Remotely Accessible Instrumented Monitoring of Global Development Programs: Technology Development and Validation. Sustainability 2013, 5(8), 3288-3301; doi:10.3390/su5083288.
Evan Thomas, et al.
Many global development agencies self-report their project outcomes, often relying on subjective data that is collected sporadically and communicated months later. These reports often highlight successes and downplay challenges. Instrumented monitoring via distributed data collection platforms may provide crucial evidence to help inform the sector and public on the effectiveness of aid, and the on-going challenges.
This paper presents the process of designing and validating an integrated sensor platform with cellular-to-internet reporting purposely targeted at global development programs. The integrated hardware platform has been applied to water, sanitation, energy and infrastructure interventions and validated through laboratory calibration and field observations.
Presented here are two examples: a water pump and a household water filter, wherein field observations agreed with the data algorithm with a linear fit slope of between 0.91 and 1, and an r-squared of between 0.36 and 0.39, indicating a wide confidence interval but with low overall error (i.e., less than 0.5% in the case of structured field observations of water volume added to a household water filter) and few false negatives or false positives.
Comparative study of disinfectants for use in low-cost gravity driven household water purifiers. Journal of Water and Health, June 2013.
Rajshree A., et al. TCS Innovation Labs – TRDDC, 54B, Hadapsar Industrial Estate, Pune – 411013, India E-mail: shankar.kausley@tcs.com
Point-of-use (POU) gravity-driven household water purifiers have been proven to be a simple, low-cost and effective intervention for reducing the impact of waterborne diseases in developing countries. The goal of this study was to compare commonly used water disinfectants for their feasibility of adoption in low-cost POU water purifiers. The potency of each candidate disinfectant was evaluated by conducting a batch disinfection study for estimating the concentration of disinfectant needed to inactivate a given concentration of the bacterial strain Escherichia coli ATCC 11229. Based on the concentration of disinfectant required, the size, weight and cost of a model purifier employing that disinfectant were estimated.
Model purifiers based on different disinfectants were compared and disinfectants which resulted in the most safe, compact and inexpensive purifiers were identified. Purifiers based on bromine, tincture iodine, calcium hypochlorite and sodium dichloroisocyanurate were found to be most efficient, cost effective and compact with replacement parts costing US$ 3.60–6.00 for every 3,000 L of water purified and are thus expected to present the most attractive value proposition to end users.
Cluster-randomised controlled trials of individual and combined water, sanitation, hygiene and nutritional interventions in rural Bangladesh and Kenya: the WASH Benefits study design and rationale. BMJ Open 2013;3:e003476 doi:10.1136/bmjopen-2013-003476.
Benjamin F Arnold, et al.
Introduction – Enteric infections are common during the first years of life in low-income countries and contribute to growth faltering with long-term impairment of health and development. Water quality, sanitation, handwashing and nutritional interventions can independently reduce enteric infections and growth faltering. There is little evidence that directly compares the effects of these individual and combined interventions on diarrhoea and growth when delivered to infants and young children. The objective of the WASH Benefits study is to help fill this knowledge gap.
Methods and analysis – WASH Benefits includes two cluster-randomised trials to assess improvements in water quality, sanitation, handwashing and child nutrition—alone and in combination—to rural households with pregnant women in Kenya and Bangladesh. Geographically matched clusters (groups of household compounds in Bangladesh and villages in Kenya) will be randomised to one of six intervention arms or control. Intervention arms include water quality, sanitation, handwashing, nutrition, combined water+sanitation+handwashing (WSH) and WSH+nutrition. The studies will enrol newborn children (N=5760 in Bangladesh and N=8000 in Kenya) and measure outcomes at 12 and 24 months after intervention delivery. Primary outcomes include child length-for-age Z-scores and caregiver-reported diarrhoea. Secondary outcomes include stunting prevalence, markers of environmental enteropathy and child development scores (verbal, motor and personal/social). We will estimate unadjusted and adjusted intention-to-treat effects using semiparametric estimators and permutation tests.
Evaluating the Sustainability of Ceramic Filters for Point-of-Use Drinking Water Treatment. Environ. Sci. Technol., Aug 30, 2013.
Dianjun Ren, et al.
This study evaluates the social, economic, and environmental sustainability of ceramic filters impregnated with silver nano-particles for point-of-use (POU) drinking water treatment in developing countries. The functional unit for this analysis was the amount of water consumed by a typical household over ten years (37,960 L), as delivered by either the POU technology or a centralized water treatment and distribution system. Results indicate that the ceramic filters are 3-6 times more cost-effective than the centralized water system for reduction of waterborne diarrheal illness among the general population and children under five.
The ceramic filters also exhibit better environmental performance for four of five evaluated life cycle impacts: energy use, water use, global warming potential, and particulate matter emissions (PM10). For smog formation potential, the centralized system is preferable to the ceramic filter POU technology. This convergence of social, economic, environmental criteria offers clear indication that the ceramic filter POU technology is a more sustainable choice for drinking water treatment in developing countries than the centralized treatment systems that have been widely adopted in industrialized countries.
Effect of Household-Based Drinking Water Chlorination on Diarrhoea among Children under Five in Orissa, India: A Double-Blind Randomised Placebo-Controlled Trial. PLoS Med. 2013 August; 10(8): e1001497.
Sophie Boisson, et al.
Background – Boiling, disinfecting, and filtering water within the home can improve the microbiological quality of drinking water among the hundreds of millions of people who rely on unsafe water supplies. However, the impact of these interventions on diarrhoea is unclear. Most studies using open trial designs have reported a protective effect on diarrhoea while blinded studies of household water treatment in low-income settings have found no such effect. However, none of those studies were powered to detect an impact among children under five and participants were followed-up over short periods of time. The aim of this study was to measure the effect of in-home water disinfection on diarrhoea among children under five.
Methods and Findings – We conducted a double-blind randomised controlled trial between November 2010 and December 2011. The study included 2,163 households and 2,986 children under five in rural and urban communities of Orissa, India. The intervention consisted of an intensive promotion campaign and free distribution of sodium dichloroisocyanurate (NaDCC) tablets during bi-monthly households visits. An independent evaluation team visited households monthly for one year to collect health data and water samples. The primary outcome was the longitudinal prevalence of diarrhoea (3-day point prevalence) among children aged under five. Weight-for-age was also measured at each visit to assess its potential as a proxy marker for diarrhoea. Adherence was monitored each month through caregiver’s reports and the presence of residual free chlorine in the child’s drinking water at the time of visit. On 20% of the total household visits, children’s drinking water was assayed for thermotolerant coliforms (TTC), an indicator of faecal contamination. The primary analysis was on an intention-to-treat basis. Binomial regression with a log link function and robust standard errors was used to compare prevalence of diarrhoea between arms. We used generalised estimating equations to account for clustering at the household level. The impact of the intervention on weight-for-age z scores (WAZ) was analysed using random effect linear regression.
Over the follow-up period, 84,391 child-days of observations were recorded, representing 88% of total possible child-days of observation. The longitudinal prevalence of diarrhoea among intervention children was 1.69% compared to 1.74% among controls. After adjusting for clustering within household, the prevalence ratio of the intervention to control was 0.95 (95% CI 0.79–1.13). The mean WAZ was similar among children of the intervention and control groups (−1.586 versus −1.589, respectively). Among intervention households, 51% reported their child’s drinking water to be treated with the tablets at the time of visit, though only 32% of water samples tested positive for residual chlorine. Faecal contamination of drinking water was lower among intervention households than controls (geometric mean TTC count of 50 [95% CI 44–57] per 100 ml compared to 122 [95% CI 107–139] per 100 ml among controls [p<0.001] [n = 4,546]).
Conclusions – Our study was designed to overcome the shortcomings of previous double-blinded trials of household water treatment in low-income settings. The sample size was larger, the follow-up period longer, both urban and rural populations were included, and adherence and water quality were monitored extensively over time. These results provide no evidence that the intervention was protective against diarrhoea. Low compliance and modest reduction in water contamination may have contributed to the lack of effect. However, our findings are consistent with other blinded studies of similar interventions and raise additional questions about the actual health impact of household water treatment under these conditions.
Tapping the Market Opportunities for Domestic Investments in Water for the Poor, 2013.
World Bank; WSP; IFIC.
This report examines piped water schemes in rural areas of Bangladesh, Benin, and Cambodia, where the local private sector already plays a major role in the delivery of water (for the purposes of this study, the term “rural” also includes small towns outside of the main urban areas). The majority of households in all three countries currently get their water from private and communal sources. Little systematic information is available about these markets, however; most information on the private water sector focuses on large service providers.
The study examines the performance of networks in each country and investigates the preferences of poor households in locations served by them. It also examines commercial and investment climate factors that may affect firms’ actual or perceived costs and risks, driving their decisions about increasing investment in their business. Specifically, the study seeks answers to the following questions:
- Is lack of interest by the domestic private sector a rational response to weak market potential, or are lack of firm viability and the use of inappropriate business models preventing it from taking advantage of market opportunities?
- Are policy and investment climate factors increasing the (actual or perceived) cost and risk associated with doing business?
Water flows, energy demand, and market analysis of the informal water sector in Kisumu, Kenya. Ecol Econ. 2013 March 1; 87: 137–144.
Laura C. Sima, et al.
In rapidly growing urban areas of developing countries, infrastructure has not been able to cope with population growth. Informal water businesses fulfill unmet water supply needs, yet little is understood about this sector. This paper presents data gathered from quantitative interviews with informal water business operators (n=260) in Kisumu, Kenya, collected during the dry season. Sales volume, location, resource use, and cost were analyzed by using material flow accounting and spatial analysis tools.
Estimates show that over 76% of the city’s water is consumed by less than 10% of the population who have water piped into their dwellings. The remainder of the population relies on a combination of water sources, including water purchased directly from kiosks (1.5 million m3 per day) and delivered by hand-drawn water-carts (0.75 million m3 per day). Energy audits were performed to compare energy use among various water sources in the city. Water delivery by truck is the highest per cubic meter energy demand (35 MJ/m3), while the city’s tap water has the highest energy use overall (21,000 MJ/day).
We group kiosks by neighborhood and compare sales volume and cost with neighborhood-level population data. Contrary to popular belief, we do not find evidence of price gouging; the lowest prices are charged in the highest-demand low-income area. We also see that the informal sector is sensitive to demand, as the number of private boreholes that serve as community water collection points are much larger where demand is greatest.
Plasma-treated CNTs key to safer drinking water | Source: The Engineer – Aug 2013 |
An international team of researchers has developed a method of water purification that uses membranes enhanced by plasma-treated carbon nanotubes.
The team – led by Associate Professor Hui Ying Yang from Singapore University of Technology and Design – showed in their study that the new method removed contaminants and brine from water. The team included Dr Zhaojun Han and Professor Kostya (Ken) Ostrikov from CSIRO’s Plasma Nanoscience Laboratories.
The study, published in Nature Communications, is said to pave the way for the next generation of portable water purification devices, which could provide relief to the 780 million people around the world without access to clean water.
According to Dr Han, these membranes could be integrated into portable water purification devices the size of a tea pot that would be rechargeable, inexpensive and more effective than many existing filtration methods. Contaminated water would go in one end, and clean drinkable water would come out the other.
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H2S as an Indicator of Water Supply Vulnerability and Health Risk in Low-Resource Settings: A Prospective Cohort Study. Am. J. Trop. Med. Hyg., 89(2), 2013, pp. 251–259.
Ranjiv S. Khush, et al
Abstract. In this large-scale longitudinal study conducted in rural Southern India, we compared a presence/absence hydrogen sulfide (H2S) test with quantitative assays for total coliforms and Escherichia coli as measures of water quality, health risk, and water supply vulnerability to microbial contamination. None of the three indicators showed a significant association with child diarrhea. The presence of H2S in a water sample was associated with higher levels of total coliform species that may have included E. coli but that were not restricted to E. coli.
In addition, we observed a strong relationship between the percent positive H2S test results and total coliform levels among water source samples (R2 = 0.87). The consistent relationships between H2S and total coliform levels indicate that presence/absence of H2S tests provide a cost-effective option for assessing both the vulnerability of water supplies to microbial contamination and the results of water quality management and risk mitigation efforts.
Adapting Enzyme-Based Microbial Water Quality Analysis to Remote Areas in Low-Income Countries. Environ. Sci. Technol., Aug 2013.
Adam Abramson, et al.
Enzyme-substrate microbial water tests, originally developed for efficiency gains in laboratory settings, are potentially useful for on-site analysis in remote settings. This is especially relevant in developing countries where water quality is a pressing concern and qualified laboratories are rare. We investigated one such method, Colisure®, first for sensitivity to incubation temperatures in order to explore alternative incubation techniques appropriate for remote areas, and then in a remote community of Zambia for detection of total coliforms and Escherichia coli in drinking-water samples.
We sampled and analyzed 352 water samples from source, transport containers and point-of-use from 164 random households. Both internal validity (96–100%) and laboratory trials (zero false negatives or positives at incubation between 30 and 40 °C) established reliability under field conditions. We therefore recommend the use of this and other enzyme-based methods for remote applications. We also found that most water samples from wells accessing groundwater were free of E. coli whereas most samples from surface sources were fecally contaminated. We further found very low awareness among the population of the high levels of recontamination in household storage containers, suggesting the need for monitoring and treatment beyond the water source itself.
