was perceived more as an external issue to be handled by the city’s waste collection services. Although perceptions varied between entities generating smaller or larger quantities of food waste, there was general agreement that suboptimal capacities and mechanisms to quantify, monitor and cost food waste generation appeared to be obstacles for in-depth awareness creation and action. There was significant interest in communication platforms for cross-sectoral learning, win/win collaborations with reliable collection (reuse) services that are currently operational, such as those provided by piggeries, as well as surplus redistribution initiatives if food safety and related liabilities can be addressed effectively.

Arid areas in East Africa are characterized by physical water scarcity. The physical water scarcity is further exacerbated by poor water quality (mainly salinity and fluoride) of mainly groundwater sources. Combined physical water scarcity and poor water quality makes the region a hydrogeologically difficult environment. Nevertheless, some viable high-yielding aquifers exist in East Africa. Difficult hydrogeology means that the best practices of reaching rural dwellers, towns, and urban centers require specialized financial, technical, and engineering approaches. The chapter describes the hydrogeology difficulty and the ongoing management strategies and its implications for the Water, Sanitation and Hygiene sector in East Africa arid regions.

Large cities in developing countries are facing the challenge of rapid urban population growth, which results in increasing waste generation. In Nairobi, the solid waste situation is characterized by low coverage of collection, pollution from uncontrolled dumping, inefficient public services, unregulated and uncoordinated private sector operators and lack of key solid waste management infrastructure. About 3,121 tons of municipal solid waste (MSW) is generated daily, of which about 850 tons are collected and the remaining is burnt or dumped in unauthorized sites or landfilled in the Dandora dumpsite causing health and environmental problems. The recovery of nutrients from the organic content of MSW for reuse in agriculture has the potential to address the dual challenge of waste management and soil nutrient depletion. This study assessed the economic and environmental impact of decentralized composting business model in Nairobi based on a comparison with the baseline scenario using an indicator expressed in tons CO2 equivalent. The costbenefit analysis was based on data collected from existing compost plants in Kenya. To assess the sensitivity of the results to variation in input variables, a simulation model was developed using the Monte Carlo method. The decentralized composting business model resulted in a net GHG emission saving of 1.21 tons CO2-eq/ton of compost, being both financially and economically feasible with more than 70% chance of economic success. Assessing the economic and environmental impact is an important tool for decision making and to ensure that the business model results in desired benefits to society.

Globally, 50% of the population relies on on-site sanitation systems (OSS) such as septic tanks and pit latrines and is, hence, in need of Fecal Sludge Management (FSM) solutions. India is a classic example, given that its government built more than 100 million toilets with the majority relying on OSS. With 400 fecal sludge treatment plants (FSTPs) in various stages of planning, procurement and construction, this report comes at an opportune time to present findings on FSM business models already implemented across India. Interviews were conducted with a total of 105 Emptying and Transport (Eamp;T) operators in 72 towns and cities across 16 states in India, 22 representatives from municipalities that own emptying vehicles, 18 FSTP operators and more than 30 institutions. In addition, procurement tenders for Eamp;T and FSTPs in 13 states were analyzed. In total, 18 business models were identified, several with energy or nutrient recovery components. The analysis of Eamp;T operators revealed clear differences that steer a business towards success or failure. The majority of operators still dispose fecal sludge in an unsafe manner, due to the lack of official disposal or treatment sites. In comparison to sewer networks, the capital and operating costs (per capita) of FSTPs were significantly lower. The report provides evidence-based discussions on policies and recommendations for scaling and sustaining FSM.

Based on primary data from fecal sludge (FS) treatment plants in three West African urban regions (Ouagadougou in Burkina Faso, Greater Accra in Ghana, and Grand Nokou in Benin), FS collection and treatment patterns were analyzed to identify possible scenarios for resource recovery (RR) through FS co-composting. FS collection was analyzed for up to 7 years, in part per day, month and season, as well as FS characteristics to understand peak flows, FS qualities and related variations to plan for appropriate RR technology and capacities. Overall, the FS volumes collected by vacuum trucks were not significantly affected by the calendar days, months or seasons. Commonly assumed increases during rainy months were, for example, only recorded in Ouagadougou. FS composition appeared highly variable with a pronounced difference in total solids between FS collected from households versus institutional sources, likely indicating that institutions are served more frequently. The analyzed treatment plants appear to be exploited beyond their capacity. RR for reuse can turn sludge disposal from a cost into a source of revenue with co-benefits for farmers and the environment, thereby reducing the pressure on tipping fees. The probability of the added co-compost production being financially viable on its own was estimated for all the study sites, indicating an earliest breakeven point after 5 to 8 years.

Over the last decade, the International Water Management Institute (IWMI) has explored the use of fecal sludge (FS) in combination with other organic waste sources to optimize FS treatment and composting for the production of a safe organic fertilizer, which can depending on demand be enriched with crop nutrients or pelletized for volume reduction, delayed decomposition or easier application. Based on IWMI’s experience, this training manual has been compiled for plant managers and trainers to help ensure that staff involved in FS treatment and production, and application of an FS-based co-compost adopt best practices in all processes involved. The manual can be adapted to local needs as required. It also includes information on compost registration and certification, as well as guidelines for co-compost application in the field.

This chapter addresses the current state of water and climate finance, the costs of inaction versus the benefits of action, and several ways to access climate finance flows to improve water management as well as water supply and sanitation services, while synergistically mitigating and/or adapting to climate change.

This chapter focuses on the human health impacts associated with changes in water quality and quantity due to climate change. Trends in morbidity and mortality are examined in the context of health risks associated with climate change, and response options related to water supply and sanitation are presented.

This chapter establishes linkages between climate change and various aspects of water management. Adaptation and resilience-building options are presented with respect to water storage including groundwater and water supply and sanitation infrastructure, and unconventional water supply options are described. Mitigation options for water management systems are also presented.

As we rapidly modify the environment around us, researchers have a critical role to play in raising our understanding of the interactions between people and the world in which they live. Knowledge and understanding of these interactions are essential for evidence based decision-making on resource use and risk management. In this paper, we explore three research case studies that illustrate co-evolution between people and water systems. In each case study, we highlight how different knowledge and understanding, stemming from different disciplines, can be integrated by complementing narratives with a quantitative modelling approach. We identify several important research practices that must be taken into account when modelling people-water systems: transparency, grounding the model in sound theory, supporting it with the most robust data possible, communicating uncertainty, recognising that there is no ‘one true model’ and diversity in the modelling team. To support interdisciplinary research endeavours, we propose a three-point plan: (1) demonstrating and emphasising that interdisciplinary collaboration can both address existing research questions and identify new, previously unknown questions at the interface between the disciplines; (2) supporting individual interdisciplinary learning at all career stages and (3) developing group practices and a culture of interdisciplinary collaboration.

We describe the technical feasibility of metagenomic water quality analysis using only portable equipment, for example mini-vacuum pumps and filtration units, mini-centrifuges, mini-PCR machines and the memory-stick sized MinION of Oxford Nanopore Technologies, for the library preparation and sequencing of 16S rRNA gene amplicons. Using this portable toolbox on site, we successfully characterized the microbiome of water samples collected from Birtley Sewage Treatment Plant, UK, and its environs. We also demonstrated the applicability of the portable metagenomics toolbox in a low-income country by surveying water samples from the Akaki River around Addis Ababa, Ethiopia. The 16S rRNA gene sequencing workflow, including DNA extraction, PCR amplification, sequencing library preparation, and sequencing was accomplished within one working day. The metagenomic data became available within 24e72 h, depending on internet speed. Metagenomic analysis clearly distinguished the microbiome of pristine samples from sewage influenced water samples. Metagenomic analysis identified the potential role of two bacterial genera not conventionally monitored, Arcobacter and Aeromonas, as predominant faecal pollution indicators/waterborne hazards. Subsequent quantitative PCR analysis validated the high Arcobacter butzleri abundances observed in the urban influenced Akaki River water samples by portable next generation sequencing with the MinION device. Overall, our field deployable metagenomics toolbox advances the capability of scientists to comprehensively monitor microbiomes anywhere in the world, including in the water, food and drinks industries, the health services, agriculture and beyond.

Peri-urban areas are characterized by multifunctional land-use patterns forming a mosaic of built-up and agricultural areas. They are critical for providing food and other agricultural products, livelihood opportunities and multiple ecosystem services, which makes them transformative where urban and rural spaces blend. We analyzed land use changes in a peri-urban micro-watershed in Southern India by using Google Earth data to understand the micro-level spatio-temporal dynamics. This study aims at understanding the peri-urban agriculture and landscape changes as related to the change in use of wastewater and groundwater for irrigation. The temporal dynamics of peri-urban system including the changes in built-up, paragrass, paddy rice and vegetable cultivation, groundwater and wastewater irrigated areas in the watershed were evaluated. The detected changes indicate that, as a consequence of urban pressures, agricultural landscapes are being converted into built-up areas and, at the same time, former barren land is converted to agricultural plots. The mapped land use data are used in landscape change modelling for predicting the peri-urban agricultural dynamics and the driving factors in the watershed. Combined with the mapping and modelling approaches for land use change analysis, our results form the basis for integrated resources management in the wastewater influenced peri-urban systems.

Climatic variability and change result in unreliable and uncertain water availability and contribute to water insecurity in Africa, particularly in arid and semi-arid areas and where water storage infrastructure is limited. Managed aquifer recharge (MAR), which comprises purposeful recharge and storage of surface runoff and treated wastewater in aquifers, serves various purposes, of which a prominent one is to provide a means to mitigate adverse impact of climate variability. Despite clear scope for this technology in Africa, the prevalence and range of MAR experiences in Africa have not been extensively examined. The objective of this article is provide an overview of MAR progress in Africa and to inform the potential for future use of this approach in the continent. Information on MAR from 52 cases in Africa listed in the Global MAR Portal and collated from relevant literature was analyzed. Cases were classified according to 13 key characteristics including objective of the MAR project, technology applied, biophysical conditions, and technical and management challenges. Results of the review indicate that: (i) the extent of MAR practice in Africa is relatively limited, (ii) the main objective of MAR in Africa is to secure and augment water supply and balance variability in supply and demand, (iii) the surface spreading/infiltration method is the most common MAR method, (iv) surface water is the main water source for MAR, and (v) the total annual recharge volume is about 158 Mm3 /year. MAR schemes exist in both urban and rural Africa, which exemplify the advancement of MAR implementation as well as its out scaling potential. Further, MAR schemes are most commonly found in areas of high inter-annual variability in water availability. If properly planned, implemented, managed, maintained and adapted to local conditions, MAR has large potential in securing water and increasing resilience in Africa. Ultimately, realizing the full potential of MAR in Africa will require undertaking hydrogeological and hydrological studies to determine feasibility of MAR, especially in geographic regions of high inter-annual climate variability and growing water demand. This, supported by increased research to gauge success of existing MAR projects and to address challenges, would help with future siting, design and implementation of MAR in Africa.

This article reviews the negative impact of anthropogenic changes on groundwater. The main changes in physical and geographical conditions that occur under the impact of anthropogenic pressures and that have the most significant influence on the state of groundwater, as well as a negative impaction the conditions of the formation of groundwater are: changes in the landscape caused by agricultural works, mining, construction of settlements, etc.; changes in the hydrographic network caused the construction of hydroelectric power facilities; changes in the composition of the atmospheric air; changes in the groundwater level regime, climatic conditions. The most significant factor of change in groundwater formation conditions is the progressive anthropogenic pollution of groundwater. It negatively influences the number of resources and their quality.

Water security is a key in achieving sustainable development goals (SDGs); however, it is gradually becoming a scarce resource due to pressure from both climatic and non-climatic factors. Understanding sources and extend of vulnerability of the water resources is the very frst step to design appropriate strategies aimed at securing water for various uses. This study therefore assessed vulnerability of water resources and its spatial distribution across the Palikas (new local governments) with Gulmi district in Province-5 as the case study. Vulnerability was assessed using an indicator-based framework comprising of two components and six sub-indices. Results showed that Musikot is the highly vulnerable Palika among the 12 Palikas, and Resunga is the least vulnerable. The results are useful for prioritizing the Palikas for allocating resources aimed at targeting new programs for reducing poverty and conserving natural resources.

Urbanisation will be one of the 21st centuryapos;s most transformative trends. By 2050, it will increase from 55% to 68%, more than doubling the urban population in South Asia and Sub-Saharan Africa. Urbanisation has multifarious (positive as well as negative) impacts on the wellbeing of humans and the environment. The 17 UN Sustainable Development Goals (SDGs) form the blueprint to achieve a sustainable future for all. Clean Water and Sanitation is a specific goal (SDG 6) within the suite of 17 interconnected goals. Here we provide an overview of some of the challenges that urbanisation poses in relation to SDG 6, especially in developing economies. Worldwide, several cities are on the verge of water crisis. Water distribution to informal settlements or slums in megacities (e.g. N50% population in the megacities of India) is essentially non-existent and limits access to adequate safe water supply. Besides due to poor sewer connectivity in the emerging economies, there is a heavy reliance on septic tanks, and other on-site sanitation (OSS) system and by 2030, 4.9 billion people are expected to rely on OSS. About 6293% of the urban population in Vietnam, Sri Lanka, the Philippines and Indonesia rely on septic tanks, where septage treatment is rare. Globally, over 80% of wastewater is released to the environment without adequate treatment. About 11% of all irrigated croplands is irrigated with such untreated or poorly treated wastewater. In addition to acute and chronic health effects, this also results in significant pollution of often-limited surface and groundwater resources in Sub-Saharan Africa and Asia. Direct and indirect water reuse plays a key role in global water and food security. Here we offer several suggestions to mitigate water and food insecurity in emerging economies.

The world is not on track to achieve Sustainable Development Goal 6 on clean water and sanitation by 2030. We urge a rapid change of the economics, engineering and management frameworks that guided water policy and investments in the past in order to address the water challenges of our time.

Monitoring the qualitative status of freshwaters is an important goal of the international community, as stated in the Sustainable Development Goal (SDGs) indicator 6.3.2 on good ambient water quality. Monitoring data are, however, lacking in many countries, allegedly because of capacity challenges of less-developed countries. So far, however, the relationship between human development and capacity challenges for water quality monitoring have not been analysed systematically. This hinders the implementation of fine-tuned capacity development programmes for water quality monitoring. Against this background, this study takes a global perspective in analysing the link between human development and the capacity challenges countries face in their national water quality monitoring programmes. The analysis is based on the latest data on the human development index and an international online survey amongst experts from science and practice. Results provide evidence of a negative relationship between human development and the capacity challenges to meet SDG 6.3.2 monitoring requirements. This negative relationship increases along the course of the monitoring process, from defining the enabling environment, choosing parameters for the collection of field data, to the analytics and analysis of five commonly used parameters (DO, EC, pH, TP and TN). Our assessment can be used to help practitioners improve technical capacity development activities and to identify and target investment in capacity development for monitoring.

Water-efficient agriculture has implied a large increase in energy consumption for irrigation in recent decades. In many irrigation systems, energy costs are now threatening their sustainability. However, new opportunities have arisen for the use of renewable energies in the irrigation sector. These are some of the aspects of the multifaceted multiple-actor ‘waterfoodenergy’ nexus. Technical, economic and environmental issues are linked in many ways, involving farmers, water users’ associations, energy suppliers, engineers and other stakeholders. The ICID session ‘Irrigation and energy’ triggered discussions on these multiple dimensions. This paper presents a synthesis of the presentations, discussions and conclusions. Four main questions are addressed: How do irrigation productivity and sustainability of water resources exploitation change when farmers have access to energy? What do we know about energy efficiency in irrigation systems, at farm and collective network levels? How can this efficiency be optimized by using advanced technologies, modelling tools, improved management? Is energy production an opportunity for irrigation systems? These questions have been posed based on multiple case studies from different parts of the world. The BRL network, in southern France, illustrates advanced strategies and opportunities to reduce energy consumption and develop energy production at a network level. General conclusions are drawn from this synthesis, illustrating trade-offs and synergies that can be identified in the irrigation sector at different scales, while opportunities for future research are proposed.

There is a proactive interest in recovering water, nutrients and energy from waste streams with the increase in municipal wastewater volumes and innovations in resource recovery. Based on the synthesis of wastewater data, this study provides insights into the global and regional “potential” of wastewater as water, nutrient and energy sources while acknowledging the limitations of current resource recovery opportunities and promoting efforts to fast-track highefficiency returns. The study estimates suggest that, currently, 380 billion m3 (m3 = 1,000 L) of wastewater are produced annually across the world which is a volume fivefold the volume of water passing through Niagara Falls annually. Wastewater production globally is expected to increase by 24% by 2030 and 51% by 2050 over the current level. Among major nutrients, 16.6 Tg (Tg = million metric ton) of nitrogen are embedded in wastewater produced worldwide annually; phosphorus stands at 3.0 Tg and potassium at 6.3 Tg. The full nutrient recovery from wastewater would offset 13.4% of the global demand for these nutrients in agriculture. Beyond nutrient recovery and economic gains, there are critical environmental benefits, such as minimizing eutrophication. At the energy front, the energy embedded in wastewater would be enough to provide electricity to 158 million households. These estimates and projections are based on the maximum theoretical amounts of water, nutrients and energy that exist in the reported municipal wastewater produced worldwide annually. Supporting resource recovery from wastewater will need a step-wise approach to address a range of constraints to deliver a high rate of return in direct support of Sustainable Development Goals (SDG) 6, 7 and 12, but also other Goals, including adaptation to climate change and efforts in advancing “netzero” energy processes towards a green economy.

In many parts of the world, wastewater irrigation has become a common practice because of freshwater scarcity and to increase resource reuse efficiency. Wastewater irrigation has positive impacts on livelihoods and at the same time, it has adverse impacts related to environmental pollution. Hydrochemical processes and groundwater behaviour need to be analyzed for a thorough understanding of the geochemical evolution in the wastewater irrigated systems. The current study focuses on a micro-watershed in the peri-urban Hyderabad of India, where farmers practice intensive wastewater irrigation. To evaluate the major factors that control groundwater geochemical processes, we analyzed the chemical composition of the wastewater used for irrigation and groundwater samples on a monthly basis for one hydrological year. The groundwater samples were collected in three settings of the watershed: wastewater irrigated area, groundwater irrigated area and upstream peri-urban area. The collected groundwater and wastewater samples were analyzed for major anions, cations and nutrients. We systematically investigated the anthropogenic influences and hydrogeochemical processes such as cation exchange, precipitation and dissolution of minerals using saturated indices, and freshwater-wastewater mixtures at the aquifer interface. Saturation indices of halite, gypsum and fluorite are exhibiting mineral dissolution and calcite and dolomite display mineral precipitation. Overall, the results suggest that the groundwater geochemistry of the watershed is largely controlled by long-term wastewater irrigation, local rainfall patterns and water-rock interactions. The study results can provide the basis for local decision-makers to develop sustainable groundwater management strategies and to control the aquifer pollution influenced by wastewater irrigation.

Investments in irrigation contribute to poverty reduction and enhance food security. This paper considers irrigation investments more broadly in the context of ruralurban linkages and thus examines rural irrigation schemes and peri-urban and urban agriculture using freshwater, groundwater and wastewater. We present case studies from East, West and Southern Africa, while focusing on the imperative of smallholders and of food security and nutrition. Evidence from Big Data and telecoupling show that, amid global change and sustainability issues, irrigation development strengthens connections between humans and nature with notable benefits to food security. Transforming investments to feed the future generation require priority investments in irrigation, solar energy for groundwater pumping, groundwater development policy, and integration of peri-urban and urban agriculture into food systems. Equally important will be no-regret interventions in wastewater reuse, water storage and groundwater buffer, micro-irrigation, and wholesale reconfiguration of farming systems, through anticipatory investments, to safeguard food security and sustainability into the distant future.

This report builds on prior work to provide a new, comprehensive, and balanced view of water security in Pakistan, stressing the importance of the diverse social, environmental, and economic outcomes from water. The report highlights the complex water issues that Pakistan must tackle to improve water security and sheds new light on conventional assumptions around water. It seeks to elevate water security as an issue critical for national development. The report assesses current water security and identifies important water-related challenges that may hinder progress in economic and human development. It identifies unmitigated water-related risks, as well as opportunities where water can contribute to economic growth and poverty reduction. The report analyzes how the performance and architecture of the water sector are related to broader economic, social, and environmental outcomes. It models alternative economic trajectories to identify where intervention can lead to a more water-secure future. A consideration of water sector architecture and performance and how these determine outcome leads to recommendations for improving aspects of sector performance and adjusting sector architecture for better outcomes. The sector performance analysis considers (a) management of the water resource, (b) delivery of water services, and (c) mitigation of water-related risks. The description of sector architecture considers water governance, infrastructure, and financing.

Black soldier fly colonies can produce about 100 times more protein per year than chicken or soybeans, not to mention cattle, on the same area of land. The flies can directly feed on different types of organic wastes, leapfrogging closed loop processes within a circular food economy. Also, where no protein is needed, for example, to feed fish or pigs, the larvae can be processed into high-quality biodiesel. However, can this be done at scale? The answer is ‘Yes’. The report showcases some of the leading global businesses in Black Soldier Fly production.

In low- and middle-income countries, the management of fecal sludge from on-site sanitation systems has received little attention over many decades, resulting in insufficient or missing regulations to guide investments and management options. To address this gap, this report examines existing and emerging guidelines and regulations for fecal sludge management (FSM) along the sanitation service chain (user interface, containment, emptying, transport, treatment, valorization, reuse or disposal). It also draws empirical examples from guidelines across the globe to support policy-makers, planners, and sanitation and health officers, as well as consultants in low- and middle-income countries in the development and design of local and national FSM guidelines and regulations.

The Arab region needs a new generation of policies and investments in agricultural water. Agricultural water management has always posed challenges and opportunities in the Arab world. However, unprecedented and accelerating drivers such as climate change, population growth, and land degradation make agricultural water management a more urgent priority than ever before. In addition, as part of the 2030 UN Agenda for Sustainable Development, Arab countries have committed to work towards an ambitious set of development targets, the Sustainable Development Goals (SDGs). Unless the right policies and investments are put in place, it will be difficult to achieve the SDGs, including ending hunger and providing clean water and sanitation for all. This paper is part of an ongoing collaboration between the Food and Agriculture Organization of the United Nations (FAO) and the International Water Management Institute to foster dialogue on agricultural water policies and investments in the context of the FAO led Regional Water Scarcity initiative. The purpose of the paper is to frame the key challenges and opportunities in the sector including emerging innovations in digital agriculture, water accounting, water supply and wastewater reuse and to lay out broad strategic directions for action.

Fecal sludge (FS) contains a significant amount of plant nutrients. FS (treated/untreated) has been used as soil ameliorant in several countries. Use of FS-based compost on lettuce may meet reservations due to possible microbiological contamination. The objectives of this research are: (1) To determine the fertilizer value of different formulations of sawdust and fecal sludge compost (SDFS) pellets, and (2) to compare the effect of these SDFS formulations with poultry manure, commercial compost, mineral fertilizer, and non-fertilization on lettuce cultivation. The SDFS products were made by enriching, and pelletized with ammonium sulphate, mineral-NPK, or ammonium sulphate + muriate of potash + triple superphosphate. Lettuce was cultivated in a greenhouse and an open field. The result showed that the saleable fresh weight lettuce yield obtained from all SDFS pellets with/without enrichments were higher than those obtained from commercial compost, poultry manure, mineral fertilizer, or no fertilizer. Cultivation in the open field gave higher yields than those in the greenhouse. No helminth eggs were detected in composts or lettuces. Some fecal coliforms were detected in lettuces fertilized with almost all fertilizers tested, including NPK and non-fertilized control. A properly treated fecal sludge-based fertilizer can be a sustainable solution for lettuce production, which helps urban and peri-urban agriculture.

The Indus River Basin faces severe water quality degradation because of nutrient enrichment from human activities. Excessive nutrients in tributaries are transported to the river mouth, causing coastal eutrophication. This situation may worsen in the future because of population growth, economic development, and climate change. This study aims at a better understanding of the magnitude and sources of current (2010) and future (2050) river export of total dissolved nitrogen (TDN) by the Indus River at the sub-basin scale. To do this, we implemented the MARINA 1.0 model (Model to Assess River Inputs of Nutrients to seAs). The model inputs for human activities (e.g., agriculture, land use) were mainly from the GLOBIOM (Global Biosphere Management Model) and EPIC (Environmental Policy Integrated Model) models. Model inputs for hydrology were from the Community WATer Model (CWATM). For 2050, three scenarios combining Shared Socio-economic Pathways (SSPs 1, 2 and 3) and Representative Concentration Pathways (RCPs 2.6 and 6.0) were selected. A novelty of this study is the sub-basin analysis of future N export by the Indus River for SSPs and RCPs. Result shows that river export of TDN by the Indus River will increase by a factor of 1.62 between 2010 and 2050 under the three scenarios. N90% of the dissolved N exported by the Indus River is from midstream sub-basins. Human waste is expected to be the major source, and contributes by 6670% to river export of TDN in 2050 depending on the scenarios. Another important source is agriculture, which contributes by 2129% to dissolved inorganic N export in 2050. Thus a combined reduction in both diffuse and point sources in the midstream sub-basins can be effective to reduce coastal water pollution by nutrients at the river mouth of Indus.

Globally, many populations face structural and environmental barriers to access safe water, sanitation and hygiene (WASH) services. Among these populations are many of the 200 million pastoralists whose livelihood patterns and extreme environmental settings challenge conventional WASH programming approaches. In this paper, we studied the Afar pastoralists in Ethiopia to identify WASH interventions that can mostly alleviate public health risks, within the populationapos;s structural and environmental living constraints. Surveys were carried out with 148 individuals and observational assessments made in 12 households as part of a Pastoralist Community WASH Risk Assessment. The results show that low levels of access to infrastructure are further compounded by risky behaviours related to water containment, storage and transportation. Additional behavioural risk factors were identified related to sanitation, hygiene and animal husbandry. The Pastoralist Community WASH Risk Assessment visually interprets the seriousness of the risks against the difficulty of addressing the problem. The assessment recommends interventions on household behaviours, environmental cleanliness, water storage, treatment and hand hygiene via small-scale educational interventions. The framework provides an approach for assessing risks in other marginal populations that are poorly understood and served through conventional approaches.

Billions of people currently lack clean water and sanitation. By 2050 the global population will have grown to nearly 10 billion, over two-thirds of whom will live in urban areas. This Voices asks: what are the research and water-management priorities to ensure clean water and sanitation in the world’s cities?

WaterSanitationHygiene (WASH) remains vital for the 2030 Agenda for Sustainable Development, yet many countries have not localised the 17 Sustainable Development Goals (SDGs), including SDG 6, which focuses on ensuring the availability and sustainable management of water and sanitation for all. Even in leading African economies such as South Africa, many communities still use the bucket system for sanitation. Using a Composite Index drawn from three indicators whose data were available for 53 of the 54 African countries, it emerged that these states are at various stages of fulfilling the targets set out in SDG 6. The fact that some countries showed declining trends in WASH between 2000 and 2015, is an indication that it will be difficult for Africa to reach the 2030 targets. We recommend that Africa aggressively mobilise resources if it is to attain universal WASH services by 2030, along with other SDG 6-related targets.

This study applied a combined analytical hierarchy process (AHP) and goal programming (GP) model to assist decision makers in identifying and prioritizing key investment climate (IC) indicators for waste recycling and reuse enterprises in developing countries. Taking a sector based perspective, key IC criteria and indicators were identified and ranked through country stakeholder workshops in Ghana and Kenya. Three different key decision maker groups namely government agencies, private waste reuse enterprises and non-governmental organizations (NGOs) were involved in identifying and ranking of IC criteria and indicators. The IC criteria identified were policy and infrastructure, finance, business support and markets. A number of indicators across each of the criteria were also identified. By incorporating qualitative and quantitative assessments, criteria and indicator rankings are determined using the AHP and GP model. Model results for Ghana revealed that both the private sector and NGO group ranked finance as the most important criterion while markets was the most important criterion for the government organization group. In contrast, none of the stakeholder groups in Kenya ranked finance as the most important criterion. This indicates that reform priorities of waste reuse sector vary across countries depending on the country’s current situation. The approach adopted in this study enables the criteria and indicators for assessing sector specific investment climate to be clearly identified and the decision making problem to be structured systematically. The exercise can be extended to other countries to elicit priority ranking of IC criteria and indicators for waste reuse enterprises.

This study reports and analyzes nutrient balances in experimental vegetable production systems of the two West African cities of Tamale (Ghana) and Ouagadougou (Burkina Faso) over a twoyear period comprising thirteen and eleven crops, respectively. Nutrient-use efficiency was also calculated. In Tamale and Ouagadougou, up to 2% (8 and 80 kg N ha1) of annually applied fertilizer nitrogen were leached. While biochar application or wastewater irrigation on fertilized plots did not influence N leaching in both cities, P and K leaching, as determined with ion-absorbing resin cartridges, were reduced on biochar-amended plots in Tamale. Annual nutrient balances amounted to +362 kg N ha1, +217 kg P ha1, and 125 kg K ha1 in Tamale, while Ouagadougou had balances of up to +692 kg N ha1, +166 kg P ha1, and 175 kg K ha1 y1. Under farmers’ practice of fertilization, agronomic nutrient-use efficiencies were generally higher in Tamale than in Ouagadougou, but declined in both cities during the last season. This was the result of the higher nutrient inputs in Ouagadougou compared to Tamale and relatively lower outputs. The high N and P surpluses and K deficits call for adjustments in local fertilization practices to enhance nutrient-use efficiency and prevent risks of eutrophication.

Groundwater quantity and quality may be affected by climate change through intricate direct and indirect mechanisms. At the same time, population growth and rapid urbanization have made groundwater an increasingly important source of water for multiple uses around the world, including southern Africa. The present study investigates the coupled human and natural system (CHANS) linking climate, sanitation, and groundwater quality in Ramotswa, a rapidly growing peri-urban area in the semi-arid southeastern Botswana, which relies on the transboundary Ramotswa aquifer for water supply. Analysis of long-term rainfall records indicated that droughts like the one in 20132016 are increasing in likelihood in the area due to climate change. Key informant interviews showed that due to the drought, people increasingly used pit latrines rather than flush toilets. Nitrate, fecal coliforms, and caffeine analyses of Ramotswa groundwater revealed that human waste leaching from pit latrines is the likely source of nitrate pollution. The results in conjunction indicate critical indirect linkages between climate change, sanitation, groundwater quality, and water security in the area. Improved sanitation, groundwater protection and remediation, and local water treatment would enhance reliable access to water, de-couple the community from reliance on surface water and associated water shortage risks, and help prevent transboundary tension over the shared aquifer.

Hydropower production is altering the Mekong River basin’s riverine ecosystems, which contain the world’s largest inland fishery and provide food security and livelihoods to millions of people. The basin’s hydropower reservoir storage, which may rise from ~2% of its mean annual flow in 2008 to ~20% in 2025, is attenuating seasonal flow variability downstream of many dams with integral powerhouses and large storage reservoirs. In addition, tributary diversions for off-stream energy production are reducing downstream flows and augmenting them in recipient tributaries. To help manage tradeoffs between dam benefits (hydropower, irrigation, flood control, domestic water supply, and navigation) and their consequences for livelihoods and ecosystems, we review observed and projected impacts on river flows along both the Mekong mainstream and its tributaries. We include the effects of diversions and inter-basin transfers, which prior reviews of flow alteration in the Mekong basin have largely neglected. We also discuss the extent to which concurrent changes in climate, water demand, and land use, may offset or exacerbate hydropower-induced flow alteration. Our major recommendations for assessing hydrological impacts in the Mekong and other basins undergoing rapid hydropower development include synchronizing and integrating observational and modeling studies, improving the accuracy of reservoir water balances, evaluating multi-objective reservoir operating rules, examining hydropeaking-induced flow alteration, conducting multi-dam safety assessments, evaluating flow indicators relevant to local ecosystems and livelihoods, and considering alternative energy sources and reservoir sedimentation in long-term projections. Finally, we strongly recommend that dam impact studies consider hydrological alteration in conjunction with fish passage barriers, geomorphic changes and other contemporaneous stressors.

Natural wetlands are green infrastructure systems that are energy-efficient for wastewater treatment and can be found in diverse geo-environmental settings around the world. Their structure and functions, which defines the treatment efficiencies are highly varied. Wetlands over shallow bedrock and geological lineaments (weak zones) have been known to contribute to groundwater contamination. However, not many studies have been performed to understand the structure in different geological settings to identify the efficiency determining factors. Therefore, it is important to investigate the geological suitability of the natural wetlands. We examined wastewater fed natural wetlands in diverse geological settings aiming at studying the depth, geo-stability, bio-chemical interactions, and hydrogeological attributes that improve the wastewater quality, within the Musi River basin, India. The integrated geophysical scans encompassing electrical resistivity tomography (ERT), hydrogeological test, bathymetric study and hydro-chemical analysis were carried out to explore the physical structure and hydro-dynamic processes in the wetlands. ERT investigations showed that, the depth to bedrock up to 2025 m devoid of geo-fractures (lineaments) indicated the effective depth of saturated zone as a passable scope for potential bio-chemical interactions, implying the proportionality of the deep seated (deep bedrock) wetland to the pollutant removal efficiency. The lower order of electrical resistivity range 1035 Om and hydraulic conductivity 2.938 md-1 acquired for saturated weathered zone were found catalyzing the bioremediation, sedimentation, adsorption, redox reactions and ion exchange processes. It caused the deep seated wetland removing nitrate 194.34 kgd-1 (97.18%); sulphate 333.75 kgd-1 (77.70%); phosphate 9.66 kgd-1 (82.53%); microbes 99.99%, BOD 80%, and COD 80% load with discharge 1408 m3d-1 of treated wastewater. Further, the strategies for designating the natural wetlands as wastewater treatment systems are also discussed in this paper.

A water and soil quality baseline study was carried out across the ~ 4500 km2 Vientiane Plain in Lao PDR. Eight water quality and nine soil parameters were analysed using field kits at 95 sites in March 2015. Elevated electrical conductivity and chloride were apparent at two sites due to geogenic leaching from the marine rock-salt present in some areas. Groundwater was acidic in most locations. Nitrate and faecal contamination were also observed from nitrogenous fertilizers (diffuse) and from leaky sewage pits (localised) respectively. Soil quality is neither nutrient deficient nor does it pose a threat to plant growth. Where groundwater is used for drinking, removal of bacterial contamination by simple filtration or boiling is sufficient. In the absence of a functional monitoring network in the Vientiane Plain, periodic surveys of this kind should be performed. The results should be made widely available to the relevant government departments and other stakeholders for better management of the land and water resources.

Recent studies have examined the urban metabolism of cities using urban consumption as a proxy for food inflows but very few studies have aimed at quantifying the role of cities as trade hubs and nutrient sinks of their hinterlands. We therefore examined the linkages between food and animal feed supply, their places of production and nutrient flows through the urban system in the two West African cities of Tamale (Ghana) and Ouagadougou (Burkina Faso). Using primary data on food and feed flows, and secondary data to assess the transformation of these flows into nutrient terms, we show that, besides urban consumption, the function of the two study sites as trade hubs significantly determines nutrient flows. In Tamale, gt; 50% of the nutrient inflows was neither consumed nor was lost in situ but left that city again for other destinations. At least 30% of the incoming cereals was stored in the city for later consumption or export. Ouagadougou relied more on imported goods with 40% of N imported from foreign countries compared to Tamale where only 10% of the N was imported, thus contributing to heavier nutrient extraction in remote production areas.

This study assesses the microbial and heavy metal distribution in African catfish (Clarias gariepinus) cultured in waste stabilization pond, and their subsequent suitability for human consumption. Treated wastewater-fed pond (WFP) was used in the culture of the fish with a non-wastewater fed pond (NWFP), fed with ground and rain water as control. Pond water, sediments and fish tissue (gill, liver, gut and skin) samples from both sources were analyzed for pathogens and heavy metal levels. Escherichia coli populations in the sediments and water from the WFP exceeded the maximum permissible limit by 23 log units as expected. Significantly higher levels of pathogen contamination were detected in the gut and skin of fish from the WFP than the NWFP. Heavy metal concentrations in all samples fell within the Food and Agricultural Organization (FAO)/World Health Organization (WHO) and National Oceanic and Atmospheric Administration (NOAA) permissible limits except for iron and cadmium. There were significantly higher heavy metal concentrations in gill and liver than the muscle. Even though iron recorded the highest concentrations in fish tissue, the concentrations (0.12.0 mg kg-1) were below the expected daily nutritional requirement (12 mg) for humans and pose no toxicological risk. However, catfish from WFP would require precautionary measures such as cooking/grilling prior to consumption to avoid pathogen infection.

Water availability for agriculture will become a growing constraint in areas already under environmental and social stress due to population growth, development, and climatic variability. This limits the potential for expanding irrigated areas and for sustainable intensification, and compromises the ability of smallholder farmers to cater to the increased demand for food. This chapter assesses the key global challenges to water availability and how increasing scarcity and competition for water resources are affecting agricultural productivity, especially that of smallholder producers in Asia and Africa. It further analyzes emerging water management practices that can be sustainably adapted to the needs of smallholder farmers. We provide evidence of the economic viability and potential to improve farmers’ income from such solutions. The opportunity for scaling up high-impact solutions is also assessed against available empirical evidence.

There is a strong link between gender and energy in view of food preparation and the acquisition of fuel, especially in rural areas. This is demonstrated in a range of case studies from East and West Africa, where biochar, human waste and other waste resources have been used to produce briquettes or biogas as additional high-quality fuel sources. The synthesis of the cases concludes that resource recovery and reuse for energy offers an alternative to conventional centralized grid projects which, while attractive to investors and large-scale enterprises, do not necessarily provide job opportunities for marginalized communities. Reusing locally available waste materials for energy production and as soil ameliorant (in the case of biochar) in small enterprises allows women and youth who lack business capital to begin modest, locally viable businesses. The case studies offer concrete examples of small-scale solutions to energy poverty that can make a significant difference to the lives of women and their communities.

To understand the full value of Resource Recovery and Reuse (RRR), a systematic assessment approach that balances complexity with practicality is required. This report highlights the methods available for quantifying and valuing social, environmental and economic costs and benefits of RRR, focusing on Cost-Benefit Analysis (CBA) as the primary framework. Rather than prescribing a standardized technique for conducting CBA for RRR, this report presents broad frameworks and several examples that can be catered to individual contexts. This results in a suggested eight-step process accompanied with suggested assessment techniques which have to be tailored to the type of question the assessment is meant to answer and related system boundaries.

The safe recovery of nutrients from our waste streams allows us to address the challenges of waste management and soil nutrient depletion conjointly. Commercialization of waste-based organic fertilizers such as FortiferTM (fecal sludge-based co-compost) has the potential to generate significant benefits for developing economies via cost recovery for the sanitation sector and the provision of an alternative agricultural input for smallholder farmers. To guide future FortiferTM businesses, this report presents examples of detailed market assessments, based on farmers’ perceptions, attitudes and willingness-to-pay (WTP) for a pelletized and non-pelletized FortiferTM co-compost. The research was conducted in the Greater Accra and Western regions in Ghana, and in and around Kampala (Uganda), Bangalore (India), Hanoi (Vietnam), and Kurunegala (Sri Lanka). Cross-country analyses helped to understand the effects of market drivers and, where possible, capture lessons learned for knowledge sharing.

Resource recovery and reuse (RRR) of domestic and agro-industrial waste has the potential to contribute to a number of financial, socioeconomic and environmental benefits. However, despite these benefits and an increasing political will, there remain significant barriers to build the required up-front capital which is discouraging private sector engagement. A systematic analysis and understanding of the enabling environment, public and private funding sources, risk-sharing mechanisms and pathways for cost recovery can help to identify opportunities to improve the viability of RRR solutions. This report looks at regulations and policies that remove disincentives for RRR, public and private funding sources for capital and operational costs, risk mitigation options through blending and structuring finance, and options for operational cost recovery.

This report outlines a business model approach to assessing the feasibility and for encouraging investment in smallholder solar pump irrigation. It also proposes a new methodology for mapping the suitability of solar energy-based irrigation pumps. The proposed business model framework and the methodology for suitability mapping are applied to Ethiopia as a case study, based on data from existing case studies and reports. A brief analysis outlines the regulatory and institutional context for investment in solar pump irrigation, and the ways in which it both constrains and attempts to support investment. The report identifies and outlines three business model scenarios that present opportunities for investing in smallholder solar pump-based irrigation, which would contribute towards sustainable intensification for food and nutrition security. The business model scenarios are based on the value proposition of supplying water to smallholder farmers for irrigated agricultural production. Analysis of potential gains and benefits suggests that direct purchase of solar pumps by farmers is feasible, and that out-grower schemes and pump supplier options with bundled financing offer promising solutions. The potential constraints that different investors may face in up-scaling the business models are also discussed, particularly within institutional, regulatory and financial contexts. The report provides development actors and investors with evidence-based information on the suitability and sustainability of solar pump irrigation in Ethiopia, as well as suggestions for helping to enable smallholders to invest in individually-owned, smallholder photovoltaic (PV) solar pumps.

The study is being carried out to investigate the potential for applying SAT in Xaysetha district, Lao PDR and investigation the most suitable site for SAT in Xaysetha district. The methodology was used MCDA, GIS, RRA and semistructured interview to rank SAT site and investigate the physical, social and economic factor at the most suitable site (Nonvay site). The results of SAT ranking indicated that Xaysetha district has a potential to construct up to 3 high suitable site, 8 moderate suitable sites, and 6 low suitable sites. On the other hand, the results of physical, social and economic assessment at Nonvay site represented that DO was exceeded the Lao National Environmental Standard, and the soil infiltration rate is about 24 mm/hour (0.58 m/day). The households around Nonvay site have their own land and they access to water use and have a relationship with 9 organizations. They product wastewater was estimate 150 liter/person/day. And the land available for SAT is worth to US$ 39 million.

Climate change is a complex and cross-cutting problem that needs an integrated and transformative systems approach to respond to the challenge. Current sectoral approaches to climate change adaptation initiatives often create imbalances and retard sustainable development. Regional and international literature on climate change adaptation opportunities and challenges applicable to southern Africa from a water-energy-food (WEF) nexus perspective was reviewed. Specifically, this review highlights climate change impacts on water, energy, and food resources in southern Africa, while exploring mitigation and adaptation opportunities. The review further recommends strategies to develop cross-sectoral sustainable measures aimed at building resilient communities. Regional WEF nexus related institutions and legal frameworks were also reviewed to relate the WEF nexus to policy. Southern Africa is witnessing an increased frequency and intensity in climate change-associated extreme weather events, causing water, food, and energy insecurity. A projected reduction of 20% in annual rainfall by 2080 in southern Africa will only increase the regional socio-economic challenges. This is exacerbating regional resource scarcities and vulnerabilities. It will also have direct and indirect impacts on nutrition, human well-being, and health. Reduced agricultural production, lack of access to clean water, sanitation, and clean, sustainable energy are the major areas of concern. The region is already experiencing an upsurge of vector borne diseases (malaria and dengue fever), and water and food-borne diseases (cholera and diarrhoea). What is clear is that climate change impacts are cross-sectoral and multidimensional, and therefore require cross-sectoral mitigation and adaptation approaches. In this regard, a wellcoordinated and integrated WEF nexus approach offers opportunities to build resilient systems, harmonise interventions, and mitigate trade-offs and hence improve sustainability. This would be achieved through greater resource mobilisation and coordination, policy convergence across sectors, and targeting nexus points in the landscape. The WEF nexus approach has potential to increase the resilience of marginalised communities in southern Africa by contributing towards attaining the Sustainable Development Goals (SDGs 1, 2, 3, 6, 7, and 13).

Wastewater irrigation is a common livelihood practice in many parts of the developing world. With the continuous irrigation supply, groundwater systems in these regions perceive adverse impacts due to inadequate infrastructure to treat the wastewater. The current study area, Musi River irrigation system, is one such case study located in the peri-urban Hyderabad of South India. The Musi River water, which is used for irrigation, is composed of untreated and secondary treated wastewater from Hyderabad city. Kachiwani Singaram micro-watershed in the peri-urban Hyderabad is practicing wastewater irrigation for the last 40 years. The current quality of (untreated) wastewater used for irrigation is expected to have adverse impacts on the local aquifers, but detailed investigations are lacking. To elucidate the groundwater quality dynamics and seasonality of the wastewater irrigation impacts on the peri-urban agricultural system, we analyzed the groundwater quality on a monthly basis for one hydrological year in the wastewater and groundwater irrigated areas, which exist next to each other. The spatio-temporal variability of groundwater quality in the watershed was analyzed with respect to wastewater irrigation and seasonality using multivariate statistical analysis, multi-way modeling and self-organizing maps. This study indicates the significance of combining various statistical techniques for detailed evaluation of the groundwater processes in a wastewater irrigated agricultural system. The results suggest that concentrations of the major ionic substances increase after the monsoon season, especially in wastewater irrigated areas. Multi-way modeling identified the major polluted groundwaters to come from the wastewater irrigated parts of the watershed. Clusters of chemical variables identified by using self-organizing maps indicate that groundwater pollution is highly impacted by mineral interactions and long-term wastewater irrigation. The study recommends regular monitoring of water resources and development of sustainable management strategies to mitigate the aquifer pollution in wastewater irrigation systems.

The Nile Delta and its 2.27 million ha of irrigated land makes up two thirds of Egypt’s agricultural land. It is also the terminal part of a river basin that spans and feeds 11 countries. Increases in dam and irrigation development in upstream parts of the basin is poised to conflict with agricultural expansion and population growth in Egypt. Understanding where and how waters comes into and leaves the delta is therefore a crucial question for the future of the country. This paper revisits the surface and groundwater balances of the delta, emphasizes the additional relevance of drainage water reuse and of the salt balance, and evidences a relative stability of the outflow to the sea over the past 30 years. Various reasons for such a phenomenon and the scope for saving water are explored and discussed. The confusion between plot-level and delta-level efficiency and the relatively limited gains possible are emphasized. Beyond the overall water balance and quantitative issues, water management in the delta remains a complex task of spatially distributing the resource over a complex ramified network. Finally, limitations in the analysis related to data availability and accuracy are emphasized.

Globally, more than 60% of the human population live without safely managed sanitation services or even lack access to basic sanitation facilities. In addition, most of the wastewater produced in the world is discharged without proper treatment. Integrated approaches are needed to address these issues and curb the resulting adverse impacts on public health and the environment, and associated societal economic losses. The UN 2030 SDG Agenda provides an important framework towards more sustainable sanitation development, in terms of both safe sanitation access and wastewater management. Innovative solutions that treat and enable productive safe use of water, and recovery of nutrients and organic matter from wastes resources are booming. Some examples of trends are decentralized solutions, separation of waste flows, low/or no-flushing toilets, and converting faecal sludge to energy. These alternative technologies show huge potential to address many development challenges, contributing to multiple SDGs, but achieving upscaling has proved to be a major challenge. A paradigm shift to ‘treatment for reuse’ instead of ‘treatment for disposal’ is already taking place in the wastewater sector. Nevertheless, a better understanding of driving forces and enabling environment, new organizational models based on more service-oriented sanitation provision, and highlighting potential multiple societal benefits to attract investments from new sectors, are identified areas that need further attention.

The use of wastewater to produce food crops particularly vegetables is very prevalent in Addis Ababa, Ethiopia. This practice may pose health risks to farm workers and consumers. Hence, the study was designed to evaluate farmers’ perceptions on irrigation water quality, health risks and health risk mitigation measures in four wastewater-irrigated urban vegetable farming sites in Addis Ababa. Data were collected on farm through 263 individual interviews and 12 focus group discussions. The findings showed that despite differences in levels of knowledge and awareness on health risks, farmers appear informed about the contamination of their irrigation water. The difference in perception to quality consideration of Akaki River/irrigation water is highlighted by the result of KruskalWallis H test analysis which shows significant mean value (1.33) of positive perception toward the water quality by male than female farmers. Interestingly, significant difference (p lt; 0.05) in mean values of awareness toward problems of eating unwashed vegetables is also found between male and female farmers where females seemed to be more aware. Conversely, no significant difference was found in mean value of perception and awareness toward vegetables quality. Among the perceived health risks, skin problems were top-rated health risk while eye burn, sore feet and abdominal pains were rated low across the four farming sites. Although statistically not significant, perception toward consumption-related health risk differed with gender: females assigned relatively high mean score. Irrespective of the farming site and gender differences, the most accepted health risk reduction measures were health promotion programs and cessation of irrigation before harvesting. In view of crop restriction measures, females assigned significantly (p = 0.044) low mean score to planting non-food produce. Akaki-Addis farmers suitability perceptions of planting non-food produce and non-raw eaten crops were significantly (p lt; 0.001) higher than the other farming sites. Therefore, effective site and gender-specific educational programs have the potential for clarifying farmers and consumers’ risks and risk management perceptions and improving practical knowledge, which in turn may help identify adoption barriers, opportunities and incentives.

Water and nutrition are linked in multiple ways, but few of these interlinkages are well understood. What is, for example, the exact relationship between water pollution and health or between water resource management and nutrition? Even less is known about the interactions across these various linkages. The importance of better understanding these connections has been highlighted as we pursue the United Nations Sustainable Development Goals (SDGs), which challenge mankind to meet both water security as well as food and nutrition security goals, while also improving water-based ecosystems. It has become increasingly clear that progress toward these goals can only be achieved if measures in the food and nutrition space (SDG 2) do not constrain progress on water (SDG 6) and if measures undertaken to support targets under one of these SGDs also support the outcomes of the other. This paper provides an overview of waternutrition linkages as reflected in the SDGs, and it identifies key gaps in these linkages and suggests a way forward to support the achievement of both water and nutrition goals and targets.

This Atlas summarizes recent advances in interdisciplinary approaches and research to address the different components of West African urban food systems, including urban and peri-urban agriculture. It thereby draws on the results of several major collaborative research projects and stakeholder consultations conducted in West Africa over the past two decades, and in particular on the UrbanFoodPlus project in Ghana and Burkina Faso (www.urbanfoodplus.org). The publication targets with its innovative design a broad range of stakeholders.

Current patterns of agricultural expansion and intensification are bringing unprecedented environmental externalities, including impacts on water quality. While water pollution is slowly starting to receive the attention it deserves, the contribution of agriculture to this problem has not yet received sufficient consideration. We need a much better understanding of the causes and effects of agricultural water pollution as well as effective means to prevent and remedy the problem. In the existing literature, information on water pollution from agriculture is highly dispersed. This repost is a comprehensive review and covers different agricultural sectors (including crops, livestock and aquaculture), and examines the drivers of water pollution in these sectors as well as the resulting pressures and changes in water bodies, the associated impacts on human health and the environment, and the responses needed to prevent pollution and mitigate its risks.

This chapter reviews the main pollutants from agriculture, its associated impacts, and offers some key pollution mitigation options. The chapter also discusses how agriculture can be a beneficial user of wastewater, and how the practice can become safe.

Nutrients and water found in domestic treated wastewater are valuable and can be reutilized in urban agriculture as a potential strategy to provide communities with access to fresh produce. In this paper, this proposition is examined by conducting a field study in the rapidly developing city of Hyderabad, India. Urban agriculture trade-offs in water use, energy use and GHG emissions, nutrient uptake, and crop pathogen quality are evaluated, and irrigation waters of varying qualities (treated wastewater, versus untreated water and groundwater) are compared. The results are counter-intuitive, and illustrate potential synergies and key constraints relating to the foodenergywaterhealth (FEWhealth) nexus in developing cities. First, when the impact of GHG emissions from untreated wastewater diluted in surface streams is compared with the life cycle assessment of wastewater treatment with reuse in agriculture, the treatment-plus-reuse case yields a 33% reduction in life cycle system-wide GHG emissions. Second, despite water cycling benefits in urban agriculture, only lt;1% of the nutrients are able to be captured in urban agriculture, limited by the small proportion of effluent divertible to urban agriculture due to land constraints. Thus, water treatment plus reuse in urban farms can enhance GHG mitigation and also directly save groundwater; however, very large amounts of land are needed to extract nutrients from dilute effluents. Third, although energy use for wastewater treatment results in pathogen indicator organism concentrations in irrigation water to be reduced by 99.9% (three orders of magnitude) compared to the untreated case, crop pathogen content was reduced by much less, largely due to environmental contamination and farmer behavior and harvesting practices. The study uncovers key physical, environmental, and behavioral factors that constrain benefits achievable at the FEW-health nexus in urban areas.

Agricultural productivity and farm household welfare in areas of severe land degradation can be improved through ecosystem-based interventions. Decisions on the possible types of practices and investments can be informed using evidence of potential benefits. Using farm household data together with a farm level stochastic simulation model provides an initial quantification of farm income and nutrition outcomes that can be generated over a five year period from manure and compost based organic amendment of crop lands. Simulated results show positive income and nutrition impacts. Mean farm income increases by 13% over the planning period, from US$32,833 under the business as usual situation (application of 50 kg DAP and 25 kg urea ha- 1 yr- 1) to US$37,172 under application of 10 t ha- 1 yr- 1 farm yard manure during the first three years and 5 t ha- 1 yr- 1 during the last two years. As a result of organic soil amendment, there is an associated increase in the available calorie, protein, fat, calcium, and iron per adult equivalent, giving the improvement in farm household nutrition. The evidence is substantive enough to suggest the promotion and adoption at scale, in degraded ecosystems, of low cost organic soil amendment practices to improve agricultural productivity and subsequent changes in farm household welfare.

In recent years, interest in fuel briquetting increased because of the opportunity to utilise agricultural residues and the organic fractions of municipal solid waste for energy, with a potential reduction in environmental pollution levels, and where modern heating and cooking fuels for domestic, institutional, commercial and industrial use are not readily available or affordable.

Urban and rural households in low income countries rely on traditional biomass fuels such as charcoal and firewood for cooking and heating purposes, which has an adverse effect on forest resources and on people’s health. A major reason for people to continue these as main sources of fuel for cooking is lack of affordable and reliable alternative sources of energy. Briquettes present a great opportunity to replace traditional biomass fuels for domestic and institutional cooking and industrial heating processes. Through designing and implementing a viable briquette business model, we emphasise that there is a commercial case for the briquette business in Ghana.

Recovering energy, nutrients and water from domestic and agro-waste streams is gaining momentum as a new agenda for promoting sustainable development in developing countries as waste management strategies shift focus from a disposal-oriented approach to a business-oriented approach. The latter approach emphasises value creation and revenue generation (Murray and Buckley, 2010). As most cities in developing countries struggle with the challenge of energy security, recovering energy from different waste streams offers dual benefits improved waste management and provision of reliable energy to households, institutions and commercial entities.

The main purpose of this paper is to estimate farmers’ preferences and their willingness to pay (WTP) for ecosystem services derived from four agricultural water management (AWM) and resource recovery and reuse (RRR) intervention options in Burkina Faso, using a choice experiment (CE). These include; small water infrastructure, drip irrigation, recovery of organic matter from waste, and treated wastewater. The design decisions relating to attribute selection, the level of attributes, alternatives and choice tasks were guided by literature, field visits, focus group discussions, expert input and an iterative process of the STATA software to generate an orthogonal main-effects CE design. The data used was generated from a random sample of 300 farm households in the Dano and Ouagadougou municipalities in Burkina Faso. Results from conditional logit, latent class logit and mixt logit models show that farmers have positive and significant preferences for drip irrigation, treated wastewater, and organic matter. However, they are WTP on average more for drip irrigation and organic matter for agricultural sustainability. In line with economic theory, the cost of an intervention reduces demand for a given intervention. These findings can provide policy makers with evidence for agricultural policy design to build farmers’ resilience in the Sahel.

There is a great potential to close the nutrient recycling loop, support a ‘circular economy’ and improve cost recovery within the waste sector and to create viable businesses via the conversion of waste to organic fertilizers. Successful commercialization of waste-based organic fertilizer businesses however largely depends on a sound market. We used a choice experiment to estimate farmers’ willingness-to-pay (WTP) for faecal sludge and municipal solid waste-based (FSM) compost in Kampala, Uganda and considered three attributesfortification, pelletization and certification. Our results reveal that farmers are willing to pay for FSM compost and place a higher value on a ‘certified’ compost product. They are willing to pay US $0.4 per kg above the current market price for a similar certified product, which is 67 times higher than the cost of providing the attribute. Farmers are willing to pay US $0.127 per kg for ‘pelletized’ FSM compost, which is lower (0.57 times) than the cost of providing the attribute. On the other hand, farmers require US $0.089 per kg as a compensation to use ‘fortified’ FSM compost. We suggest that future FSM compost businesses focus on a ‘certified and pelletized’ FSM product as this product type has the highest production costWTP differential and for which future businesses can capture the highest percentage of the consumer surplus. The demand for FSM compost indicates the benefits that can accrue to farmers, businesses and the environment from the recycling of organic waste for agriculture.

A choice experiment was used to assess households’ willingness-to-pay (WTP) for informational attributes (sources of water used to rear sh, and certi cation) of sh products in Hanoi, Vietnam. The study showed that households’ purchasing decisions are in uenced by their access to information of food product attributes and ascribe an economic value to it. The results indicated that households are willing to pay 51% (USD 1.11 per kg) above the prevailing market price of sh for information to know if wastewater is used to rear the sh they consume. Similarly, they are willing to pay 20% above the prevailing market price of sh (USD 0.43 per kg) to know if freshwater is used as a rearing medium. It is important to note that the increased marginal WTP is for information on whether the sh they consume is raised in wastewater over freshwater. This supports the notion of households’ concern over the safety of consuming wastewater-raised sh. Households are also willing to pay 65% (USD 1.42 per kg) above the prevailing market price for certi ed sh. Based on the cost of sh certi cation and WTP estimates, we found a total economic bene t of USD 172 million for the implementation of a wastewater-raised sh business model in Hanoi. The demand for wastewater-raised sh is likely to be affected by households’ perception of certi cation by a trusted government agency, source of water used to raise the sh, age, income and household size.

When urban areas expand without concomitant increases in wastewater treatment capacity, vast quantities of wastewater are released to surface waters with little or no treatment. Downstream of many urban areas are large areas of irrigated croplands reliant on these same surface water sources. Case studies document the widespread use of untreated wastewater in irrigated agriculture, but due to the practical and political challenges of conducting a true census of this practice, its global extent is not well known except where reuse has been planned. This study used GIS-based modeling methods to develop the first spatially-explicit estimate of the global extent of irrigated croplands influenced by urban wastewater flows, including indirect wastewater use. These croplands were further classified by their likelihood of using poor quality water based on the spatial proximity of croplands to urban areas, urban wastewater return flow ratios, and proportion of wastewater treated. This study found that 65% (35.9 Mha) of downstream irrigated croplands were located in catchments with high levels of dependence on urban wastewater flows. These same catchments were home to 1.37 billion urban residents. Of these croplands, 29.3 Mha were located in countries with low levels of wastewater treatment and home to 885 million urban residents. These figures provide insight into the key role that water reuse plays in meeting the water and food needs of people around the world, and the need to invest in wastewater treatment to protect public health.

Co-composted dewatered faecal sludge (FS) with organic fractions of municipal solid waste (MSW) has a high potential to be used as an agricultural resource in Sri Lanka. In addition to options for cost recovery in waste management, closing the nutrient and carbon cycles between urban and rural areas, substitution of mineral fertilizers, reduced pollution. and the restoration of degraded arable land are possible with important benefits. Up to now little is known about the usage of FS-MSW as fertilizer and it needs to be studied in order to achieve a better understanding and generate application recommendations. The aim of these experiments has been to evaluate the possibility of substituting mineral fertilization. Two field experiments were conducted on sandy loam to assess the effects of MSW compost and FS-MSW co-compost, its pelletized forms, and mineral-enriched FS-MSW on crop growth. As a short-term crop Raphanus sativus “Beeralu rabu” (radish) was studied for 50 days in a randomized complete block design (RCDB). Results show that, under drought conditions, FS-MSW co-compost increased the yield significantly, while MSW and FS-MSW compost enabled the highest survival rate of the plants. Similarly, the second field trial with a long-term crop, Capsicum anuum “CA-8” (capsicum), was planted as RCBD, using the same treatments, for a cultivation period of 120 days. Results display that during a drought followed by water saturated soil conditions co-compost treatments achieved comparable yields and increased the survival rate significantly compared to the control, fertilized with urea, triple super phosphate, and muriate of potash. Cost-benefit analysis (CBA) revealed that pelletizing decreased the monetary benefits if only fertilizer value is considered. It can be concluded that, under drought and water stress, co-compost ensures comparable yields and enables more resistance, but might not be economical viable as a one-crop fertilizer. These findings need to be validated with further trials under different climate regimes and soils.

Recovering nutrients, water and energy from domestic waste streams, including wastewater and faecal sludge, is slowly gaining momentum in low-income countries. Resource recovery and reuse (RRR) offers value beyond environmental benefits through cost recovery. An expected game changer in sanitation service provision is a business model where benefits accrued via RRR can support upstream sanitation services despite the multitude of private and public stakeholders involved from waste collection to treatment. This paper shows options of how resource recovery and reuse can be an incentive for the sustainable sanitation service chain, by recovering costs where revenue can feed back internally or using generated revenues from reuse to fill financial gaps across the service chain to complement other supporting mechanisms for making waste management more attractive.

Background: Wastewater irrigation for vegetable production is a highly prevalent practice in Addis Ababa and a number of articles have been published on wastewater-irrigated soils and vegetables contaminated with heavy metals. However, to the best of our knowledge, an insight into assessment of human health risks associated with the consumption of vegetable crops grown on wastewater-irrigated soils is non-existent in the city. Long-term effect of wastewater irrigation on the build-up of heavy metals in soils and selected vegetable crops in Addis Ababa urban vegetable farming sites (10) was evaluated. By calculating estimated daily intakes (EDIs) and target hazard quotients (THQs) of metals, health risk associated with the consumption of the analyzed vegetables was also evaluated.; Results: The heavy metal concentrations in irrigation water and soils did not exceed the recommended maximum limits (RMLs). Moreover, Cd, Co, Cr, Cu, Ni and Zn concentrations in all analyzed vegetables were lower than the RML standards. In contrast, Pb concentrations were 1.43.9 times higher. Results of two way ANOVA test showed that variation in metals concentrations were significant (p lt; 0.001) across farming site, vegetable type and site x vegetable interaction. The EDI and THQ values showed that there would be no potential health risk to local inhabitants due to intake of individual metal if one or more of the analyzed vegetables are consumed. Furthermore, total target hazard quotients (TTHQs) for the combined metals due to all analyzed vegetables were lower than 1, suggesting no potential health risk even to highly exposed local inhabitants.; Conclusions: There is a great respite that toxic metals like Pb and Cd have not posed potential health risk even after long term (more than 50 years) use of this water for irrigation. However, intermittent monitoring of the metals from irrigation water, in soil and crops may be required to follow/prevent their build-up in the food chain.

The study was to assess the: (i) effect of human urine and other organic inputs on cabbage growth, yield, nutrient uptake, N-use efficiency, and soil chemical characteristics; (ii) economic returns of the use of urine and/or other organic inputs as a source of fertiliser for cabbage production. To meet these objectives, participatory field trials were conducted at Dzorwulu, Accra. Four different treatments (Urine alone, Urine + dewatered faecal sludge (DFS), Urine + poultry droppings (PD), NPK (15-15-15) + PD) were applied in a Randomised Complete Block Design (RCBD) with soil alone as control. Each treatment was applied at a rate of 121 kgNha-1 corresponding to the Nitrogen requirement of cabbage in Ghana. Growth and yield parameters, plant nutrient uptake, and soil chemical characteristics were determined using standard protocols. There were no significant differences between treatments for cabbage head weight, or total and marketable yields. However, unmarketable yield from NPK + PD was 1 to 2 times higher (p lt; 0.05) than those from Urine + PD, Urine + DFS, and Urine alone. Seasonal effect on yields was also pronounced with higher (p lt; 0.001) cabbage head weight (0.95 kg) and marketable yields (12.7 kgha-1) in the dry season than the rainy season (0.42 kg and 6.27 kgha-1). There was higher (p lt; 0.005) phosphorous uptake in cabbage from Urine + PD treated soil than those from other treatments. Nitrogen (N), phosphorous (P), and potassium (K) uptake in the dry season was significantly higher than the rainy season. Soils treated with Urine + DFS and Urine + PD were high in total N content. Urine + PD and Urine + DFS treated soils gave fairly high yield than PD + NPK with a net gain of US$1452.0 and US$1663.5, respectively. The application of urine in combination with poultry droppings has the potential to improve cabbage yields, nutrient uptake, and soil nitrogen and phosphorous content.

The study analyses dis-adoption of biogas technologies in Central Uganda. Biogas technology makes use of livestock waste, crop material and food waste to produce a flammable gas that can be used for cooking and lighting. Use of biogas technology has multiple benefits for the households since it reduces the need for fuelwood for cooking and also produces bio-slurry which is a valuable fertilizer. Despite efforts by Government and Non-Governmental Organizations to promote the biogas technology, the rate of its adoption of biogas technology was found to be low, estimated at 25.8% of its potential. A review of literature showed that the households that dis-adopted biogas technology, did so within a period of 4 years after its installation, yet the lifespan of using it is estimated at 25 years. There was need to examine the factors contributing to dis-adoption. Using cross sectional data collected from Luwero and Mpigi districts found in Central Uganda, a probit model was estimated. The findings showed that an increase in the family size, the number of cattle, number of pigs and the age of the household head reduced the likelihood of biogas technology dis-adoption. Other factors that contributed to dis-adoption included the failure to sustain cattle and pig production that are necessary for feedstock supply, reduced availability of family labor the and inability of the households to repair biogas digesters after malfunctioning. Based on the findings, it was concluded that long term use of biogas technology required improved management practices on the farm so as to sustain livestock production. It is also recommended that quality standards and socio-cultural factors be considered in the design of biogas digesters and end use devices.

The government of Bangladesh is increasingly paying attention to the safe collection and disposal of fecal sludge from pit latrines in rural areas. In this paper, we report on current sludge disposal practices from single-pit latrines, by conducting a survey of 1,091 households with pit latrines in a rural subdistrict of Bangladesh. Almost all households were using their pits, and 90% reported that hiring pit emptiers to empty the pit for reuse was the dominant pit management practice. However, 90% of households also reported that the sludge from these pits would be disposed of in the vicinity of their homes, by digging wide and shallow troughs in the soil to absorb the sludge. These results indicate an urgent need to design an organized service that safely transports fecal sludge away for treatment. The National Committee for Fecal Sludge Management, constituted by the government of Bangladesh, is using these results to design policy for sludge management.

Motivation: Proper management of fecal sludge has significant positive health and environmental externalities. Most research on managing onsite sanitation so far either simulates the costs of, or the welfare effects from, managing sludge in situ in pit latrines. Thus, designing management strategies for onsite rural sanitation is challenging, because the actual costs of transporting sludge for treatment, and sources for financing these transport costs, are not well understood.; Methods: In this paper we calculate the actual cost of sludge management from onsite latrines, and identify the contributions that latrine owners are willing to make to finance the costs. A spreadsheet-based model is used to identify a cost-effective transport option, and to calculate the cost per household. Then a double-bound contingent valuation method is used to elicit from pit-latrine owners their willingness-to-pay to have sludge transported away. This methodology is employed for the case of a rural subdistrict in Bangladesh called Bhaluka, a unit of administration at which sludge management services are being piloted by the Government of Bangladesh.; Results: The typical sludge accumulation rate in Bhaluka is calculated at 0.11 liters/person/day and a typical latrine will need to be emptied approximately once every 3 to 4 years. The costs of emptying and transport are high; approximately USD 13 per emptying event (circa 14% of average monthly income); household contributions could cover around 47% of this cost. However, if costs were spread over time, the service would cost USD 4 per year per household, or USD 0.31 per month per householdcomparable to current expenditures of rural households on telecommunications.; Conclusion: This is one of few research papers that brings the costs of waste management together with financing of that cost, to provide evidence for an implementable solution. This framework can be used to identify cost effective sludge management options and private contributions towards that cost in other (context-specific) administrative areas where onsite sanitation is widespread.

Purpose: Faecal sludge (FS) has been co-composted with many organic solid wastes globally. Agricultural wastes, such as oil palm empty fruit bunches (EFB) and cocoa pod husks (CPH), have received very little research attention as far as combining with FS is concerned. This study aimed at co-composting these wastes at different ratios to produce safe compost for use as soilless medium for raising tomato transplants.; Methods: Dewatered FS (DFS) was mixed with shredded EFB and CPH at five different ratios: 1DFS:1EFB, 1DFS:1CPH, and DFS:EFB:CPH in ratios of 1:1:1, 2:1:1, and 2:2:1 and composted for 3 months. Select physicochemical parameters and pathogens were monitored every fortnightly and 3 weeks, respectively.; Results: Maximum temperatures obtained ranged 46.854.5 C. Though these temperatures were lower than sanitizing temperatures prescribed by USEPA, no E. coli was found in any of the piles at the end of composting. The ratio 2DFS:2EFB:1CPH was found to be the safest formulation and hence was used to grow tomato under greenhouse conditions. Tomato seeds were sown in three different growing media: 100% FS-based compost, 100% rice husk biochar, and 50% FS-based compost50% rice husk biochar mix.; Conclusion: Results showed that FS-based compost was a suitable growing medium for tomato. Further studies into the optimal rate and frequency of application of compost teas on tomato are recommended.

Background: In Addis Ababa, where irrigation water for vegetable production is commonly derived from the highly polluted Akaki river, information on microbial contamination of water and irrigated vegetable is scanty. An assessment was done to determine the microbiological quality of irrigation water and lettuce harvested from 10 urban farming sites of Addis Ababa. The efficacy of 5 lettuce washing methods were also assessed. A total of 210 lettuce and 90 irrigation water samples were analyzed for faecal coliform and helminth eggs population levels.; Results: The mean faecal coliform levels of irrigation water ranged from 4.29-5.61 log10 MPN 100 ml-1, while on lettuce, the concentrations ranged from 3.46-5.03 log10 MPN 100 g-1. Helminth eggs and larvae were detected in 80% of irrigation water and 61% of lettuce samples. Numbers ranged from 0.9-3.1 eggs 1000 ml-1 and 0.8-3.7 eggs 100 g-1 wet weight for irrigation water and lettuce, respectively. The helminth eggs identified included those of Ascaris lumbricoides, Hookworm, Enterobius vermicularis, Trichuris trichiura, Taenia and Strongloyides larvae. Ascaris lumbricoides and Hookworm were most prevalent in both irrigation water and lettuce samples. Compared with the WHO recommendations and international standards, the faecal coliform and helminth eggs levels in irrigation water and lettuce samples exceeded the recommended levels. Irrespective of the tested washing methods, faecal coliform and helminth eggs levels were somehow reduced. Among the washing methods, potable tap water washing - rinsing (2 min) followed by dipping in 15 000 ppm vinegar solution for a minute supported the highest faecal coliorm reduction of 1.7 log10 units, whereas lowest reduction of 0.8 log10 units was achieved for the same procedure without vinegar.; Conclusion: Compared with international standards, both faecal coliform and helminth eggs levels exceeded recommended thresholds in water and lettuce, but still in a potential risk range which can be easily mitigated if farmers and households are aware of the potential risk. Aside preventing occupational exposure, potential risk reduction programs should target households which have so far no guidance on how best to wash vegetables. The result of the present study suggest that the vinegar based washing methods are able to reduce faecal coliform towards low level while the physical washing with running water may help to substantially decrease potential risk of helminth parasitic infections.

Background: Faecal matter biochar offers an interesting value proposition where the pyrolysis process guaranties a 100% pathogen elimination, as well as significant reduction in transport and storage weight and volume. Therefore, to evaluate the effect of (1) biochar produced from dried faecal matter from household based septic tanks, and (2) N fertilizer, as well as their interaction on yield and nutrient status of lettuce (Lactuca sativa), lettuce was grown over two growing cycles under glasshouse on two contrasting soils amended once at the start with factorial combination of faecal matter biochar at four rates (0, 10, 20 and 30 t ha-1) with 0, 25 and 50 kg N ha-1 in randomized complete block design.; Results: For both soils, maximum fresh yields were recorded with biochar and combined application of biochar with N treatments. However, the greatest biochar addition effects (with or without N) with regard to relative yield were seen in less fertile sandy loam soil. We have also observed that faecal matter biochar application resulted in noticeable positive residual effects on lettuce yield and tissue nutrient concentrations in the 2nd growing cycle. For both soils, most nutrients analyzed (N, P, K, Mg, Cu and Zn) were within or marginally above optimum ranges for lettuce under biochar amendment.; Conclusions: The application of faecal matter biochar enhances yield and tissue nutrient concentrations of lettuce in two contrasting soils, suggesting that faecal matter biochar could be used as an effective fertilizer for lettuce production at least for two growing cycles. Moreover, the conversion of the faecal matter feedstock into charred product may offer additional waste management benefit as it offers an additional (microbiologically safe) product compared to the more common co-composting.

Biogas (anaerobic digestion) technology is one of the most viable renewable energy technologies today. However, its economic efficiency depends on the investment costs, costs of operating the biogas plant and optimum methane production. Likewise the profit level also rests on its use directly for cooking or conversion into electricity. The present study assessed the economic potential for a 9000 m3 biogas plant, as an alternative to addressing energy and environmental challenges currently in Ghana. A cost-benefit analysis of the installation of biogas plant at University of Ghana (Legon Sewerage Treatment Plant) yielded positive net present values (NPV) at the prevailing discount rate of 23%. Further the results demonstrate that installation of the plant is capital intensive. Biogas used for cooking was by far the most viable option with a payback period (PBP) of 5 years. Sensitivity analysis also revealed cost of capital, plant and machinery as the most effective factors impacting on NPV and internal rate of return (IRR).

Most cities in developing countries fail to treat their wastewater comprehensively. Consequently, farmers downstream use poor-quality water for irrigation. This practice implies risks for farmers, consumers and the environment. Conversely, this water supply supports the livelihood of these farmers and other stakeholders along the value chains. Linking safer options for wastewater management with irrigation could therefore be a winwin solution: removing the risks for society and maintaining the bene ts for farmers. However, in developing countries, the high investment costs for the required treatment are problematic and the willingness of farmers to pay for the water (cost recovery) is often questionable. Using a choice experiment, this paper gives insight into farmers’ preferences for wastewater use scenarios, quantifying their willingness to pay. The case study is Hyderabad, India. Farmers there prefer water treatment and are prepared to pay a surplus for this. Considering the costrecovery challenge, this information could be valuable for planning small on site wastewater treatment systems.

Energy efficient wastewater treatment systems are the current environmental concerns which prompted for the applications of natural wetlands as efficient systems at urban areas. However, a detailed investigation is highly desired to determine the efficiency determining factors relevant to structure and functions of natural wetlands for enhanced wastewater treatment. In view of this the wastewater fed natural wetland is examined by hydro-geophysical means, to decipher i) the effective depth of physico-chemical and microbial reactions, ii) the saturated zone thickness, and iii) hydrogeological attributes enhancing the wastewater quality at Hyderabad city, India. The wetland has been scanned using electrical resistivity tomography (ERT) to decipher its physical structure, and hydrogeological and biogeochemical investigations are performed to understand the dynamics. The low electrical resistivity ( =10.5-34.0 O-m) and moderate hydraulic conductivity (K=2.938 m/d) acquired for saturated zone (1015 m depth), are found the wastewater enhancing parameters in the wetlands. Geophysically derived laterally constrained inversion (LCI) models explore the maximum saturated zone of wetland up to 25 m as an effective depth for pollutant removal mechanisms. It implies the proportionality between depth to bed rock (confining layer) and wetland efficiency. Further, the bio-geochemical scanning determines the bioremediation, sedimentation, adsorption, redox reactions and ion exchange processes as wetland functions for removing nutrients (77-97%), BOD (78%), COD (76%), and microbes (99.5-99.9%) load with the discharge Q=1812 m3d-1 of treated wastewater. Further, the wetland efficiency integrated with engineered interventions help develop various NTS models with different application scenarios, that are i) constructed wetlands, ii) minimized community wetlands, and iii) single outlet system, suitable for urban, peri-urban and rural areas, respectively. The socio-economic assessment, and farmer-consumers and stakeholders survey suggest that to test and use of wetland systems implementation as a policy guideline under sustainable water management.

Healthy soils are essential for productive and resilient agricultural systems. They are also increasingly recognized as a means to mitigate climate change risks. While solutions for restoring degraded soils and landscapes do exist, improved knowledge and tools are needed to enhance their impacts over time and at scale. WLE has assessed the impacts of various land restoration initiatives and developed a range of tools to better tailor and target investments and interventions to local contexts.

The International Water Management Institute (IWMI) is a non-pro t, scienti c research organization focusing on the sustainable use of water and land resources in developing countries. IWMI works in partnership with governments, civil society and the private sector to develop scalable agricultural water management solutions that have a real impact on poverty reduction, food security and ecosystem health. IWMI is a member of CGIAR, a global research partnership for a food-secure future.

The water, energy, and food resources share a lot in common; they have strong interdependencies and are inadvertently affected by action in any one of them. Therefore, the nexus approach (integrated policies related to water, energy, and food) is required in the face of growing concerns over the future availability and sustainability of these resources. The nexus approach can help achieve at least some of the “Sustainable Development Goals (SDGs)” (e.g., SDG 2, 6, 7, 12, 13, 15). This chapter discusses trends in availability and consumption of the three key resources (i.e., water, energy, and food) and interactions between them, and finally provides some reasons why the nexus approach can help achieve social and economic development goals.

The chapter discusses how adopting a holistic methodology that acknowledges socio-logical factors, including community participation, public involvement, social perception, attitudes, gender roles and public acceptance, would lead to improvements in wastewater management practice. It highlights the social dimension as a tool, a lens through which wastewater management and reuse can take on new dimensions. In this way, this chapter aims to shift the focus from perceiving wastewater as a nuisance that needs disposal, toward a resource not to be wasted, which can contribute to food security, human and environmental health, access to energy as well as water security.

Recovering energy from waste offers dual benefits a) improved waste management, and b) provision of reliable energy to households, institutions and commercial entities. In this report, we present a socioeconomic assessment of three energy business models (briquette manufacturing, on-site (public toilet) energy generation, and agro-waste electricity generation) based on feasibility studies carried out in the city of Kampala, Uganda. We assess the potential economic, environmental and social impacts of waste-to-energy business models taking into consideration a life cycle of emissions to provide decision makers with the overall costs and benefits of the models to society versus a business-as-usual scenario.

Recycling and reuse of treated wastewater are an important part of the sanitation cycle and critical in an environment such as urban India with decreasing freshwater availability and increasing costs for delivering acceptable quality water, often from far distance. This report has been developed as a possible guidance document for the Indian government and gives substantial focus to the financial and economic benefits of wastewater recycling from the perspective of public spending. The report presents possible strategies for city and state planners and policymakers in view of the sanitation situation and the role of wastewater recycling in the larger cities in India (class I and II cities and towns with populations above 50,000), and focuses on recycling at the end of sewerage systems after treatment at sewage treatment plants.

Where modern heating and cooking fuels for domestic, institutional, commercial and industrial use are not readily available, briquettes made from biomass residues could contribute to the sustainable supply of energy. This study reviews the briquette making process, looking at the entire value chain starting from the type and characteristics of feedstock used for briquette making to the potential market for briquettes in developing countries. It also analyzes the role that gender plays in briquette production. Depending on the raw materials used and technologies applied during production, fuel briquettes come in different qualities and dimensions, and thus require appropriate targeting of different market segments. Key drivers of success in briquette production and marketing include ensuring consistent supply of raw materials with good energy qualities, appropriate technologies, and consistency in the quality and supply of the briquettes. Creating strong partnerships with key stakeholders, such as the municipality, financiers and other actors within the briquette value chain, and enabling policy are important drivers for the success of briquette businesses.

On-site sanitation systems, such as septic tanks and pit latrines, are the predominant feature across rural and urban areas in most developing countries. However, their management is one of the most neglected sanitation challenges. While under the Millennium Development Goals (MDGs), the set-up of toilet systems received the most attention, business models for the sanitation service chain, including pit desludging, sludge transport, treatment and disposal or resource recovery, are only emerging. Based on the analysis of over 40 fecal sludge management (FSM) cases from Asia, Africa and Latin America, this report shows opportunities as well as bottlenecks that FSM is facing from an institutional and entrepreneurial perspective.

Biological treatment, composting, in particular, is a relatively simple, durable and inexpensive alternative for stabilizing and reducing biodegradable waste. Co-composting of different waste sources allows to enhance the compost nutrient value. In particular, integration of ‘biosolids’ from the sanitation sector as potential input material for co-composting would provide a solution for the much needed treatment of fecal sludge from on-site sanitation systems, and make use of its high nutrient content. This research paper elaborates in detail the main parameters that govern the co-composting process as well as factors that control the production of a safe and valuable quality compost. It further explains technological options to tailor the final product to crop and farmer needs.

Although the Ganges River Basin (GRB) has abundant water resources, the seasonal monsoon causes a mismatch in water supply and demand, which creates severe water-related challenges for the people living in the basin, the rapidly growing economy and the environment. Addressing these increasing challenges will depend on how people manage the basin’s groundwater resources, on which the reliance will increase further due to limited prospects for additional surface storage development. This report assesses the potential of the Ganges Water Machine (GWM), a concept proposed 40 years ago, to meet the increasing water demand through groundwater, and mitigate the impacts of floods and droughts. The GWM provides additional subsurface storage (SSS) through the accelerated use of groundwater prior to the onset of the monsoon season, and subsequent recharging of this SSS through monsoon surface runoff. It was identified that there is potential to enhance SSS through managed aquifer recharge during the monsoon season, and to use solar energy for groundwater pumping, which is financially more viable than using diesel as practiced in many areas at present. The report further explores the limitations associated with water quality issues for pumping and recharge in the GRB, and discusses other related challenges, including availability of land for recharge structures and people’s willingness to increase the cropping intensity beyond the present level.

As in other cities of Sri Lanka, solid waste management has been a key problem in and concern for Balangoda Urban Council. Waste accumulations in the city have caused many problems, including unpleasant odours, contamination of water bodies, and contamination of paddy fields, giving rise to epidemic diseases such as Salmonella, typhoid fever, and diarrhoea. A Balangoda compost plant has been set up to process municipal solid waste into compost. The project started in 1999 as a city service to provide a solution to the solid waste problem, but converted into a business in later years. Integrated waste management in Balangoda now consists of a Municipal Solid Waste compost plant, septage treatment plant, plastic pelletiser and an open dump. In addition, as there is increasing awareness of environmental and health risks related to the use of agro-chemical fertilisers, demand for alternative organic fertilisers is increasing. As per the majority of the compost plants in the country, the Balangoda plants are located in semi-urban or rural areas, facilitating reuse of waste in agriculture, with farming areas located near the compost plants. The Balangoda system thus operationalises rural-urban linkages through the collection of urban food and organic waste and its recycling, sale, and reuse as compost for rural (and peri-urban) producers.

Wastewater irrigaon is not new in Maharashtra and the Government of Maharashtra as well as farmers are beginning to recognize its value as a drought response. This Highlight presents a synthesis of eld exploraons in 11 locaons in Maharashtra which cover the extent of wastewater irrigaon; economics of wastewater and freshwater use; farmersapos; preferences and percepons about wastewater; and how they are adapng to its use in agriculture.

Groundwater quality is gaining more importance in groundwater management due to rapid growth in population, agriculture and industrial sectors worldwide. The goal of the present study is to evaluate the groundwater chemistry and to identify the geochemical processes governing the water chemistry in the shallow uncon ned and deeper con ned aquifers in the Eastern Ganges Basin using geochemical methods. Groundwater samples were analysed for major ions and metals (Fe, Mn, Zn, Cu, Pb and As). Shallow wells are found to have high pH, EC, TDS, Ca, Mg, Cl and SO4, and low HCO3/Cl ratio compared to the deep wells. However, the average concentration of Na, HCO3, NO 3, PO 4, F and Mn is not signi cantly varied with depth which indicates that the variation in the water chemistry between uncon ned and con ned aquifers is not only due to the natural processes but also indicates that surface contamination sources could have affected the water chemistry in the uncon ned aquifer. In the uncon ned aquifer, processes like wastewater in ltration, denitri cation, reverse ion exchange and mineral weathering govern the water chemistry. The water chemistry in the con ned aquifer is regulated by weathering of silicate and carbonate minerals and regional ow.

Fecal sludge (FS) contains significant amounts of plant nutrients and organic matter although it also contains pathogens. Therefore, FS can be used as fertilizer after proper sanitization. This study was designed to test dried fecal sludge (DFS)-based pellet fertilizers on maize cultivation. The DFS fertilizers were produced by composting, co-composting with sawdust, or irradiated by gamma-irradiation, and then nitrogen-enriched and pelletized using gelatinized or gamma-irradiated cassava starch. These DFS pellet fertilizers were compared to each other and to no-fertilization, mineral fertilizer, and agro-industrial waste compost. The fertilizer applications were 150 or 210 kgN/ha. Maize was cultivated in pots containing Cambisol and Ferric Lixisol growth media. The EC-SDFS-PG pellet (DFS + sawdust co-composted, enriched with nitrogen and pelletized) at a rate of 210 kgN/ha produced the highest maize yield (4.4 ton/ha) among all other treatments, while mineral fertilizer produced 3.9 ton/ha. It is concluded that the EC-SDFS-PG pellet produces similar or higher maize yields than mineral fertilizer and more than the agro-industrial compost in both growth media types.

With increasing pressures from global changes (urbanization, climate change, etc.), cities in Africa will experience difficulties in efficiently managing water resources. Most of the urbanization in Africa over the next 30 years will occur in fast-growing small towns that lack mature infrastructure. This offers a unique opportunity to implement innovative solutions based on integrated urban water management (IUWM). While IUWM approaches have been widely reported in the literature, their application has been limited. This paper describes the African Water Facility’s experience in applying the approach to three projects, in the Seychelles, Zimbabwe and Democratic Republic of Congo, which illustrate the types of challenges faced in different institutional frameworks and contexts (such as islands, a small town and a megacity). The paper identifies the critical issues for improving uptake and scaling up, including strong leadership, the commitment of government and the institutions involved, and a formal programme of capacity building and technical assistance.

Appropriate canopy management, including planting density and pruning, and application of fertilizer may increase flowering success and seed and oil yields of Jatropha curcasL.Twofieldexperimentswereperformedfrom2009to 2011 in Balaka, Malawi, to assess the effect of planting density and pruning regime and single fertilizer application (N, P, and K) on male and female flower number and seed and oil yields of J. curcas. Planting density influenced flower sex ratio and female flower number. Branch pruning treatments did not influence the flower sex ratio but reduced seed and final oil yield by 55 % in the following year. It is claimed that J.curcas can be grown on soils with low nutrient content, but this study revealed that yield was low for non-fertilized trees. WeobservedhigherseedandoilyieldsathigherNapplication rates(upto20342%seedand20445%oilyieldincrease) compared with the non-fertilized control. The study suggests thatcurrentlyusedheavypruningpracticeisnotrecommended for J.curcas cultivation, although it needs further longer term investigation. Applying nitrogen fertilizer is effective in increasing yield.

In response to changing urban food systems, short supply chains have been advocated to meet urban food needs while building more sustainable urban food systems. Despite an increasing interest in urban food supply and the flows of food from production to consumption, there is a lack of empirical studies and methodologies which systematically analyse the actual proportion and nutritional significance of local and regional food supplied to urban markets. The aim of this empirical study therefore was to compare the geographical sources supplying food to the urban population (“foodsheds”) in Tamale, Ghana and Ouagadougou, Burkina Faso, to record the supplied quantities and to assess the level of interaction between the sources and the respective city. The study was conducted over two years, covering the seasons of abundant and short supply, via traffic surveys on the access roads to the two cities, and in the Tamale markets, resulting altogether in more than 40,000 records of food flow. Results indicated that food sources were highly crop- and season-specific, ranging from one-dimensional to multi-dimensional foodsheds with diverse sources across seasons. Across the commodity-specific foodsheds, city region boundaries were established. Within the proposed city region a relatively large proportion of smallholders contributed to urban food supply, taking advantage of the proximity to urban markets. While food provided from within the city region offers certain place-based benefits, like the provision of fresh perishable crops, a larger geographical diversity of foodsheds appeared to enhance the resilience of urban food systems, such as against climate related production failures.

Safe emptying and disposal of fecal sludge from pit latrines in rural areas has become a priority for the Government of Bangladesh. In this paper, we calculate the volume and characterize the hazards of managing sludge to identify technologies for safely emptying rural single pits. In Bhaluka subdistrict, an estimated 15,000 m3 of sludge is produced annually. Physical, chemical, and microbial analysis of samples of sludge taken from pit latrines indicate that the sludge has a high moisture content of around 90%, a C:N ration of 10:1, and a helminth presence of 41 eggs/g. In a field test of alternative emptying technologies, simple pumps such as the gulper emerged as feasible for use in rural areas, due to the liquid nature of the sludge, narrow roads, and limited incomes of rural households. The results suggest that current practices of emptying liquid sludge manually without any protective equipment poses risks to those who handle sludge, and the process needs to be semi-mechanized with immediate effect. These results are being used by the Bangladesh government to design policy for sludge management. In the near future, an organized service that safely empties single pits and transports sludge for treatment needs to be urgently designed.

The study was carried out to assess the efficacy of a standard Biofil toilet digester with regard to its effluent quality and to evaluate the performance of new effluent polishing options being developed by BiofilCom. Infuent and effluent were collected from 18 standard Biofil digesters connected to full- flush toilets. Effluent from five pilot installations with improved effluent polishing options were also taken for analyses. Ten other Biofil installations were selected to assess the impact of digester effluent discharge on the surrounding soil. Pollutant concentrations in the Biofil effluent exceeded both Ghana EPA and WHO standards for discharge though pollutant removal efficiencies were high: 84% for biochemical oxygen demand, 86.1% for chemical oxygen demand and 82.4% for total suspended solids. Escherichia coli and total coliform levels were signi cantly reduced by 63% and 95.6%, respectively, and nutrients were the least removed from effluents. Generally, effluents from the majority of the pilot polishing options met most of the discharge standards. E. coli were present in the soil at all study sites, except one. Biofil digester effluent is discharged subsurface but comparing their effluent quality with standards for discharge into water courses is relevant especially in areas of frequent flooding and high water tables.

Tamale is the capital city of Ghana’s Northern Region. As the regional capital, Tamale is growing rapidly the population has almost tripled to over 370,000 in the past 30 years, and the areal extent has increased up to sevenfold in the same period. Urban agriculture is an integral part of the food system, linked to resource management and spatial planning. In general one can say that backyard farming flourishes, but more formally organised production is threatened by urbanisation.

In Tanzania like in other parts of the global South, in the name of apos;developmentapos; and apos;poverty eradicationapos; vast tracts of land have been earmarked by the government to be developed by investors for different commercial agricultural projects, giving rise to the contested land grab phenomenon. In parallel, Integrated Water Resources Management (IWRM) has been promoted in the country and globally as the governance framework that seeks to manage water resources in an efficient, equitable and sustainable manner. This article asks how IWRM manages the competing interests as well as the diverse priorities of both large and small water users in the midst of foreign direct investment. By focusing on two commercial sugar companies operating in the Wami-Ruvu River Basin in Tanzania and their impacts on the water and land rights of the surrounding villages, the article asks whether institutional and capacity weaknesses around IWRM implementation can be exploited by powerful actors that seek to meet their own interests, thus allowing water grabbing to take place. The paper thus highlights the power, interests and alliances of the various actors involved in the governance of water resources. By drawing on recent conceptual insights from the water grabbing literature, the empirical findings suggest that the IWRM framework indirectly and directly facilitates the phenomenon of water grabbing to take place in the Wami-Ruvu River Basin in Tanzania.

Purpose: The purpose of this paper is to explore people’s perceptions, stated attitudes, and observed and reported behaviour to water and other environmental quality. Design/methodology/approach: The study adopted a mixed method approach. It employed a cross-sectional survey design. Ten communities were selected in Accra and its surrounding communities to indicate various levels of infrastructure provision and environmental quality. Four separate focus group discussions (FGDs) were carried out in each community, with a mixed group of older and young adult men and women, a group of men only, a group of women only, and a group of young adults only. Following the FGDs, further information was obtained through structured household questionnaire survey involving 443 respondents. Findings: Different ideas were employed to explain people’s perceptions of water quality. There were common ideas such as on health, history of water use, perceptions which affect water use, and management of community activities which affect water sources. These ideas which emerged from the focus groups helped participants to assign meaning to their environment. Reported behaviour was influenced by the ability to pay for services, their availability and the influence of shared community norms. Although citizen participation in water and environmental management decision making was very limited, community collective action can be harnessed to enhance water and other environmental management. Originality/value: Adopted an interdisciplinary approach that enabled explanations to phenomenon to emerge from the perspectives of the society rather than views being suggested to them. Thus, resulting in evidence-based issues for intervention.

The resolution adopted by the General Assembly of the United Nations on 25 September 2015 is symptomatic of the water-energy-food (WEF) nexus. It postulates goals and related targets for 2030 that include (1) End hunger, achieve food security and improved nutrition, and promote sustainable agriculture (SDG2); (2) Ensure availability and sustainable management of water and sanitation for all (SDG6); and (3) Ensure access to affordable, reliable, sustainable, and modern energy for all (SDG7). There will be tradeoffs between achieving these goals particularly in the wake of changing consumption patterns and rising demands from a growing population expected to reach more than nine billion by 2050. This paper uses global economic analysis tools to assess the impacts of long-term changes in fossil fuel prices, for example, as a result of a carbon tax under the UNFCCC or in response to new, large findings of fossil energy sources, on water and food outcomes. We find that a fossil fuel tax would not adversely affect food security and could be a boon to global food security if it reduces adverse climate change impacts.

Phosphorus (P) is a critical, geographically concentrated, nonrenewable resource necessary to support global food production. In excess (e.g., due to runoff or wastewater discharges), P is also a primary cause of eutrophication. To reconcile the simultaneous shortage and overabundance of P, lost P flows must be recovered and reused, alongside improvements in P-use efficiency. While this motivation is increasingly being recognized, little P recovery is practiced today, as recovered P generally cannot compete with the relatively low cost of mined P. Therefore, P is often captured to prevent its release into the environment without beneficial recovery and reuse. However, additional incentives for P recovery emerge when accounting for the total value of P recovery. This article provides a comprehensive overview of the range of benefits of recovering P from waste streams, i.e., the total value of recovering P. This approach accounts for P products, as well as other assets that are associated with P and can be recovered in parallel, such as energy, nitrogen, metals and minerals, and water. Additionally, P recovery provides valuable services to society and the environment by protecting and improving environmental quality, enhancing efficiency of waste treatment facilities, and improving food security and social equity. The needs to make P recovery a reality are also discussed, including business models, bottlenecks, and policy and education strategies.

Groundwater quality receives increasing attention in water management in India. The purpose of this paper is to highlight the emerging issues of groundwater quality in the Ramganga Sub-Basin (RSB), a tributary joining the Ganga River from the northern plains, which extends over 30,839 Sq. km and covers 15 districts in both Uttarakhand and Uttar Pradesh. The groundwater in most of the districts of the RSB has high concentration of nitrate, iron, salinity and fluoride, which exceed the standards prescribed for drinking water by the Bureau of Indian Standards (BIS) and World Health Organization (WHO). Arsenic contamination in groundwater is an emerging issue in few groundwater development blocks. Moreover, groundwater with substantial hardness, high sulfate, and high manganese is emerging issue in some districts. Additionally, shallow aquifers have high concentration of ions. In the RSB, the quality of groundwater, especially in the shallow aquifers, is influenced by the contamination of poor quality surface water, due mainly to poor sanitation, improper disposable of domestic sewage water, manures and irrigation return flows. To reduce deterioration of water quality further, the RSB requires proper sanitation facilities, efficient usage of agrochemicals, as well as an awareness program of water-related disease.

To assess the efficiency of seven treatments including biochars produced from dried faecal matter and manures as stabilizing agents of cadmium (Cd)-spiked soils, lettuce was grown in glasshouse on two contrasting soils. The soils used were moderately fertile silty loam and less fertile sandy loam and the applied treatments were 7 % w/w. The reduction of bioavailable Cd (ammonium nitrate extractable) and its phytoavailability for lettuce were used as assessment criteria in the evaluation of stabilization performance of each treatment. Moreover, the agronomic values of the treatments were also investigated. Ammonium nitrate extraction results indicated that faecal matter biochar, cow manure biochar and lime significantly reduced bioavailable Cd by 8487, 6568 and 8291 %, respectively, as compared to the spiked controls. Unpredictably, coffee husk biochar induced significant increment of Cd in NH4NO3 extracts. The immobilization potential of faecal matter biochar and lime were superior than the other treatments. However, lime and egg shell promoted statistically lower yield and P, K and Zn concentrations response of lettuce plants compared to the biochar treatments. The lowest Cd and highest P tissue concentrations of lettuce plants were induced by faecal matter and cow manure biochar treatments in both soils. Additionally, the greatest Cd phytoavailability reduction for lettuce was induced by poultry litter and cow manure biochars in the silty loam soil. Our results indicate that faecal matter and animal manure biochars have shown great potential to promote Cd immobilization and lettuce growth response in heavily contaminated agricultural fields.

Low-impact development (LID) comprises a broad spectrum of stormwater management technologies for mitigating the impacts of urbanization on hydrological processes. Among these technologies, green roofs are one of the most adopted solutions, especially in densely populated metropolitan areas, where roofs take up a significant portion of the impervious surfaces and land areas are scarce. While the in situ hydrological performance of green roofsi.e., reduction of runoff volume and peak dischargeis well addressed in literature, less is known about their impact on stormwater management and reuse activities at a catchment or city scale. This study developed an integrated urban water cycle model (IUWCM) to quantitatively assess the effect of uniform green roof deployment (i.e., 25, 50, and 100% conversion of traditional roofs) over the period 20092011 in the Marina Reservoir catchment, a 100-km2, highly urbanized area located in the heart of Singapore. The IUWCM consists of two components: (1) a physically based model for extensive green roofs integrated within a one-dimensional numerical hydrological-hydraulic catchment model linked with (2) an optimization-based model describing the operation of the downstream, stormwater-fed reservoir. The event-based hydrological performance of green roofs varied significantly throughout the simulation period with a median of about 5% and 12% for the catchment scale reduction of runoff volume and peak discharge (100% conversion of traditional roofs). The high variability and lower performance (with respect to temperate climates) are strongly related to the tropical weather and climatic conditionse.g., antecedent dry weather period and maximum rainfall intensity. Average annual volume reductions were 0.6, 1.2, and 2.4% for the 25, 50, and 100% green roof scenarios, respectively. The reduction of the stormwater generated at the catchment level through green roof implementation had a positive impact on flood protection along Marina Reservoir shores and the energy costs encountered when operating the reservoir. Vice versa, the drinking water supply, which depends on the amount of available stormwater, decreased due to the evapotranspiration losses from green roofs. Better performance in terms of stormwater reuse could only be obtained by increasing the time of concentration of the catchment. This may be achieved through the combination of green roofs with other LID structures.

Wastewater is increasingly regarded as a valuable resource, but to fully and safely exploit the potential, sound institutional arrangements governing its reuse are crucial. This article presents a case study of a self-managed irrigation scheme in Western Cape, South Africa, that uses treated effluent directly, formally and safely. By applying the Institutional Analysis and Development framework, the variables within the context, action arena and patterns of interaction that have enabled this outcome are systematically identified and evaluated. Key variables include: water scarcity; an effective policy and regulatory framework; public pollution prevention awareness; self-organization; and capital-intensive water use linked to profitable markets.

During the past decades, many composting projects have been implemented with the assistance from various donor agencies to address the municipal solid waste (MSW) problem in developing countries, especially in urban areas. However, very few of these projects are sustainable and many were reported as failures, some even closed down and most ofexisting operations rely on heavy subsidies from the Government, foreign funding sources and Local Authorities (LAs). To enhance solid waste management (SWM) an initiative called quot;Pilisaruquot; project started in 2008 lead by the Central Environmental Authority (CEA) to develop the infrastructures of LAs for a better S WM system mainly focllsing on composting as an efficient low cost option for treatment of the organic waste fraction. However, the initial assessment of this initiative encountered many issues. Therefore, this study was proposed to identifY main lactors that affect the sustainability of municipal compost plants. The methods used to obtain data for this research comprise, sample survey that involved five selected compost plants operating under LAs in Sri Lanka; a specific lield survey that observed waste segregation activities: and a cl ients perception survey conducted in a super market in Colombo that aimed to assess customers perspective 011 buying and use ofcompost based Iquot;bod products. To supplement the findings ofthese investigations, a complementary literature revie\ and selected expert interviews were carried out with representative stakeholders. The research findings indicate that most of LAs do not have the needed expertise to design, implement and manage an integrated S WM system that allows efticient operation of compost plants according to recognized standards. Furthermore, it appears that 1110st ofthe compost plants do not manage it full-cost recovery of their Oamp;M cost with the main issues that users are not charged for the provided waste management services and .produced compost can not be marketed successfully, Besides, from the perspective of sustainable operation, need and provision offuture investment is unclear, especially for replacement to maintain an effective operation level. To overcome the emerging weaknesses of the Pilisaru project, it is recommended to provide a continuous capacity building programme for the LAs and involved stakeholders, supported by public awareness programs, especially lor enhanced waste segregation, marketing promotion for compost products as well as technical and financial assistance for relevant stakeholders that need support to perform their tasks in the SW value chain. Furthermore, it is envisioned to revisit the provided SWM policies and to add regulations that built on insights from best SWM practices in Sri Lanka but also from applicable international experiences from other developing countries. This should also include the production of quality compost that meets the fertilizer demands from an agriculture perspective. Lastly, th

The UN recognition of a human right to water for drinking, personal and other domestic uses and sanitation in 2010 was a political breakthrough in states’ commitments to adopt a human rights framework in carrying out part of their mandate. This chapter explores other domains of freshwater governance in which human rights frameworks provide a robust and widely accepted set of normative values to such governance. The basis is General Comment No. 15 of the Committee on Economic, Social and Cultural Rights in 2002, which states that water is needed to realise a range of indivisible human rights to non-starvation, food, health, work and an adequate standard of living and also procedural rights to participation and information in water interventions. On that basis, the chapter explores concrete implications of the Comment for states’ broader infrastructure-based water services implied in the recognised need to access to infrastructure, rights to non-discrimination in public service delivery and respect of people’s own prioritisation. This implies a right to water for livelihoods with core minimum service levels for water to homesteads that meet both domestic and small-scale productive uses, so at least 50100 l per capita per day. Turning to the state’s mandates and authority in allocating water resources, the chapter identifi es three forms of unfair treatment of smallscale users in current licence systems. As illustrated by the case of South Africa, the legal tool of “Priority General Authorisations” is proposed. This prioritises water allocation to small-scale water users while targeting and enforcing regulatory licences to the few high-impact users.

Wastewater may be defined as the combination of liquid wastes discharged from domestic households, farms, institutions, and commercial and industrial establishments eventually mixed with groundwater, surface water, and stormwater. Wastewater is increasingly receiving global attention as it is seen as one of the alternative solutions to increasing global water scarcity. Indeed, wastewater is globally being reused in many applications including groundwater recharge, industrial reuse like for cooling, environmental and recreational uses, nonpotable urban uses, and indirect or direct potable reuse. However, agricultural irrigation and landscaping is by far the largest wastewater use sector. Indeed, millions of farmers worldwide are involved in wastewater irrigation activities. However, wastewater contains a variety of pollutants and contaminants, which may pose health risks if not well managed. These pollutants include salts, metals, metalloids, pathogens, residual drugs, organic compounds, endocrine disruptor compounds, and active residues of personal care products. The kind and extent of health risks depend on many factors including the types and levels of contaminants as well as regional risk relevance. In low-income countries, risks from pathogens receive the most attention. This is because people in these countries are most affected by diseases caused by poor sanitation such as diarrheal diseases and helminth infections, so high loads of pathogenic microorganisms are often found in wastewater systems. Focusing on low-income contexts, this chapter presents health risks posed by wastewater irrigation activities and some practical examples on how these risks could be managed.

Although wastewater has been increasingly used to grow a range of crops for income generation and livelihood resilience in urban and peri-urban areas, irrigation with untreated or partially treated wastewater may result in negative impacts on irrigated crops, soils, and groundwater along with implications for human and environmental health through chemical and microbial risks. With the potential for environmental risks due to concentrations above the maximum allowable levels, the major chemical constituent groups that need to be addressed in wastewater-irrigated environments are metals and metalloids, essential nutrients, salts and specific ionic species, and persistent organic pollutants. To avoid potential negative impacts, conventional wastewater treatment options, which can control the release of these contaminants into the environment, remain the key to protecting water quality for beneficial uses in agriculture, aquaculture, and agroforestry systems. Effective legislation, monitoring, and enforcement are also essential and often neglected management strategies. At the farm level, some low-cost irrigation, soil, and crop management options, discussed in this chapter, are available to reduce the risk from contaminants added through wastewater irrigation.

With increasing change of traditional diets, and the emergence of new supply and marketing chains, urban food consumers in low-income countries are faced with multiple food safety challenges, among which microbial contamination and pesticides are key concerns for fruits and vegetables sold on urban markets in West Africa. Although consumers have a genuine interest in healthy food, and are willing to pay premiums, their interpretation of food quality and risks deviates from scientific health risk assessments and does not translate into recommended risk mitigation behavior. To safeguard public health, alternative measures are needed to support consumers’ risk awareness and decision making. The review looked at common and less-common options to trigger and support behavioral change, including safety labeling (certification), corporate social responsibility models, incentive systems and social marketing of safe practices, to address potential food safety risks from farming in urban and peri-urban areas. Overall, it appears that regulatory measures for risk management, including certifications, will be for now less effective in the West African setup due to low educational levels in view of chemical and microbial risk, diverse and often informal food chains, poor safety supporting infrastructure and weak institutional capacities for compliance monitoring.

The report summarizes key results from surveys carried out on urban and peri-urban agriculture (UPA) in Tamale (Ghana) and Ouagadougou (Burkina Faso) in 2013. The aim was to provide a broad overview of the state of UPA in the study cities and a basis for future research endeavors. The randomized sampling approach used aerial photography to identify 10 sites in different categories of farm in each city. Farmers provided information on their cropping and livestock-rearing activities. There were similarities between the cities, but the differences in the expression of UPA in Tamale and Ouagadougou were more intriguing, as in farm sizes, crops grown and livestock ownership. Farmers were particularly concerned about diminishing access to land in Tamale, where sales by chiefs to private investors were accelerating. In Ouagadougou, formal reallocation of land to homeowners by the state had similarly decreased available farmland. Water availability was a universal concern, and the quality of water used for irrigation was potentially more questionable in Ouagadougou than in Tamale. The results point to the need for further work on uncontaminated, perennial water sources and soil fertility management, alongside focuses on commercialization of animal production, and the legal, political and institutional context of UPA in different West African cities.

Thirsty and hungry cities are posing significant challenges for the urban-rural interface ranging from food security to inter-sectoral water allocation. Not only is the supply of resources to urban centres a growing challenge in low-income countries, but even more is the urban return flow, as investments in waste management and sanitation, ie the ‘ultimate food waste’, are not able to keep pace with population growth. And where polluted water is used in irrigation to feed the cities, food safety is becoming a crucial component of food security. Most affected by resource competition and pollution are the urban and peri-urban farming systems which are often driven by the informal sector. Urban waste is not only a challenge but also offers opportunities. It is in this interface between agriculture and sanitation where the CGIAR operates through its research programme on Water, Land and Ecosystems (WLE), addressing both the challenges and opportunities of urbanisation: by exploring novel perspectives and solutions to respond to changing population dynamics, resource demands, centralised water and nutrient flows, and ecosystem services under pressure.

The paper investigates the current practices of the green economy, and challenges and opportunities in the Limpopo Province of South Africa. The paper is based on a baseline study designed to gather data from key informants in Limpopo provincial, district and local municipalities. Twenty-three key informants in the province were interviewed. Primary data collected from key informants was supplemented by secondary data from document reviews. Descriptive statistics were used to analyse data on the current practices of green economy, and challenges and opportunities in the province. Findings from the study suggest that there is generally significant awareness of the green economy concept across the provincial district and local municipalities in Limpopo Province. However, there are gaps in terms of information gathering, storage and sharing on green economy activities in the district municipalities, provincial and national departments. The main barriers constraining the implementation of green economy initiatives in the municipalities include lack of information; shortage of workers with full knowledge on green economy; shortage of training programmes on green economy; and costs of implementation. The main recommendations from this research include the need to improve awareness of green economy activities across all levels in the province, especially with communities’ need for evidence-based research to demonstrate the potential of green economy activities that can contribute to job creation and poverty reduction; and training of officials on how the green economy can contribute to addressing developmental challenges such as service delivery, job creation, local economic development and poverty reduction.

This study assesses the impact of the Productive Safety Net Program (PSNP) on farmersapos; investments in sustainable land management (SLM) practices in the Central Rift Valley (CRV) of Ethiopia. Primary data were collected using a structured and pre-tested questionnaire for a sample of 159 households (82 PSNP participants and 77 non-participants) in four kebeles (the lowest administrative unit in Ethiopia) of two weredas (districts). Using a cross-sectional household survey, propensity score matching (PSM) was used to assess the impact of PSNP on householdsapos; investments in soil erosion control and soil fertility management. The PSM results show that the control group of households (non-participants in PSNP) invested more in soil erosion control measures as compared to the treated group of households (participants in PSNP). On the contrary, however, the treated group of households significantly invested more in soil fertility management practices (e.g. inorganic fertilizer and compost) as compared to the control group of households. The negative impact of PSNP on households’ investments in soil erosion control in the treated group of farmers is related to their high labor investment in public works, which is not the case for the non-participants in PSNP. This implies that PSNP should pay more attention to capacity building and awareness raising, which requires a restructuring of the program that would benefit long-term and more sustainable impact on reducing food insecurity and enhancing natural resources in the CRV of Ethiopia.

Wastewater constitutes an alternative water source for the irrigation sector. To fully benefit from it, and reduce possible adverse effects on public health and the environment, we need to look at the regulation of the practice. A prerequisite for this is an institutional analysis, and the points to consider are the institutional mandates. We used the city of Hyderabad, India, as a case study. There, irrigation with wastewater is not supported or recognized, but it happens in practice. It takes place in an indirect and unplanned way. Institutions fail at enforcing regulations, and little attention is given to formalization of the practice. With this article, we aim to untangle the institutional setup, and by doing so, identify the constraints surrounding development of a formal practice. Ultimately, we aim at contributing to the discussion on the agricultural use of wastewater.

This paper presents an application of integrated methodological approach for identifying cost-effective combinations of agri-environmental measures to achieve water quality targets. The methodological approach involves linking hydro-chemical modelling with economic costs of mitigation measures. The utility of the approach was explored for the River Dee catchment in North East Scotland, examining the cost-effectiveness of mitigation measures for nitrogen (N) and phosphorus (P) pollutants. In-stream nitrate concentration was modelled using the STREAM-N and phosphorus using INCA-P model. Both models were first run for baseline conditions and then their effectiveness for changes in land management was simulated. Costs were based on farm income foregone, capital and operational expenditures. The costs and effects data were integrated using ‘Risk Solver Platform’ optimization in excel to produce the most cost-effective combination of measures by which target nutrient reductions could be attained at a minimum economic cost. The analysis identified different combination of measures as most costeffective for the two pollutants. An important aspect of this paper is integration of model-based effectiveness estimates with economic cost of measures for cost-effectiveness analysis of land and water management options. The methodological approach developed is not limited to the two pollutants and the selected agri-environmental measures considered in the paper; the approach can be adapted to the cost-effectiveness analysis of any catchment-scale environmental management options.

In many urban and peri-urban areas of India, wastewater is under-recognized as a major water resource. Wastewater irrigated agriculture provides direct benefits for the livelihoods and food security of many smallholder farmers. A rapidly urbanizing peri-urban micro-watershed (270 ha) in Hyderabad was assessed over a 10-year period from 2000 to 2010 for changes in land use and associated farming practices, farmer perceptions, socio-economic evaluation, land-use suitability for agriculture and challenges in potential irrigated area development towards wastewater use. This integrated approach showed that the change in the total irrigated area was marginal over the decade, whereas the built-up area within the watershed boundaries doubled and there was a distinct shift in cropping patterns from paddy rice to paragrass and leafy vegetables. Local irrigation supplies were sourced mainly from canal supplies, which accounted for three-quarters of the water used and was largely derived from wastewater. The remainder was groundwater from shallow hard-rock aquifers. Farmer perception was that the high nutrient content of the wastewater was of value, although they were also interested to pay modest amounts for additional pre-treatment. The shift in land use towards paragrass and leafy vegetables was attributed to increased profitability due to the high urban demand. The unutilised scrubland within the watershed has the potential for irrigation development, but the major constraints appear to be unavailability of labour and high land values rather than water availability. The study provides evidence to support the view that the opportunistic use of wastewater and irrigation practices, in general, will continue even under highly evolving peri-urban conditions, to meet the livelihood needs of the poor driven by market demands, as urban sprawl expands into cultivable rural hinterlands. Policy support is needed for enhanced recognition of wastewater for agriculture, with flow-on benefits including improved public health and protection of ecosystem services.

Risk assessments related to use of water and safety of fresh produce originate from both water and food microbiology studies. Although the set-up and methodology of risk assessment in these 2 disciplines may differ, analysis of the current literature reveals some common outcomes. Most of these studies from the water perspective focus on enteric virus risks, largely because of their anticipated high concentrations in untreated wastewater and their resistance to common wastewater treatments. Risk assessment studies from the food perspective, instead, focus mainly on bacterial pathogens such as Salmonella and pathogenic Escherichia coli. Few site-specific data points were available for most of these microbial risk assessments, meaning that many assumptions were necessary, which are repeated in many studies. Specific parameters lacking hard data included rates of pathogen transfer from irrigation water to crops, pathogen penetration, and survival in or on food crops. Data on these factors have been investigated over the last decade and this should improve the reliability of future microbial risk estimates. However, the sheer number of different foodstuffs and pathogens, combined with water sources and irrigation practices, means that developing risk models that can span the breadth of fresh produce safety will be a considerable challenge. The new approach using microbial risk assessment is objective and evidence-based and leads to more flexibility and enables more tailored risk management practices and guidelines. Drawbacks are, however, capacity and knowledge to perform the microbial risk assessment and the need for data and preferably data of the specific region.

Effective facilitation enables farmer-based water user organizations to analyse contextual issues, identify causal links, formulate clear challenges, develop partnerships with stakeholders, and innovate and implement solutions. However, facilitation is often provided by international partners, such as advanced research institutions or non-governmental organisations (NGOs). The reliance on external consultants to facilitate innovation and change processes creates risks for sustainability. This article provides an overview of a capacity development initiative for facilitation of change in the agriculture water sector in Africa. It focuses on the case study of the Improved Management for Agricultural Water in East and Southern Africa (IMAWESA) network’s learning alliance on facilitating community engagement. The IMAWESA learning alliance sought to build competency on facilitation methods and tools at national and sub-national levels within and across agricultural water management projects. The paper primarily seeks to address questions related to the sustainability of facilitated processes and the effectiveness of capacity development methods to train facilitators and thus strengthen local facilitation.

This study investigated the impacts of organic- and clay-based soil amendments, and their combinations on crop water productivity (CWP) using maize as a test crop. On-station field trials were established over two consecutive years at the Naphok and Veunkham sites in Laos. At each site, 10 treatments were applied in a randomized complete block design with three replications. The treatments were control, rice husk biochar (10 t ha-1), bentonite clay (10 t ha-1), compost (4 t ha-1), clay-manure compost (10 t ha-1), rice husk biochar compost (10 t ha-1), bentonite clay + biochar, bentoniteclay + compost, biochar + compost, and bentonite clay + biochar + compost. All treatments were applied in 2011. Significant (p lt; 0.05) treatment effects in CWP and growing period evapotranspiration were determined. At Naphok, differences between the amended and control plots in CWP varied between 0.1 and 0.6 kg m-3 in 2011 and from 0.1 to 0.4 kg m-3 in 2012, whereas differences at Veunkham varied between 0.3 and 1.0 kg m-3 in 2011 and from 0.05 to 0.29 kg m-3 in 2012. At both sites, CWP in 2012 was significantly lower than 2011. Our results illustrate that organic- and claybased soil amendments improve CWP, indicating that soil-based interventions could be suitable options for improving agricultural productivity.

Accessibility to abundant sources of high-quality water is integral to the production of safe and wholesome fresh produce. However, access to safe water is becoming increasingly difficult in many parts of the world, and this can lead to the production of fresh produce contaminated with pathogenic microorganisms, resulting in increased risk of human disease. Water, an important raw material in the fresh produce chain, is used in considerable amounts in many operations, including irrigation and application of pesticides and fertilizers, but also as a transport medium and for cooling and washing in postharvest practices. In several reported outbreaks related to uncooked fruit and vegetable products, water has been identified as a likely source of the outbreak. The present study, initiated by the ILSI Europe Emerging Microbiological Issues Task Force in collaboration with 8 other ILSI branches and support of WHO/FAO, was undertaken to review the status of, and provide suggestions for, consideration by different stakeholders on water and sanitation and its impact on food safety and public health. A limited number of guidelines and regulations on water quality for agricultural production are available, and many of them are still heavily based on microbial standards and (debated) parameters such as fecal coliforms. Data gaps have been identified with regard to baseline studies of microbial pathogens in water sources in many regions, the need for agreement on methods and microbial parameters to be used in assessing water quality, the fate of pathogens in water, and their transfer and persistence on irrigated/processed produce.

When flowing through Hyderabad, the capital of Telangana, India, the Musi River picks up (partially) treated and untreated sewage from the city. Downstream of the city, farmers use this water for the irrigation of rice and vegetables. Treatment of the river water before it is used for irrigation would address the resulting risks for health and the environment. To keep the costs and operational efforts low for the farmers, the use of constructed wetlands is viewed as a suitable option. Towards this end, the paper investigates the interests and perceptions of government stakeholders and farmers on the treatment of wastewater for irrigation and further explores the consumer willingness to pay a higher price for cleaner produced vegetables. Full cost recovery from farmers and consumers cannot be expected, if mass scale treatment of irrigation water is implemented. Instead, both consumers and farmers would expect that the government supports treatment of irrigation water. Most stakeholders associated with the government weigh health and environment so high, that these criteria outweigh cost concerns. They also support the banning of irrigation with polluted water. However, fining farmers for using untreated river water would penalize them for pollution caused by others. Therefore public funding of irrigation water treatment is recommended.

Municipal wastewater sludge has been used for fertiliser and biogas production for several decades. Chemical compounds such as iron and aluminium are common coagulants used in wastewater treatment plants to remove suspended solids, phosphorus and micro-organisms. This laboratory study explores whether ferric chloride (FeCl3 as PIX-111) or aluminium chloride (AlCl3 as PAX-18) flocculation could stimulate biogas production in wastewater sludge contaminated with Microthrix parvicella. In a fermentation process run in three replicates, cumulative methane production was in average about 25 % higher using the iron flocculated sludge than using the aluminium flocculated sludge; this difference was statistically significant (P.05) in the subsequent runs of the semi-continuous process. In all runs, the iron flocculated sludge produced less (P.05) hydrogen sulphide in the biogas than the aluminium flocculated sludge. The numbers of M. parvicella stayed at the similar levels throughout the process. It is concluded that biogas production is higher and more stable with iron coagulant in comparison with aluminium coagulant, presumably due to the reduced formation of hydrogen sulphide. Thus, iron coagulants seem to be better than aluminium coagulants to stimulate the methane production process. Both coagulants significantly suppressed multiplication of M. parvicella in the biogas reactor, i.e. they did not evoke foaming in this experiment.

To assess the current situation of municipal solid waste (MSW) composting opportunities and potential acceptance of nutrient enriched pelletized compost in Sri Lanka,two field surveys were conductednationwide and in Kurunegala (Northwestern) area, respectively. Due to the low nutrient content of MSW compost, it qualifies mostly as a conditioner of the soil’s physical properties. As a result the compost so far produced across the country has received limitedattention. The surveys indicated that if the nutrient levels are in­creased, 74% of the farmers surveyed are willing to use thecompost. The percentage willing to use compost was similar among farmers of the three most common crops; coconut, paddy and vegetables,ranging from 72 to 77%. Using the land use pattern, the crop cultivation databases and the willingness to use (WTU) results, the potential demand for compost was estimated.As per the results, in the urban context of Kaluthara,a 160% larger capacity plant (present input capacity 38 t/day)would be needed to satisfy market demand within a 10 km radiusof theplant. For the Attanagalla plant (present capacity 10 t/day) within a rural setting, all compost could be absorbed within 2 km.