Chlorine dispensers in Kenya: scaling for results, 3ie Grantee Final Report, 2015.

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Authors: Amrita Ahuja, et al.

We conducted three studies: one survey experiment and two large-scale randomized evaluations, to investigate how a particular community-level water treatment device, the chlorine dispenser, is valued and allocated by local government officials, and how best it can be financed and managed.

The first study involved 179 elected county councilors in rural Kenya, who chose between different public goods packages in an incentivized survey. The public goods varied with respect to two attributes: how the location of the infrastructure was decided and who controlled the funding associated with maintaining it. We found that on average, councilors valued the opportunity to target the water treatment technology, but not the ability to control funding for maintenance.

The second study, Community Financed Dispensers (CFD) concerned how to finance the chlorine refills required to keep chlorine dispensers functional. The chlorine dispenser is a classic common good in that chlorine is rival in consumption, yet it is not practical to restrict access to it. 104 communities were randomly assigned to a free provision arm or one of four community financing arms. In the community financing arms, water source users were responsible for purchasing chlorine refills. In half of these, an upfront contribution to the cost of the dispenser was required prior to installation (“up-front payment” treatment); cross-cut with this was a “threat of removal” treatment, in which the dispenser was a portable model that could be removed if the community failed to stock it with chlorine. In free provision communities, permanent dispensers were installed and chlorine refills were provided at no cost. We found no effect of up-front payment on household chlorine usage three months after installation, nor on whether the dispenser contained chlorine at unannounced visits over a period of eleven months. In contrast, threat of removal led to a 20 percentage point increase in the probability that a dispenser was stocked relative to permanent community-financed dispensers, which were stocked 41% of the time. Further, we estimate that in communities receiving free refills, enough doses were consumed to consistently treat all households’ drinking water. Households in threat of removal communities consumed 28-30% of the
recommended doses and households in other communities consumed 20% of the recommended doses.

Effectiveness of Chlorine Dispensers in Emergencies: Case Study Results from Haiti, Sierra Leone, DRC, and Senegal. Environ. Sci. Technol., March 2015.

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Authors: Travis Yates , Elise Armitage , Lilian V. Lehmann , Ariel J. Branz , and Daniele S. Lantagne

Dispensers are a source-based water quality intervention with promising uptake results in development contexts. Dispenser programs include a tank of chlorine with a dosing valve that is installed next to a water source, a local Promoter who conducts community education and refills the Dispenser, and chlorine refills. In collaboration with response organizations, we assessed the effectiveness of Dispensers in four emergency situations.

In the three initial and four sustained response phase evaluations, 70 Dispenser sites were visited, 2,057 household surveys were conducted, and 1,676 water samples were analyzed. Across the evaluations, reported Dispenser use ranged from 9-97%, confirmed Dispenser use (as measured by free chlorine residual) ranged from 5-87%, and effective use (as measured by improvement in household water quality to meet international standards) ranged from 0-81%.

More effective Dispenser interventions installed Dispensers at point-sources, maintained a high-quality chlorine solution manufacturing and distribution chain, maintained Dispenser hardware, integrated Dispensers projects within larger water programs, remunerated Promoters, had experienced project staff, worked with local partners to implement the project, conducted ongoing monitoring, and had a project sustainability plan. Our results indicate that Dispensers can be, but are not always, an appropriate strategy to reduce the risk of waterborne diseases in emergencies.

Differences in Field Effectiveness and Adoption between a Novel Automated Chlorination System and Household Manual Chlorination of Drinking Water in Dhaka, Bangladesh: A Randomized Controlled Trial. PLoS One, March 2015.

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Authors: Amy J. Pickering , Yoshika Crider, Nuhu Amin, Valerie Bauza, Leanne Unicomb, Jennifer Davis, Stephen P. Luby

The number of people served by networked systems that supply intermittent and contaminated drinking water is increasing. In these settings, centralized water treatment is ineffective, while household-level water treatment technologies have not been brought to scale. This study compares a novel low-cost technology designed to passively (automatically) dispense chlorine at shared handpumps with a household-level intervention providing water disinfection tablets (Aquatab), safe water storage containers, and behavior promotion.

Twenty compounds were enrolled in Dhaka, Bangladesh, and randomly assigned to one of three groups: passive chlorinator, Aquatabs, or control. Over a 10-month intervention period, the mean percentage of households whose stored drinking water had detectable total chlorine was 75% in compounds with access to the passive chlorinator, 72% in compounds receiving Aquatabs, and 6% in control compounds. Both interventions also significantly improved microbial water quality. Aquatabs usage fell by 50% after behavioral promotion visits concluded, suggesting intensive promotion is necessary for sustained uptake. The study findings suggest high potential for an automated decentralized water treatment system to increase consistent access to clean water in low-income urban communities.

Differences in Field Effectiveness and Adoption between a Novel Automated Chlorination System and Household Manual Chlorination of Drinking Water in Dhaka, Bangladesh: A Randomized Controlled Trial. PLoS ONE, Mar 2015.

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Authors: Amy J. Pickering , Yoshika Crider, Nuhu Amin, Valerie Bauza, Leanne Unicomb, Jennifer Davis, Stephen P. Luby

The number of people served by networked systems that supply intermittent and contaminated drinking water is increasing. In these settings, centralized water treatment is ineffective, while household-level water treatment technologies have not been brought to scale.

This study compares a novel low-cost technology designed to passively (automatically) dispense chlorine at shared handpumps with a household-level intervention providing water disinfection tablets (Aquatab), safe water storage containers, and behavior promotion. Twenty compounds were enrolled in Dhaka, Bangladesh, and randomly assigned to one of three groups: passive chlorinator, Aquatabs, or control. Over a 10-month intervention period, the mean percentage of households whose stored drinking water had detectable total chlorine was 75% in compounds with access to the passive chlorinator, 72% in compounds receiving Aquatabs, and 6% in control compounds.

Both interventions also significantly improved microbial water quality. Aquatabs usage fell by 50% after behavioral promotion visits concluded, suggesting intensive promotion is necessary for sustained uptake. The study findings suggest high potential for an automated decentralized water treatment system to increase consistent access to clean water in low-income urban communities.

Methods to Test Chlorine Solution Concentrations in Ebola Emergencies, 2014.

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Daniele Lantagne, Tufts University.

Three alternate methods are described herein: 1) portable iodimetric titration kits; 2) dilution followed by testing with FCR/TCR test kits; and, 3) calculation based on manufacturing.

Methods to Make Chlorine Solution in Ebola Emergencies, 2014.

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Daniele Lantagne, Tufts University.

Chlorine solution is widely used for disinfection in emergency response activities. In Ebola response,0.5%chlorine solution is recommended for cleaning non-­living things and surfaces and 0.05% chlorine solution is recommended for cleaning living things.

The methods for on-­site manufacturing include: 1) dilution of HTH or NaDCC powder in water; 2) dilution of concentrated liquid solution in water; and, 3) generating sodium hypochlorite using salt,water,and electricity.

Factors involved in sustained use of point-of-use water disinfection methods: A field study from Flores Island, Indonesia. Journal of Water and Health, In Press, Uncorrected Proof © IWA Publishing 2014 | doi:10.2166/wh.2014.109

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E. Roma, T. Bond and P. Jeffrey
Cranfield University, Water Science Institute, Cranfield, MK430AL, UK E-mail: elisa.roma@lshtm.ac.uk
Environmental Health Group, London School of Hygiene and Tropical Medicine, WC17HT, London, UK
Civil and Environmental Engineering, Skempton Building, Imperial College, London, UK

Many scientific studies have suggested that point-of-use water treatment can improve water quality and reduce the risk of infectious diseases. Despite the ease of use and relatively low cost of such methods, experience shows the potential benefits derived from provision of such systems depend on recipients’ acceptance of the technology and its sustained use. To date, few contributions have addressed the problem of user experience in the post-implementation phase.

This can diagnose challenges, which undermine system longevity and its sustained use. A qualitative evaluation of two household water treatment systems, solar disinfection (SODIS) and chlorine tablets (Aquatabs), in three villages was conducted by using a diagnostic tool focusing on technology performance and experience. Cross-sectional surveys and in-depth interviews were used to investigate perceptions of involved stakeholders (users, implementers and local government).

Results prove that economic and functional factors were significant in using SODIS, whilst perceptions of economic, taste and odour components were important in Aquatabs use. Conclusions relate to closing the gap between factors that technology implementers and users perceive as key to the sustained deployment of point-of-use disinfection technologies.

Household Water Treatment Uptake during a Public Health Response to a Large Typhoid Fever Outbreak in Harare, Zimbabwe. Am Jnl Trop Med Hyg, Mar 2014.

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Authors: Maho Imanishi, et al.

Locally manufactured sodium hypochlorite (chlorine) solution has been sold in Zimbabwe since 2010. During October 1, 2011–April 30, 2012, 4,181 suspected and 52 confirmed cases of typhoid fever were identified in Harare. In response to this outbreak, chlorine tablets were distributed. To evaluate household water treatment uptake, we conducted a survey and water quality testing in 458 randomly selected households in two suburbs most affected by the outbreak.

Although 75% of households were aware of chlorine solution and 85% received chlorine tablets, only 18% had reportedly treated stored water and had the recommended protective level of free chlorine residuals. Water treatment was more common among households that reported water treatment before the outbreak, and those that received free tablets during the outbreak, but was not associated with chlorine solution awareness or use before the outbreak. Outbreak response did not build on pre-existing prevention programs.

Household Effectiveness vs. Laboratory Efficacy of Point-of-use Chlorination. Water Research, Jan 2014.

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Karen Levy, et al.

Highlights

• The effectiveness of chlorine water treatment under household conditions was lower than laboratory efficacy.
• Only 39-51% of stored water was safe for consumption and only 35-53% achieved recommended residual levels of chlorine.
• Chlorine treatment was not protective against diarrhea by WHO standards.
• Point-of-use interventions should take source water conditions such as baseline contamination and turbidity into account.

Treatment of water at the household level offers a promising approach to combat the global burden of diarrheal diseases. In particular, chlorination of drinking water has been a widely promoted strategy due to persistence of residual chlorine after initial treatment. However, the degree to which chlorination can reduce microbial levels in a controlled setting (efficacy) or in a household setting (effectiveness) can vary as a function of chlorine characteristics, source water characteristics, and household conditions. To gain more understanding of these factors, we carried out an observational study within households in rural communities of northern coastal Ecuador. We found that the efficacy of chlorine treatment under controlled conditions was significantly better than its effectiveness when evaluated both by ability to meet microbiological safety standards and by log reductions. Water treated with chlorine achieved levels of microbial contamination considered safe for human consumption after 24 hours of storage in the household only 39 – 51% of the time, depending on chlorine treatment regimen.

Chlorine treatment would not be considered protective against diarrheal disease according to WHO log reduction standards. Factors that explain the observed compromised effectiveness include: source water turbidity, source water baseline contamination levels, and in-home contamination. Water in 38% of the households that had low turbidity source water (< 10 NTU) met the safe water standard as compared with only 17% of the households that had high turbidity source water (> 10 NTU). A 10 MPN/100mL increase in baseline E. coli levels was associated with a 2.2% increase in failure to meet the E. coli standard. Higher mean microbial contamination levels in 54% of household samples in comparison to their matched controls, which is likely the result of in-home contamination during storage. Container characteristics (size of the container mouth) did not influence chlorine effectiveness.

We found no significant differences between chlorine treatment regimens in ability to meet the safe water standards or in overall log reductions, although chlorine dosage did modify the effect of source conditions. These results underscore the importance of measuring both source water and household conditions to determine appropriate chlorine levels, as well as to evaluate the appropriateness of chlorine treatment and other point-of-use water quality improvement interventions.

Increasing acceptance of chlorination for household water treatment: observations from Bangladesh. Waterlines, Apr 2013.

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S. Flanagan, et al.

Point-of-use water treatment, especially chlorination, is an effective intervention to reduce diarrhoea, a leading cause of death for children under five. Yet success in chlorination uptake has been limited. One obstacle is objection to treated water’s taste/odour. Protective chlorine residuals that are not offensive to users require accurate dosing – a challenge in practice. Further, taste sensitivity may be different for populations never exposed to chlorinated water.

Here, household chlorination trials in Bangladesh similarly revealed dissatisfaction with treated water due to taste and odour, although attempts to quantifychlorine sensitivity disputed the dissatisfaction at lower residuals. A granular activated carbon (GAC) filter fitted to the spigot of a covered tank removed the remaining chlorine residual prior to drinking and increased user satisfaction. Such a filter removes taste as a barrier and allows over-dosing contaminated water to ensure disinfection, with implications for areas with high source water variability and for emergency situations.