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Use of human excreta as fertilizer is not a new concept. However, with the use of the modern water-flush toilet, human excreta becomes mixed with water and causes environmental pollution. To reemphasize the nutritional value of human urine in the field, a urine diversion toilet was constructed in a community school situated in Kavre, Nepal. The purpose of establishing the urine diversion toilet is to improve hygiene outcomes through promoting proper sanitation and transforming the school community’s regular practice and attitudes towards urine as a resource. To ensure effective implementation of the urine diversion toilets, intervention mapping was used as a guiding framework. The aim of this paper is to document how the urine diversion toilet was planned and implemented in the school and how the urine diversion toilet was connected with the curriculum to address concerns regarding water, sanitation, and hygiene with a focus on sustainability through intervention mapping. This study highlights the benefits of intervention mapping as a systematic and step-by-step process for the planning and implementation of the urine diversion toilet. This study also highlights the benefits of connecting urine diversion toilets with school gardening, and engaging with local government and other stakeholders about the value of the approach.

Prior measurements at bench scale revealed that waterless urinal cartridges containing oily sealant fluids are capable of partitioning pharmaceuticals from urine and therefore reducing their concentration in wastewater. We sought to measure pharmaceutical removal from in-use waterless urinals. We developed a method to quantify pharmaceuticals in the sealant phase, which resulted in 79 ± 30% and 71 ± 30% recovery of eight pharmaceuticals from two sealant fluids, respectively. The method was applied to sealant samples collected over three weeks from in-use waterless urinals on a university campus. Six of eight pharmaceuticals were present in the sealant samples from 1.4 µg/L to 241 µg/L. Loads of the six pharmaceuticals detected in the sealants were removed from the receiving wastewater from 0.02 µg/day to 3.4 µg/day across the sampling period. The concentration of the pharmaceuticals were similar over time, indicating rapid saturation and washout of the sealant. We also observed relatively rapid loss of sealant at maintenance intervals consistent with the manufacturer's instructions. These findings indicate that while waterless urinals do remove some pharmaceuticals from the wastewater stream, meaningful changes to wastewater concentrations will only result if the sealant fluid and/or the urinal cartridge are significantly modified. PRACTITIONER POINTS: We developed a quantification method for pharmaceuticals in oily waterless urinal sealants. Pharmaceuticals were present at relatively low concentrations in the sealant phase of two in-use waterless urinals. We identify engineering challenges that must be overcome to meaningfully reduce pharmaceutical loads in wastewater with waterless urinals.

Because disease pandemics can accelerate rapidly in areas with limited clean-water access, a portable greywater reuse system may be useful to provide wash water at emergency health care units. In this study, a novel fed-batch (hybrid continuous-batch flow) net-zero water (NZW), or nearly closed-loop, reuse system comprising screening, 5 μm filter, and ozone-UV advanced oxidation was designed, constructed, and tested for performance with simulated and actual human showers. Water quality was tested for compliance with US drinking water standards, total organic carbon < 0.5 mg/L, and pathogen inactivation including 12 log(10) virus, 10 log(10) protozoa, and 9 log(10) bacteria as has been recommended for direct potable reuse. Energy, operation, and maintenance requirements were also evaluated, along with the system’s capacity to handle shock events such as unintentional contamination with urine. Design goals were achieved without the addition of GAC point-of-use filter, except compliance with bromate and nitrate drinking water standards, which were met only for temporary use of up to three years per person. A capacity of 32 showers/day at 1920 W continuous power is projected, without generation of potentially-infectious concentrate. To avoid the further increase in system weight and energy demand needed to address urine input, future integrated urine diversion and collection, and system drain-and-fill following detection of urine in recycled water by electrical conductivity, are suggested for the field unit. Field testing is recommended. Further research should focus on potential need for bromate/nitrate mitigation, and longer-term study of microbiological inactivation.

Resource recovery and emissions from sanitation systems are critical sustainability indicators for strategic urban sanitation planning. In this context, sanitation systems are the most often structured using technology-driven templates rather than performance-based sustainability indicators. In this work, we answer two questions: Firstly, can we estimate generic resource recovery and loss potentials and their uncertainties for a diverse and large set of sanitation systems? And secondly, can we identify technological aspects of sanitation systems that indicate a better overall resource recovery performance? The aim is to obtain information that can be used as an input into any strategic planning process and to help shape technology development and system design for resource recovery in the future. Starting from 41 technologies, which include novel and conventional options, we build 101,548 valid sanitation system configurations. For each system configuration we quantify phosphorus, nitrogen, total solids, and water flows and use that to calculate recovery potentials and losses to the environment, i.e. the soil, air, or surface water. The four substances cover different properties and serve as a proxy for nutrient, organics, energy, and water resources. For modelling the flows ex-ante, we use a novel approach to consider a large range of international literature and expert data considering uncertainties. Thus all results are generic and can therefore be used as input into any strategic planning process or to help guide future technology development. A detailed analysis of the results allows us to identify factors that influence recovery and losses. These factors include the type of source, the length of systems, and the level of containment in storage and treatment. The factors influencing recovery are related to interactions of different technologies in a system which shows the relevance of a modelling approach that allows to look at all possible system configurations systematically. Based on our analysis, we developed five recommendations for the optimization of resource recovery: (i) prioritize short systems that close the loop at the lowest possible level; (ii) separate waste streams as much as possible, because this allows for higher recovery potentials; (iii) use storage and treatment technologies that contain the products as much as possible, avoid leaching technologies (e.g. single pits) and technologies with high risk of volatilization (e.g. drying beds); (iv) design sinks to optimise recovery and avoid disposal sinks; and (v) combine various reuse options for different side streams (e.g. urine diversion systems that combine reuse of urine and production of biofuel from faeces).

A pot experiment was conducted at Arba Minch, Ethiopia to study the effects of urine on soil properties and yield of maize in natural settings. The pot treatments consisted of 500, 800, 1,000 and 1,200 ml of neat human urine collected from a UDDT (Urine Diversion Dry Toilet) added at different portions and control. The results showed that the response of the maize for most of the variables was very well expressed or significantly different at the application rate of 500 ml of urine; however, there was no significant difference between the 500 ml and the rest of the application. A significant increase in height, diameter, and length of leaf of maize was found in the urine treated soils. An improvement in soil phosphate chemical properties was noticed with increasing addition of urine; however, there was no significant increase in the ammonium nitrogen content and pH. The salinity of treated soil significantly increased at the bottom of the pot when compared with the control. In order to limit the increase in salinity of the soil and to get optimum maize growth in natural conditions, 500 ml urine addition per maize is recommended. The findings encourage the use of urine as fertilizer and a possible sink for UDDT waste.

The main objective of this paper is to review the literature on and compare the lifecycle costs of full sanitation chain systems in developing cities of Africa and Asia. Overall, financial cost reporting methodologies have been inconsistent and many studies only focus on capital costs or do not report cost data on desludging, transport and treatment. In addition, a comparative analysis of raw cost data across cities and countries would be of low utility, owing to the numerous determinants of costs (e.g. density, level of service) and their high sensitivity to local contexts. To circumvent this, this paper compares the cost ratios between different sanitation systems analysed in a same study. It concludes that conventional sewer systems are in most cases the most expensive sanitation options, followed, in order of cost, by sanitation systems comprising septic tanks, ventilated improved pit latrines (VIP), urine diversion dry toilets and pour-flush pit latrines. The cost of simplified sewer systems is found to be lower than both conventional sewer systems and septic tank-based systems, but lack of data prevented further comparisons with other types of sanitation solutions.

To address the shortcomings of modern wastewater treatment, Ecological Sanitation (EcoSan) has been advocated as a sustainable approach to promote closed-loop flows of resources and nutrients from sanitation to agriculture. In this study, we discuss the rationale behind its conception and provide a state-of-the-art review on the subject. Through an exhaustive literature analysis of EcoSan systems, its historical developments and programs implemented worldwide we (i) validate the potential applicability and feasibility of decentralized, source-based sanitation and (ii) depict fundamental problems in EcoSan systems design that have stalled its adoption and proliferation. Specifically, we focus on urine diversion to demonstrate its potential to elegantly separate, collect and concentrate products that we require (nutrients) and those that we wish to regulate (pathogens and micropollutants). Since recent research efforts have been devoted to the technological recovery of nutrients from human urine, we believe that we are witnessing a paradigm shift within a paradigm shift as it represents a change in emphasis from ‘split-stream collection and reuse’ to ‘split-stream collection, resource recovery and safe reuse’. Our analysis of various nutrient recovery technologies for human urine indicates that provisioning of urine-diverting toilets tends to reduce sanitary risks; however, to contain and completely eliminate these risks continued research effort is needed to envision and implement integrated technological pathways that ensure simultaneous nutrient recovery, pathogen inactivation and reduction of pharmaceuticals and active substances.

Fossa Alternas and double vault urine diverting dry (DVUDD) latrines have been extensively promoted as ecological sanitation (EcoSan) latrine options in Malawi, but little is known about whether they are used properly. A qualitative study of EcoSan users was conducted in Blantyre and Chikwawa districts, Malawi. Data were collected using in-depth interviews (IDIs). Twenty-eight (28) and seventeen (17) IDIs were conducted with household heads that had Fossa Alternas and DVUDD latrines, respectively. Recorded data were transcribed verbatim and analysed thematically. Of the total 45 EcoSan users, 40 had moderate to high knowledge on EcoSan latrine use, four had low knowledge and only one had no knowledge of how EcoSan latrines operate. Blockages of urine diversion systems, intensive management and maintenance needed for the latrines were reported as some problems related to the negative attitudes about EcoSan use. Use of soil and ash, urine diverting, use of hot water and chemicals to kill maggots, urinating in the drop-hole of the DVUDDs and poor maintenance of the roof were some of the practices reported on use of these latrines. It is therefore recommended that government, through community workers, should be monitoring practices on EcoSan latrine use and provide necessary support to users.

Urine ultrafiltration (UF) was studied in terms of flux, permeability, resistance and fouling. Two types of samples were used: stored urine representing the feedstock obtained from urine diversion dry toilets; and diluted stored urine representing the feedstock obtained from urinals. Three different filtration experiment sets were adopted in this study. For the first case, pressure was set in an ascending order, i.e. from 10 to 60 kPa during filtration of stored urine. For the second case, pressure was set in a descending order, i.e. from 60 to 10 kPa for the same feed stream. The third case involved filtration of diluted urine with pressure in ascending order, i.e. from 10 to 60 kPa. The results indicated that diluted urine had higher flux than undiluted urine with maximum values of 43 and 26 L·m−2·h−1 respectively. Cake formation was the dominating fouling mechanism during urine filtration with a contribution of about 90% to the total hydraulic resistance. The contribution of chemically irreversible fouling was low (−2%), unless operating from high to low pressures. Indeed, irreversible fouling appeared to be greater during the experiments starting at higher pressure. Although undiluted urine had a higher fouling potential compared to diluted urine, the specific cake resistance was higher for diluted urine, probably due to a denser cake caused by lower particle sizes in that sample. The permeate obtained after urine filtration had much lower suspended solids content compared to the feedstock, with rejections up to 99%. The concentration of the ionic species remained unchanged, and 75% of the organic compounds and dissolved solids remained in the permeate. Urine UF could then be used as pre-treatment to remove suspended solids.

A multiple criteria decision analysis (MCDA) was developed for the selection of sanitation systems. This decision support system was aimed at assisting municipal engineers to design and implement sustainable solutions to meet a municipality’s obligation to provide free basic sanitation (FBS). Multi-attribute value theory (MAVT) was selected as the method most suited to the problem under consideration. Criteria which determine the sustainability of sanitation were selected from the literature and a spreadsheet-based MCDA with stakeholder and expert user interfaces was developed. Stakeholders determine the weighting of each indicator and expert users determine the values to be entered for the alternatives against each indicator. The partial values are aggregated using a weighted sum function. Research carried out into the implementation of FBS by the eThekwini Municipality that includes the city of Durban was analysed. This informed the allocation of indicator values to the sanitation alternatives under consideration: ventilated improved pit latrines (VIPs) and urine diversion dehydrating toilets (UDDTs). An innovative scenario analysis method was used to determine the effect of different weightings and/or values, representing changes in stakeholder involvement, resource recovery and political support for ecological sanitation. The MCDA was found to provide a guiding framework for municipal engineers in their efforts to implement sustainable sanitation. The process of deriving values for the MCDA is likely to prove even more useful than the overall value scores of the options under consideration. Keywords : VIP ventilated pit latrine, UDDT urine diverting dry toilet, sustainability, eThekwini

ECOSAN is a recent domestic wastewater management concept which suggests segregation at the source. One of these streams, yellow water (human urine) has the potential to be used as fertilizer, directly or indirectly, because of its rich content of plant nutrients. One physicochemical method for indirect use is adsorption/ion exchange using clinoptilolite. This paper aims to present the results of a scenario focusing on possible diversion of urine and self-sufficiency of nutrients recovered on site through the use of this process, using actual demographic and territorial information from an existing summer housing site. Specifically, this paper aims to answer the questions: (i) how much nitrogen can be recovered to be used as fertilizer by diverting urine? and (ii) is this sufficient or in surplus within the model housing site? This sets an example of resource-oriented sanitation using stream segregation as a wastewater management strategy in a small community. Nitrogen was taken as the basis of calculations/predictions and the focus was placed on whether nitrogen is self-sufficient or in excess as fertilizer for use within the premises. The results reveal that the proposed application makes sense and that urine coming from the housing site is self-sufficient as fertilizer within the housing site itself.

The technologic resilience of water and wastewater service options was compared for a coastal community. Options included a centralized, conventional system; decentralized wastewater options such as composting and urine diversion toilets paired with a centralized drinking water system; and centralized drinking water with on-site graywater and rainwater reuse along with a centralized blackwater pressure sewer and digester. Four characteristics of resilience were reviewed based on literature for each option: the robustness, adaptive capacity, rapidity, and resourcefulness. Each system was evaluated for a cold weather event, storm event, power outage, short-term drought, wildfire, and predicted climate changes. Across all events, the service options utilizing graywater reuse and a blackwater pressure sewer and digester were considered the most robust. This was due to the potential advantages of water savings during drought and less environmental contamination during storms, assuming the addition of a backup generator at the household level; however, responsible management of the on-site components of these systems was important for resourcefulness. A scenario with multiple storm, wildfire, and drought events was constructed to quantitatively compare the resilience of the options with respect to water and wastewater service over a 100-year service life. Overall, no one system was the clear resilient choice given the selected events and assumptions, and resilience based on past event frequency over-predicted performance compared to the projected frequency given climate change. Key uncertainties include the duration of event failure, the frequency of future events, and the possible impact of water saving technology on the availability of source water.

Bangladesh has made a significant contribution to supply improved sanitation facilities in rural areas in recent years. As it is the most known option, pit latrines were the most favourable technology. Yet, as Bangladesh is a country of flooding and high groundwater table, pit latrines not only flush out and cause pollution; they also become inaccessible during floods, and remain filled with silt after the floods. Every year floods destroy many sanitation facilities and force people to resort to open defecation, despite the capital-intensive investment. Urine Diversion Dehydration Toilets (UDDTs) were evaluated on their suitability in flood-prone areas and their affordability in the context of Bangladesh. A survey conducted in two flood-prone areas of Bangladesh showed that with an average height of 0.69 m the UDDTs are higher than the average highest flood level of 0.31 m. To decrease cost and construction complexity, a local design was developed based on the current pit latrine, at 50% of the costs of the current UDDTs. Although the resulting cost is still not within reach for most Bangladeshi, the affordability could be increased by taking into account avoided emptying costs as well as the added value of human excreta as a fertilizer.

‘Lessons learnt on Ecosan in Morocco’ is a short analysis of experience gained in Morocco especially in rural areas where people do not have adequate systems of evacuation of their wastewater. The rural population cannot afford conventional sanitation systems. In response to this, we have thought to promote ecological sanitation that recognises wastewater not as a waste but as a resource. The first Urine-Diversion Dehydration Toilets (UDDTs) were introduced in a rural village called ‘Dayet Ifrah’ in Morocco in December 2009. Since then, households are starting to see the advantages of UDDTs and the systems are becoming more and more accepted. The UDDT systems implemented in the village could be used as a model for Moroccan rural areas. This paper sets out how the Ecosan approach was successfully introduced in Morocco where people are motivated by reasons to improve this approach such as no smell, safety, comfort, privacy and water reuse. Results reveal that the users are satisfied with the Ecosan approach to cleanse their wastewater. Although Ecosan is relatively new to Morocco, it seems that it can succeed in very poor populations. The paper contains information on general experiences in the different countries and also lessons learnt on Ecosan in each country.

A urine diversion dehydration toilet (UDDT) is a kind of toilet which can be used to recover resources such as nutrients and can also be an option to improve the sanitary situation in low income countries. A structured questionnaire survey, key informant interviews, participatory approaches such as focus group discussion (FGD) and mass gathering were carried out in Kenya to assess social acceptance and scope of scaling up of UDDTs. The results showed that almost all respondents among UDDT users and non-users have overcome social and cultural barriers to accept UDDTs. Most UDDT users were applying UDDT products as fertilizers on their farms. It is recommended to promote coordination and networking of local community based organizations in order to replicate UDDTs.

As recent emergencies have shown, there are still significant challenges in the timely provision of safe sanitation in natural disasters or conflict situations. In urban emergencies or areas where it is impossible to dig simple pit latrines because of high water tables, hard rock, or lack of permission, it takes agencies considerable time to construct elevated latrines or alternative designs such as urine diversion toilets. This paper describes the challenges often faced in the rapid construction of latrines in emergencies and then looks at a number of case studies, from the Haiti earthquake and the 2010 floods in the Philippines, of how these obstacles were overcome. It also documents some of the recent innovations and improvements suppliers have made in increasing the scope of their emergency sanitation equipment.

Proper excreta management in flood- and cyclone-prone areas of Bangladesh is a challenge. The appropriateness of latrine technology depends on groundwater table, geographical context and acceptance by the community. Field trials by Oxfam GB found that raised pit latrines are more appropriate in flood- and cyclone-prone areas, and more widely accepted by the community, than other technologies. In addition, urine diversion and Ecosan latrines were also felt to be appropriate and acceptable in certain contexts. To reduce the risk to health, a pump was promoted, instead of manual desludging of latrine pits, and met with a favourable response from the community and sweepers.

Material Flow Analysis is a method that can be used to assess sanitation systems with regard to their environmental impacts. Modelling water and nutrients flows of the urban water, wastewater and waste system can highlight risks for environmental pollution and can help evaluating the potential for linking sanitation with resource recovery and agricultural production. This study presents the results of an analysis of nitrogen and phosphorus flows of Arba Minch town in South Ethiopia. The current situation is modelled and possible scenarios for upgrading the town's sanitation system are assessed. Two different scenarios for nutrient recovery are analysed. Scenario one includes co-composting municipal organic waste with faecal sludge from pit latrines and septic tanks as well as the use of compost in agriculture. The second scenario based on urine-diversion toilets includes application of urine as fertiliser and composting of faecal matter. In order to allow for variations in the rate of adoption, the model can simulate varying degrees of technology implementation. Thus, the impact of a step-wise or successive approach can be illustrated. The results show that significant amounts of plant nutrients can be provided by both options, co-composting and urine diversion.

The acceleration of sanitation delivery towards meeting the South African Government's target of completely eradicating the existing backlogs by 2010, has led to a surge of activities. As part of its strategy for ensuring that basic sanitation is provided, the policy has recommended that a ventilated improved pit latrine (VIP) is considered as the basic minimum requirement in the form of a sanitation technology. The up-scaling and delivering of sanitation in many cases in the form of VIPs and its derivatives, as well as urine diversion technology are beginning to pose many technical challenges. The principles on which they have been designed are not always being observed in practice. As a result, some systems are filling up much faster than expected. Research has found that the breakdown in the faeces is not happening as would be expected in an anaerobic reactor, and that the drying of faeces in humid conditions, even with the use of drying agents, is not optimum. These problems, which are being experienced in the field, will have long term repercussions on the sustainability of sanitation provision. This paper aims to share these experiences and findings of research, and the impact it may have on the Sanitation MDG goals.

This study collects experiences from existing systems with urine diversion and dry handling of faecal matter and presents design recommendations for improved function of new systems. Urine collection and piping systems were studied in four large residential areas in Scandinavia and South Africa where urine had been collected separately for 5–9 years and dry faeces collected for 4–15 years. We found that larger (>1 toilet) urine collection systems should have odour traps. Blockages in u-bend odour traps can be efficiently prevented by cleaning the u-bend 1–4 times per year with a sewage auger, caustic soda solution or strong acetic acid. A urine pipe diameter of 75 mm and a gradient of at least 1% are recommended. In small systems without a u-bend, a diameter of 25 mm can be used in combination with a gradient of at least 4%. For faecal collection, the most important factors for good function and high acceptability of the system are diversion of the urine, small collection bins (high emptying frequency) and easy access for emptying of bins.

Simple models based on the physical and biochemical processes occurring in septic tanks, pit and urine diversion latrines were developed to determine the nutrient flows in these systems. Nitrogen and phosphorus separation in different output materials from these on-site sanitation installations were thus determined. Moreover, nutrient separation in septic tanks was also assessed through literature values and by eliciting expert judgement. Use of formal expert elicitation technique proved to be effective, particularly in the context of developing countries where data is often scarce but expert judgement readily available. In Vietnam, only 5–14% and 11–27% of the nitrogen and phosphorus input, respectively, are removed from septic tanks with the faecal sludge. The remaining fraction leaves the tank via the liquid effluent. Unlike septic tanks, urine diversion latrines allow to immobilise most of the nutrients either in form of stored urine or dehydrated faecal matter. These latrines thus contribute to reducing the nutrient load in the environment and lowering consumption of energy and non-renewable resources for fertiliser production.

By 2010 Africa's urban population will have grown to over 420 million with on-site sanitation the predominant excreta disposal option. The use of on-site sanitation has important public health benefits but can result in large faecally derived loadings of nitrogen and chloride to groundwater resources. Nitrate is of particular concern, with elevated concentrations linked to potentially serious health problems. N and Cl can derive from natural sources so it is important to quantify the additional impact of human activities. Several authors have used empirical relationships between nitrate and chloride concentrations to assess the extent to which excreta influences groundwater quality. However, these relationships have assumed fixed loadings from excreta. Relationships between N and Cl have been extended here by adding country-specific estimates of average annual per capita nitrogen and chloride content of, and loading from, excreta. The results are compared with groundwater monitoring results from two very different mid-sized African cities (Timbuktu, Mali and Lichinga, Mozambique) where the vast majority of residents use on-site sanitation and are dependent on the subsurface water for drinking purposes. The results illustrate the impact of urbanisation on groundwater quality. They are compared with data from other African cities to allow the calculation of a general nitrate and chloride relationship for unsewered African urban areas. Potential interventions to help arrest rising nitrate levels and so provide a public health benefit are also examined.

In the present study we attempted to develop a reactor system to recover phosphorus by struvite precipitation, and which can be installed anywhere in the field without access to a laboratory. A reactor was developed that can run fully automated and recover up to 93% of total phosphorus (total P). Turbidity and conductivity signals were investigated as automation proxies for magnesium dosage, thus making laboratory phosphate measurements to determine the exact magnesium dosage unnecessary. Conductivity is highly influenced by the dosing parameters (molarity and pump speed) and turbidity is affected by particle size distribution issues. Algorithms based on both conductivity and turbidity signals were not able to detect the precipitation endpoint in real time. However it proved possible to identify the endpoint retrospectively from the conductivity signal, and thereafter to dose an algorithm-calculated volume of urine to use up the excess magnesium dosed.Keywords: struvite precipitation, human urine, turbidity, conductivity, automation, magnesium dose, VUNA

Sanitizing human excreta with nutrient recovery is a crucial issue especially for peri-urban and rural areas of developing countries. In addition to human excreta, the sanitary concerns of livestock excreta are recently growing due to control the domestic-animal-related diseases such as bird flu. In order to address those problems, this study examines the vacuum truck-collection system combined with urine-faeces diversion for peri-urban and rural areas. In the system, the diverted faeces and livestock excreta are fermented, and urine is directly used and/or phosphorus in urine is recovered by struvite formation. Firstly, each treatment and recovery is examined from the technological aspects. Secondly, the methane and struvite production in the system is calculated. As a result, the fermentation was considered to proceeds easily compared to traditional mixed excreta fermentations, and nutrient in urine could be easily recovered in the system. In addition, the system produces methane of 1,107 Nm3-CH4 per day, struvite of 51.9 ton-P2O5 per year for a population of 100,000 with 5,000 pigs and 20,000 chickens.

Interest in phosphorus recovery from urine diverted from faeces has been growing recently. Phosphorus in urine can be precipitated out as struvite (MgNH4PO4•6H2O) with addition of magnesium salt under alkaline conditions. Struvite formation, however, should be more well understood for its practical application. We predicted the struvite formation with a development of a new equilibrium model. The model considered the formation of eight different kinds of precipitates, including struvite, with effects of ionic strength and temperature. In addition, experiments on struvite formation in urine were conducted for the model validation. The model prediction of struvite formation had good agreement with the experimental results. The optimum pH to form struvite was predicted to be 9.4–9.7. In order to precipitate 99% of phosphate in urine with 1.5 fold Mg concentration to PO4-P, the pH value was necessary to be more than 8.1 based on the model prediction.

This paper discusses a urine diversion (UD) trial implemented within the institutional setting of the University of Technology Sydney that sought to identify key issues for public UD and reuse systems at scale in the Australian urban context. The trial was novel in its transdisciplinary action research approach, that included consideration of urine diverting toilets (UDTs) as socio-technical systems where interactions between users' practices and perceptions and the performance of the technology were explored. While the study explored a broad range of issues that included urine transport, reuse, and regulations, amongst others, the boundary of the work presented in this paper is the practicalities of UD practice within public urban buildings. Urine volume per urinal use, an important metric for sizing tanks for collecting urine from waterless urinal systems in commercial buildings, was also estimated. The project concluded that current UDTs are unsuitable to public/commercial spaces, but waterless urinals have a key role. © IWA Publishing 2013.

Drinking water quality was investigated at source and corresponding point-of-use in 2 peri-urban areas receiving drinking water either by communal water tanker or by delivery directly from the distribution system to household-based groundtanks with taps. Water quality variables measured were heterotrophic bacteria, total coliforms, E. coli , conductivity, turbidity, pH, and total and residual chlorine. Water quality data were analysed together with an existing epidemiological database to investigate links between microbial quality of drinking water, household demographics, health outcomes, socio-economic status, hygiene and sanitation practices. Groundtank households had better quality drinking water than households using storage containers filled from communal tankers. Uncovered storage containers had the poorest microbial water quality among all storage containers. All stored water did not meet drinking water standards, although mains water did. Households with children under 5 years and using open-topped containers had the poorest water quality overall. Households with groundtanks had the best water quality at point-of-use, but did not have the lowest occurrence of health effects. Although groundtanks were supplied together with urine diversion (UD) toilets and hygiene education, groundtank households showed overall poorer hygiene practices than tanker-supplied households, and some groundtank households with UD toilets preferred to continue using open defecation. Households that practised open defecation had higher levels of E. coli in their drinking water and higher rates of adverse health outcomes. Poorer socio-economic standing and lower educational standard were associated with poorer water quality, poorer hygiene practices and higher rates of diarrhoea and vomiting. Keywords: drinking water; point of use; water quality; water quantity; hygiene; sanitation

A novel ammonia stripping method, including a CO2 pre-stripper was used to treat a mix of supernatant liquor from an anaerobic digester and urine in order to recycle nitrogen as ammonium sulfate at full-scale in the WWTP Kloten/Opfikon. Waste streams were not generated, since the ammonia was recovered as a marketable nitrogen fertilizer, turning a waste product into a valuable product. The efficiency of this system was increased by means of the addition of pre-treated urine collected separately at EAWAG building. The separation step was performed by the use of water free urinals and urine diversion flush toilets. An increase of 10% in the liquid flux with the addition of the urine translated into a 40% increase of the ammonia concentration in the inlet of the stripping unit. The achievement of these percentages generated a proportional increase in the fertilizer production. The urine pre-treatment was carried out by adding magnesium to produce a precipitate of struvite. The first experiments with the combined treatment showed the feasibility of the combination of the separation and pre-treatment steps., Water, 5 (3), ISSN:2073-4441

The current environmental challenges that most middle- and low-income countries have been experiencing has led to new environmentally sustainable and economically viable sanitation solutions, such as waterless systems with source separation of human waste. We conducted a cross-sectional study in eThekwini municipality to explore the post-implementation challenges of urine diversion dehydration toilets (UDDTs) after a decade of installation and the adaptive processes necessary to increase the sustained use of the toilets. A structured questionnaire was administered to 17 499 households in 65 rural and per-urban areas of eThekwini using mobile phone technology. Results report low levels of satisfaction with the facilities as well as an association between perceived smell in the toilets and malfunctioning of the pedestal, and low use of UDDTs when a pit latrine is present in the dwelling perimeter. Conclusions relate to the importance of educational and promotional activities that stress the economic return derived from reusing urine and excreta in agricultural activities.Keywords: Sanitation, urine diversion toilets, user satisfaction, South Africa

Ecological sanitation is a system that, unlike the traditional waterborne sewerage and pit toilet systems, regards human excreta as a resource to be recycled rather than as a waste. There is, however, little or no information on the fertiliser value of human excreta in South Africa. This study, therefore, evaluated the effectiveness of human manure as a source of nutrients using cabbage as a test crop at Ntselamanzi location, Alice, South Africa as part of a project intended to generate knowledge and good practice in ecological sanitation. Treatments were arranged in a randomised complete block design with 4 replications and consisted of a control, 100 kg N·ha-1 as goat manure, and 4 non-zero rates of human manure and NPK fertiliser applied to supply the equivalent of 50, 100, 200, and 400 kg N·ha-1. Human manure resulted in higher cabbage yields than goat manure but was out-yielded by inorganic fertiliser. The greater effectiveness of human manure when compared with goat manure was attributed to the fact that it was a better source of K and P for plants as it maintained higher levels of these nutrients in soil than goat manure. For greater agronomic effectiveness, the human manure should be co-applied with some inorganic N fertiliser as it proved to be a poor source of nitrogen. The human manure increased soil pH and therefore has potential for improving crop growth in acidic soils through its liming effects as well. The dry human manure was evaluated as comparable to Type B sludge in South Africa with respect to microbial content and could therefore be used to fertilise some crops/plants provided stipulated restrictions to minimise human exposure are adhered to.

In the main office building of GTZ in Eschborn, Germany a resource-oriented sanitation system containing urine diversion (UD) toilets and waterless urinals has been in operation since 2006. After 2.5 years of operating the system, a first overall evaluation of the system in terms of its acceptance amongst the users and the cleaning staff was conducted by carrying out two surveys and many interviews. The overall result is that most of the users appreciate the sanitation concept in theory but have problems with the technical design of the particular type of UD flush toilets installed here. The survey results also gave some directions towards which hygiene devices the users would appreciate in order to overcome their reluctance to sit down on the toilet seat in public buildings (the sitting being necessary for correct operation of the urine valve to separate urine from flush water). Also, it is difficult to convince the cleaning and facility maintenance staff of the necessity of special cleaning and preventative maintenance routines. Hence, before such systems can be widely used, clear cleaning routines and maintenance instruction are required as well as certain technical modifications of this type of UD flush toilets to optimise the urine/water separation and the flushing properties of the toilet.

Tuberculosis is a zoonotic disease that mainly causes respiratory infection. However, it can also infect other organs such as the kidneys and bladder, which can lead to high counts of the organisms in the urine. Introducing urine diversion systems and reuse of the urine in agriculture may introduce new transmission routes for infection, increasing the risk of spread. This study evaluated the inactivation rate of mycobacteria in human urine for ensuring safe reuse in agriculture and examined whether current World Health Organization recommendations on storage time are sufficient for inactivating Mycobacterium tuberculosis and Mycobacterium bovis. In this study, a decimal reduction in M. tuberculosis and M. bovis in human urine containing 7 and 3 g NH3-N L−1, respectively, was obtained in just over 10 days at 4°C and below three days at 22°C. This is considerably faster than previously reported reduction rates of mycobacteria in animal slurry at similar temperatures. Based on the present results, a storage time of five weeks at temperatures below 20°C or of two weeks at temperatures above 20°C is sufficient to prevent transmission of mycobacteria when recycling human urine. These values lie within the WHO recommended storage period.

Northern Vietnam has a history of using urine diversion (i.e., UD) toilets with agricultural use of excreta. This study tried to identify the current practices of UD toilets in suburban Hanoi, Vietnam. An interview survey to 120 households showed that UD toilets were used by 26.7% of households, of which most were double-vault UD toilets. Human wastes were used by 73.0% of vault toilets. It was interpreted that they are still recognized as not wastes but fertilizers especially by farming households in recent sub-urban Hanoi. Double-vaults UD toilets were used in significantly old houses compared to flush toilets with p

The recent discovery of the bio-waste and excreta treatment of a former civilisation in the Amazon reveals the possibility of a highly efficient and simple sanitation system. With the end product that was black soil they converted 10% of former infertile soil of the region: Terra Preta do Indio (black soil of the Indians). These soils are still very fertile 500 years after this civilisation had disappeared. Deriving from these concepts, Terra Preta Sanitation (TPS) has been re-developed and adopted. TPS includes urine diversion, addition of a charcoal mixture and is based on lactic-acid-fermentation with subsequent vermicomposting. No water, ventilation or external energy is required. Natural formation processes are employed to transform excreta into lasting fertile soil that can be utilised in urban agriculture. The authors studied the lacto-fermentation of faecal matter with a minimum of 4 weeks followed by vermicomposting. The results showed that lactic-acid fermentation with addition of a charcoal mixture is a suitable option for dry toilets as the container can be closed after usage. Hardly any odour occured even after periods of several weeks. Lactic-acid fermentation alone without addition of bulking agents such as paper and sliced-cut wood to raise the C/N ratio is creating a substrate that is not accepted by worms.

Pook se Bos informal settlement and the Cape Town Water & Sanitation Services Department are partnering on an urban sanitation project with a Dutch Consortium consisting of Lettinga Associates Foundation (LeAF), Landustrie Sneek and Vitens-Evides International. The aim of the project is to improve the basic sanitation services provided in informal settlements through the implementation of the MobiSan approach. The approach consists of a communal Urine-Diversion and Dehydration Toilet (UDDT) built in a former sea shipping container. The system is independent of water, electricity or sewerage connection and it is maintained by full-time community caretakers who also act as hygiene promoters. The project seeks to link sanitation services with hygiene promotion in informal settlements while enhancing user satisfaction and reducing costs in providing basic sanitation services. This paper describes the preliminary experiences and lessons learnt during the implementation and evaluation of the MobiSan prototype and discusses its potential for replication. The MobiSan has proved to be an appropriate option by means of dealing successfully with shallow groundwater table, land availability and high settlement densities. In addition it has been demonstrated to be cost-competitive in terms of operating cost compared to chemical toilets.

The most advantageous approach to pathogen destruction in a urine-diversion toilet vault is to maximize the effects of various environmental factors (i.e., pH, temperature, moisture content, type of bulking agent, and storage time). To quantify these effects, a field experiment was set up, consisting of 6 urine-diversion toilet vaults, each with a different combination of feces and bulking agent (soil, ash, wood shavings, sodium hydroxide, or straw) and ventilation (ventpipe/no ventpipe). The pH of the mixes varied from 6.37 to 10.09. Temperature probes, which were connected to a data logger, were inserted to the heaps, and the logger monitored over a period of nearly 10 months. Mean heap temperatures ranged from 16.8 degrees C in winter to 27.6 degrees C in summer. In addition, samples were taken at intervals from the various heaps in the vaults and also from an open heap exposed to the elements. The samples were subjected to microbiological testing to quantify the pathogen dieoff over time. In the vaults, there was a 3log10 (99.9%) reduction of total coliform between 130 and 250 days, fecal coliform between 100 and 250 days, and fecal streptococci from 125 days and longer. In the open heap, these times varied, from 115 days for both total and fecal coliform, to 140 days for fecal streptococci. Viable Ascaris ova were reduced to zero between 44 and 174 days in the vaults and by 44 days in the open heap. The results of this research showed that ventilation of the vault by means of a ventpipe does not result in any meaningful difference in the vault temperature or the rate of pathogen dieoff. While the type of bulking agent used does not significantly affect the temperature of the heap, it does have an effect on the rate of pathogen dieoff. The ordinary soil mix was seen to give the best results, and this was ascribed to the effect of competing microorganisms in the soil itself. It is concluded that, for safety, vaults of urine-diversion toilets should be sized for a storage period of 9 to 12 months from the last use.

This paper describes the potential of ecological sanitation (ecosan) to provide sustainable excreta disposal in emergency situations and in peri-urban areas or slums in developing countries. At the present time, pit latrines are the most common form of excreta disposal both for emergency situations and in low-income peri-urban areas or slums. Although not intended to be a long-term solution, pit latrines provided during emergencies are often used for a long time (more than six months to years). This practice is not sustainable if the area is prone to flooding or there are soil conditions that allow groundwater pollution in areas where groundwater is used for drinking water, to name but two of the main factors. We propose eight criteria for the applicability of ecosan based on analysis of three case studies representing different types of emergency situations. The two most important criteria are awareness and expertise in ecosan within the aid agencies, and availability of standardised, lightweight toilet units that are quick to assemble and easy to transport (e.g. container for faeces, and urine diversion squatting pan made of impact-resistant molded polypropylene). Such toilets could be moved to, or replicated in, other areas in need after the emergency (peri-urban areas or slums). This would provide benefits for Millennium Development Goals achievements (targets on hunger, child mortality, sanitation and slum dwellers) at lower cost than conventional sanitation systems. Costs for sanitation systems should be compared based on the entire system (toilet, transport, treatment, reuse in agriculture), using Net Present Value analysis for capital, and operating and maintenance costs.

The pre-selection of locally appropriate sanitation technologies and systems is crucial for strategic sanitation planning as any decision is only as good as the options presented. One approach that allows us to systematically consider the local conditions and a diverse range of conventional and novel technologies and systems is the Santiago method. In this paper, we discuss whether the Santiago method can be applied to the case of Latin America and what we would gain from this application. We do so by expanding the Santiago technology library with technologies that have been shown to be promising in metropolitan areas of Latin America, such as condominial sewer, container-based sanitation, and activated sludge. We then apply Santiago to the semi-informal settlement Quebrada Verde (QV) in Lima, Peru. Using Santiago, we were able to generate 265,185 sanitation system options from 42 technologies and 18 appropriateness criteria. A set of 17 appropriate and divers are then selected. The diversity is defined by 17 system templates. To further evaluate these 17 systems, resource recovery and loss potentials are quantified. Higher nutrients (nitrogen and phosphorus) and total solids recovery are observed for systems that combine urine diversion and biofuel production. The case of QV shows that the Santiago method is applicable in the Latin American context.

This study was part of the VUNA project aimed to develop an affordable sanitation system that produces a valuable fertiliser, reduces pollution of water resources and promotes health. Urine diversion dry toilets (UDDTs) simplify the on-site hygienisation of faeces and allow for nutrient recovery from urine. Social acceptance is vital for the implementation of the UDDT, because sanitation is only effective if the system not only provides a well-designed toilet and effective waste management, but also offers users a facility that caters to their needs and is sensitive to their cultural lifestyle. This study used qualitative and quantitative methods to investigate acceptance, use and maintenance of UDDTs. Key findings indicate lower levels of acceptance of UDDTs among the elderly, who are accustomed to traditional pit toilets. The users aspire to own a flush toilet, perceived to be indicative of household wealth. A dominant concern was emptying the pit and the quality of the building material. Community interventions are required that will promote acceptance, understanding and encourage proper use and maintenance of the UDDT, and may need some technology modification. There is an urgent need for increased community participation to address users' perceptions, attitudes and behaviour concerning the UDDT.

Over four billion people are discharging untreated human excreta into the environment without any prior treatment, causing eutrophication and spreading disease. The most nutrient rich fraction is the urine. Urine can be collected separately and dehydrated in an alkaline bed producing a nutrient rich fertiliser. However, faecal cross-contamination during the collection risks to introduce pathogens to the urine. The objective of this hygiene assessment was to study the inactivation of five microorganisms (Ascaris suum, Enterococcus faecalis, bacteriophages MS2 and ΦX 174 and Salmonella spp) in alkaline dehydrated urine. Fresh human urine was dehydrated in wood ash at 42 °C until the pH decreased to ≤10.5, at which point the saturated ash was inoculated with faeces containing the microorganisms and left open to the air (mimicking stockpiling of the end product) at temperatures of 20 and 42 °C. The bacteria and bacteriophages were inactivated to below the detection limit (100 cfu ml−1 for bacteria; 10 pfu mL−1 for bacteriophages) within four days storage at 20 °C. A. suum inactivation data was fitted to a non-linear regression model, which estimated a required 325 days of storage at 20 °C and 9.2 days at 42 °C to reach a 3 log10 reduction. However, the urine dehydration in itself achieved a concentration