A reminder of resources:
From the WHO website:
Household water treatment and safe storage
WASH in Schools SWASH+ website:
From Sanitation Updates:
Peepoo toilets in flood emergencies in Sindh, Pakistan and Kisumu, Kenya
Posted: 19 Sep 2012 08:02 AM PDT
Living without sanitary sewers in Latin America
Posted: 18 Sep 2012 02:09 PM PDT
Cash Rewards Spur Poor Communities to Pay for Sanitation Projects
Posted: 11 Sep 2012 10:22 AM PDT
WaterAid Australia – Towards Inclusive WASH: Sharing evidence and experience from the field.
Posted: 06 Sep 2012 06:11 AM PDT
A selection from email alerts:
• TROPICAL MEDICINE AND INTERNATIONAL HEALTH VOL 17; NUMB 9 (2012) pp.1133-1141
Hygiene and sanitation practices amongst residents of three long-term refugee camps in Thailand, Ethiopia and Kenya
Biran, A.; Schmidt, W. P.; Zeleke, L.; Emukule, H.; Khay, H.; Parker, J.; Peprah, D.
Abstract Objective- To further the understanding of sanitation and hygiene in long-term camp populations. Methods- Data were collected by structured observation of handwashing (126 households), a questionnaire on sanitation, hygiene and household characteristics (1089 households) and discussions with mothers. Random walk algorithms were used to select households for observation and survey. Respondents for qualitative methods were a convenience sample. Results- Across all key handwash occasions [excluding events with no handwash (n-=-275)], soap was used for 30% of handwashes. After latrine use, both hands were washed with soap on 20% of occasions observed. Availability of soap in households differed across sites and mirrored the extent to which it was distributed free of charge. Qualitative data suggested lack of free soap as a barrier to -safe- handwashing. Laundry was the priority for soap. In Ethiopia and Kenya, open defecation was practised by a significant minority and was more prevalent amongst households of rural origin. In Ethiopia, open defecation was significantly more prevalent amongst women. Conclusions- Despite continuing hygiene education, rates of -safe- handwashing are sub-optimal. Soap scarcity in some households and the prioritisation of laundry are barriers to safe practice. Heterogeneity with respect to education and place of origin may need to be taken into account in the design of improved interventions.
PROCEEDINGS- INSTITUTION OF CIVIL ENGINEERS MUNICIPAL ENGINEER
VOL 165; ISSU 3 (2012)
(WEDC-authored papers in red)
Editorial: Diversity and inclusion
The Equality and Diversity Panel, Institution of Civil Engineers
Diversity training for engineers: making `gender’ relevant
Reed, B.; Coates, S.
An analysis of gender when creating a water engineering course
`With’ and not `to’ – the key to unlocking communities
Improving public services through open data: public toilets
Bichard, J.-A.; Knight, G.
Water and sanitation for all in low-income countries
Jones, H.; Fisher, J.; Reed, R.
Engineering to reduce crime and disorder in public places
Gilbertson, A.; Hayes, A.
WATER SCIENCE AND TECHNOLOGY
VOL 66; NUMB 6 (2012)
The situation of sanitary systems in rural areas in the Miyun catchment, China
Kroger, C.; Xu, A.; Duan, S.; Zhang, B.; Eckstadt, H.; Meissner, R.
The Miyun Reservoir provides most of Beijings drinking water. Despite its importance, the Miyun reservoir suffers from decreasing water quality caused by uncontrolled wastewater discharges, inadequate land use and over fertilization, which increase the pressure on soil and water resources. The major pollutants are nitrogen and phosphorus which emanate to some extent from untreated sewage. So far there is little data about the existing wastewater quantity and quality in rural settlements in northern China. This study was conducted in typical villages situated along upstream rivers in the catchment of the Miyun Reservoir. The main objective was to determine the current situation and efficiency of the wastewater treatment system in rural settlements.
Impact of the surface characteristics of rainwater tank material on biofilm development
Kim, M.; Ravault, J.; Han, M.; Kim, K.
In order to determine the impact of rainwater construction material on the development of a biofilm, three materials were tested: concrete, clay, and PVC. The biofilm attachment was initially more effective on clay coupons, but, after a period of three days, concrete coupons produced a greater quantity of biofilm than clay and PVC, in that order. The heterotrophic plate count in the rainwater indicated that this quantity tended to first increase following a rainfall, and then decrease. The new materials seemed to attach themselves to the existing biofilm on the wall and/or sediment in the form of small particles. The presence of fecal coliforms in the biofilm coupons was noted after major rainfall events, and this was correlated with the increase in fecal coliforms in the water. This study concluded that the most favorable support for biofilm development is concrete, clay, and PVC, in that order.
Potentials and limits of anaerobic digestion of sewage sludge: Energy self-sufficient municipal wastewater treatment plant?
Jenicek, P.; Bartacek, J.; Kutil, J.; Zabranska, J.; Dohanyos, M.
Anaerobic digestion is the only energy-positive technology widely used in wastewater treatment. Full-scale data prove that the anaerobic digestion of sewage sludge can produce biogas that covers a substantial amount of the energy consumption of a wastewater treatment plant (WWTP). In this paper, we discuss possibilities for improving the digestion efficiency and biogas production from sewage sludge. Typical specific energy consumptions of municipal WWTPs per population equivalent are compared with the potential specific production of biogas to find the required/optimal digestion efficiency. Examples of technological measures to achieve such efficiency are presented. Our findings show that even a municipal WWTP with secondary biological treatment located in a moderate climate can come close to energy self-sufficiency. However, they also show that such self-sufficiency is dependent on: (i) the strict optimization of the total energy consumption of the plant, and (ii) an increase in the specific biogas production from sewage sludge to values around 600 L per kg of supplied volatile solids.
Appropriate maximum holding times for analysis of total suspended solids concentration in water samples taken from open-channel waterways
Oudyn, F.W.; Lyons, D.J.; Pringle, M.J.
Many scientific laboratories follow, as standard practice, a relatively short maximum holding time (within 7 days) for the analysis of total suspended solids (TSS) in environmental water samples. In this study we have subsampled from bulk water samples stored at 4 C in the dark, then analysed for TSS at time intervals up to 105 days after collection. The nonsignificant differences in TSS results observed over time demonstrates that storage at 4 C in the dark is an effective method of preserving samples for TSS analysis, far past the 7-day standard practice. Extending the maximum holding time will ease the pressure on sample collectors and laboratory staff who until now have had to determine TSS within an impractically short period.
Journal of Water, Sanitation and Hygiene for Development
Volume 2 Number 3 (2012)
Removal of cyanobacteria by slow sand filtration for drinking water
Silvano Porto Pereira, Fabiana de Cerqueira Martins, Lenora Nunes Ludolf Gomes, Manoel do Vale Sales and Valter Lúcio De Pádua………. 133–145
Potential problems arising from the presence of cyanobacteria in water intended for human consumption have been reported by several researchers. Regarding water treatment plants, intact cells of cyanobacteria should be removed to avoid the release of cyanotoxins due to cell lysis. Water treatment techniques with different degrees of complexity can be employed but, whenever possible, the method of easiest installation, operation and maintenance should be selected, especially for non-industrialized countries and rural communities. In this context, research was carried out to evaluate the efficiency of slow sand filtration to treat water from Gavião reservoir in the city of Pacatuba, Ceara, Brazil, which has exhibited phytoplankton density of approximately 105 cells/mL with a prevalence of cyanobacteria representing over 90% of total cells. The results have demonstrated that slow sand filtration can be used to achieve water purification that meets federal standards. However, it was established that filtration through beds of gravel (prefilter) before the slow sand filtration is essential. The removal of phytoplankton reached values of approximately 97% and the filter run duration was more than 70 days. Furthermore, the slow sand filter was very efficient in removing total coliforms, with removal of up to 99.98%.
Cross-contamination of distributed drinking water as the cause of waterborne outbreaks in Armenia 1992–2010
Emma Anakhasyan, Christoph Hoeser, Thor Axel Stenström and Thomas Kistemann………. 146–156
Investigations and established causal relationship of waterborne outbreaks (WOs) from developing countries and countries in transition are sparse and mainly centered on agents, such as from Vibrio cholera and Shigella dysenteriae. Information, however, prevails in countries like Armenia with an epidemiological system in place. Groundwater is the main drinking water source (96%); water is delivered intermittently 12–14 hours per day. In 2005 about 7% of all infant deaths were attributed to intestinal infectious diseases. Recorded information on WOs and supply systems (1992–2010) was obtained from published official sources, from ‘gray-literature reports’, primary data collection from statistical records and through personal communication. Epidemiological descriptive analysis was made and Geographical Information System (GIS) applied for results visualization. In-depth outbreak analysis was conducted on selected cases. Overall, 104 WOs caused by different etiological agents were revealed. The main drinking water source in areas where outbreaks occurred was the centralized water supplies (69.2%) based on GIS mapping. The major cause of outbreaks was the cross-contamination of drinking-water distribution by wastewater. In Armenia the main areas to be addressed for the future are: service quality, source protection, delivery interruption and subsequent microbial contamination.
User perceptions of participatory planning in urban environmental sanitation
Christoph Lüthi and Silvie Kraemer………. 157–167
This paper aims to contribute to the growing body of literature on evaluation of community participation in the water and sanitation sector. The first part discusses the conceptual underpinnings of participatory approaches. The paper then analyses stakeholder perceptions about the Household-centred Environmental Sanitation (HCES) approach, a participatory planning approach recently validated in two countries: Lao People’s Democratic Republic (PDR) and Nepal. Post intervention surveys were conducted with experts and key informants in both countries to assess satisfaction regarding degree of participation, effectiveness of planning outcomes and process efficiency of the participatory planning process. It specifically looks at the variability in people’s perceptions about the costs and benefits of community participation. Empirical findings show that experts and participants show high satisfaction rates regarding involvement in decision making. The earlier and stronger residents were involved in the process, the higher the satisfaction rate. In a second part, the main findings of expert interviews are contrasted with the perceptions of the community at large which participated in the participatory planning process. A better understanding of community participation in urban settings is needed regarding skills, motivation, time, and defining the right levels of participation.
Water meanings, sanitation practices and hygiene behaviours in the cultural mirror: a perspective from Nigeria
Emmanuel M. Akpabio………. 168–181
This paper focuses on water meanings, sanitation practices and hygiene behaviours from a cultural perspective in southern Nigeria. Attention was directed on how cultural understanding of water influences sanitation practices as well as the challenges such a relationship poses on public health and sanitation programmes in rural Nigeria. A wide range of meanings, beliefs, values and taboos surrounded local notions and ideas of water and sanitation which were noted to determine available responsive practices and norms. Socio-economic characteristics, physical location and cultural factors were used in explaining the degrees, scale and impact of observed practices and norms across space and time. The paper argues that it will make more practical sense if water and sanitation problems are addressed within the cultural foundation, to understand the realities of local circumstances of beliefs and values, than applying the logic of pure science. This is very important in designing interventions to reduce risks in deeply cultural communities.
Assessment of social acceptance and scope of scaling up urine diversion dehydration toilets in Kenya
S. M. N. Uddin, V. S. Muhandiki, J. Fukuda, M. Nakamura and A. Sakai………. 182–189
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.
JOURNAL – AMERICAN WATER WORKS ASSOCIATION
VOL 104; NUMB 9 (2012)
Effect of storage tank material and maintenance on household water quality
Schafer, C.A.; Mihelcic, J.R.
VOL 46; NUMB 16 (2012)
Halophyte filter beds for treatment of saline wastewater from aquaculture
Webb, J. M.; Quinta, R.; Papadimitriou, S.; Norman, L.; Rigby, M.; Thomas, D. N.; Le Vay, L.
The expansion of aquaculture and the recent development of more intensive land-based marine farms require efficient and cost-effective systems for treatment of highly nutrient-rich saline wastewater. Constructed wetlands with halophytic plants offer the potential for waste-stream treatment combined with production of valuable secondary plant crops. Pilot wetland filter beds, constructed in triplicate and planted with the saltmarsh plant Salicornia europaea, were evaluated over 88 days under commercial operating conditions on a marine fish and shrimp farm. Nitrogen waste was primarily in the form of dissolved inorganic nitrogen (TDIN) and was removed by 98.2 +- 2.2% under ambient loadings of 109-383 mmol l-1. There was a linear relationship between TDIN uptake and loading over the range of inputs tested. At peak loadings of up to 8185 +- 590 mmol l-1 (equivalent to 600 mmol N m-2 d-1), the filter beds removed between 30 and 58% (250 mmol N m-2 d-1) of influent TDIN. Influent dissolved inorganic phosphorus levels ranged from 34 to 90 mmol l-1, with 36-89% reduction under routine operations. Dissolved organic nitrogen (DON) loadings were lower (11-144 mmol l-1), and between 23 and 69% of influent DON was removed during routine operation, with no significant removal of DON under high TDIN loading. Over the 88-day study, cumulative nitrogen removal was 1.28 mol m-2, of which 1.09 mol m-2 was retained in plant tissue, with plant uptake ranging from 2.4 to 27.0 mmol N g-1 dry weight d-1. The results demonstrate the effectiveness of N and P removal from wastewater from land-based intensive marine aquaculture farms by constructed wetlands planted with S. europaea.
Performance of a large building rainwater harvesting system
Ward, S.; Memon, F. A.; Butler, D.
Rainwater harvesting is increasingly becoming an integral part of the sustainable water management toolkit. Despite a plethora of studies modelling the feasibility of the utilisation of rainwater harvesting (RWH) systems in particular contexts, there remains a significant gap in knowledge in relation to detailed empirical assessments of performance. Domestic systems have been investigated to a limited degree in the literature, including in the UK, but there are few recent longitudinal studies of larger non-domestic systems. Additionally, there are few studies comparing estimated and actual performance. This paper presents the results of a longitudinal empirical performance assessment of a non-domestic RWH system located in an office building in the UK. Furthermore, it compares actual performance with the estimated performance based on two methods recommended by the British Standards Institute – the Intermediate (simple calculations) and Detailed (simulation-based) Approaches. Results highlight that the average measured water saving efficiency (amount of mains water saved) of the office-based RWH system was 87% across an 8-month period, due to the system being over-sized for the actual occupancy level. Consequently, a similar level of performance could have been achieved using a smaller-sized tank. Estimated cost savings resulted in capital payback periods of 11 and 6 years for the actual over-sized tank and the smaller optimised tank, respectively. However, more detailed cost data on maintenance and operation is required to perform whole life cost analyses. These findings indicate that office-scale RWH systems potentially offer significant water and cost savings. They also emphasise the importance of monitoring data and that a transition to the use of Detailed Approaches (particularly in the UK) is required to (a) minimise over-sizing of storage tanks and (b) build confidence in RWH system performance.
Effect of plant species on water quality at the outlet of a sludge treatment wetland
Gagnon, V.; Chazarenc, F.; Koiv, M.; Brisson, J.
Sludge treatment wetlands are mainly used to reduce the volume of activated sludge, and the pollutants at the outlet are generally returned to the wastewater treatment plant. However, in cases where sludges are produced far from treatment plants not only must the sludge be treated, but the discharge of pollutants into the surrounding environment must also be limited. The aim of this study was to evaluate the efficiency of different plant species in optimising pollutant removal in a decentralised sludge treatment wetland. In addition, a new system design was assessed, in which the wetland was not completely drained, and a saturated layer was created using an overflow. The experimental setup consisted of 16 mesocosms in total, planted with monocultures of Phragmites australis, Typha angustifolia and Scirpus fluviatilis, and unplanted controls, each in four replicates. The experiment was conducted during the third summer of operation after setup. The system was fed with highly concentrated fish farm sludge at a load of 30 kg of total solids m-2 yr-1. Results showed that such wetlands were highly efficient, with removal rates between 94% and 99% for most pollutants. Planted systems generally outperformed the unplanted control, with a significantly lower mass of pollutants at the outlet of the sludge treatment wetland planted with Phragmites, followed by those with Typha and then Scirpus. The distinct influence of plant species on pollution removal was explained by the sequestration of nitrogen and phosphorus in plant tissues and by the rhizosphere effect, which enhance the biodegradation of organic matter, allowed the nitrification process and created redox conditions favourable to the sorption of phosphorus. Filtration and evapotranspiration rates played a major role in limiting the discharge of pollutants, and the impact was enhanced by the fact that the sludge treatment wetland was not completely drained.
VOL 46; NUMB 17 (2012)
A shallow lake remediation regime with Phragmites australis: Incorporating nutrient removal and water evapotranspiration
Zhao, Y.; Yang, Z.; Xia, X.; Wang, F.
Shallow lake eutrophication has been an important issue of global water environment. Based on the simulation and field sampling experiments in Baiyangdian Lake, the largest shallow lake in North China, this study proposed a shallow lake remediation regime with Phragmites australis (reed) incorporating its opposite effects of nutrient removal and water evapotranspiration on water quality. The results of simulation experiments showed that both total nitrogen (TN) and phosphorus (TP) removal efficiencies increased with the increasing reed coverage. The TN removal efficiencies by reed aboveground uptake and rhizosphere denitrification were 11.2%, 13.8%, 22.6%, 28.4%, and 29.6% for the reed coverage of 20%, 40%, 60%, 80%, and 100%, respectively. Correspondingly, TP removal efficiencies by aboveground reed uptake were 1.4%, 2.5%, 4.4%, 7.4% and 7.9%, respectively. However, the water quality was best when the reed coverage was 60% (72 plants m-2). This was due to the fact that the concentration effect of reed evapotranspiration on nutrient increased with reed coverage. When the reed coverage was 100% (120 plants m-2), the evapotranspiration was approximately twice that without reeds. The field sampling results showed that the highest aboveground nutrient storages occurred in September. Thus, the proposed remediation regime for Baiyangdian Lake was that the reed coverage should be adjusted to 60%, and the aboveground biomass of reeds should be harvested in each September. With this remediation regime, TN and TP removal in Baiyangdian Lake were 117.8 and 4.0 g m-2, respectively, and the corresponding removal efficiencies were estimated to be 49% and 8.5% after six years. This study suggests that reed is an effective plant for the remediation of shallow lake eutrophication, and its contrasting effects of nutrient removal and evapotranspiration on water quality should be considered for establishing the remediation regime in the future.
SCIENCE OF THE TOTAL ENVIRONMENT
VOL 435; (2012)
Assessing rural small community water supply in Limpopo, South Africa: Water service benchmarks and reliability
Majuru, B.; Jagals, P.; Hunter, P. R.
Although a number of studies have reported on water supply improvements, few have simultaneously taken into account the reliability of the water services. The study aimed to assess whether upgrading water supply systems in small rural communities improved access, availability and potability of water by assessing the water services against selected benchmarks from the World Health Organisation and South African Department of Water Affairs, and to determine the impact of unreliability on the services. These benchmarks were applied in three rural communities in Limpopo, South Africa where rudimentary water supply services were being upgraded to basic services. Data were collected through structured interviews, observations and measurement, and multi-level linear regression models were used to assess the impact of water service upgrades on key outcome measures of distance to source, daily per capita water quantity and Escherichia coli count. When the basic system was operational, 72% of households met the minimum benchmarks for distance and water quantity, but only 8% met both enhanced benchmarks. During non-operational periods of the basic service, daily per capita water consumption decreased by 5.19l (p<0.001, 95% CI 4.06-6.31) and distances to water sources were 639m further (p 0.001, 95% CI 560-718). Although both rudimentary and basic systems delivered water that met potability criteria at the sources, the quality of stored water sampled in the home was still unacceptable throughout the various service levels. These results show that basic water services can make substantial improvements to water access, availability, potability, but only if such services are reliable.
WATER RESOURCES MANAGEMENT -DORDRECHT-
VOL 26; NUMB 13 (2012)
Resilience Assessment of Water Resources System
Liu, D.; Chen, X.; Nakato, T.
The resilience perspective, which emphasizes the integrated, systemic concept of human and nature interactions, is increasingly used as an approach for understanding the dynamic of social-ecological system. As the water resources system (WRS) is a social-ecological system, resilience thinking such as Holling’s adaptive cycle has been adopted as a fundamental unit for understanding the water resources system dynamics in this paper. In the adaptive cycle of WRS, the likelihood shift among different phases largely depends on resilience value; and a quantitative method for estimating the resilience of WRS is proposed. The method is related to the degree of change and characteristics of the WRS, and has been applied to identify the phase of WRS in every city in Zhejiang province, China. The results of resilience assessment have also been discussed in terms of adaptive cycle.
Urban Rainwater Utilization and its Role in Mitigating Urban Waterlogging Problems—A Case Study in Nanjing, China
Zhang, X.; Hu, M.; Chen, G.; Xu, Y.
With the acceleration of the urbanization process, urban waterlogging problems are becoming more and more serious in Nanjing, China. In order to mitigate the urban waterlogging problems, it is necessary to reduce surface runoff from the source by rainwater harvesting and utilization. An urban residential district with an area of 0.58 km2 in Nanjing was selected as the study area. Based on a large-scale topographic map data and the long term rainfall data (1951–2008), the types of underlying surfaces were classified. The potentiality of collectable rainwater and the possibility of runoff volume reduction were calculated. The results showed that exploitation of rainwater harvesting from rooftops and other underlying surfaces has high potential. The annual collectable rainwater is approximately 372,284 m3, 314,034 m3 and 275,180 m3 under different cumulative frequency of rainfall at 20 %, 50 % and 75 %, respectively. The total capacity of cisterns under assumptions of return period of rainfall and rainfall duration with 5 years and 20 min is 11,022 m3. The cistern’s capacity which is used for roof rainwater harvesting is 4,083 m3, the cistern capacity for per unit roof area (1 m2) is 0.0267 m3. The results of the feasibility analysis of setting up above-ground cisterns showed that 55 % of the total roof areas in the study area are available for setting up cisterns. In the three building types, 16 % of the commercial building’s roof areas and 77 % of that of the residential and the “others” buildings are available for setting up cisterns. Urban waterlogging problems can be effectively reduced through rainwater harvesting by 13.9 %, 30.2 % and 57.7 % of runoff volume reduction in three cases of the maximum daily rainfall (207.2 mm), the average annual maximum daily rainfall (95.5 mm) and the critical rainfall of rainstorm (50 mm).
Capacity Building as A Policy Instrument in Water Conservation: A Case Study on Commercial, Industrial, and Institutional Consumers
Reed, L. K.
Efforts by municipal water agencies to improve demand end water use efficiency have focused largely on incentive programs and regulatory interventions. However, another important approach to achieving conservation targets is capacity-building, which may be particularly effective when target populations are motivated to improve their consumption efficiency but are lacking information or technology to do so. This case study considers a program by the Santa Clara Valley Water District (CA, USA) which aims to enable conservation among a group of consumers by providing information about current use and potential savings as well as optional access to water saving devices. The impact of this capacity building approach on consumption patterns was quantified by comparing water histories of program participants to a control group of similar sites within the District. Participating sites showed a net savings of 18.22 % when compared to the control group. The study demonstrates that capacity building approaches can effectively compliment other interventions such as conservation incentives to improve demand end water use efficiency.