Evan A. Thomas

Assessing the Impact of Water Filters and Improved Cook Stoves on Drinking Water Quality and Household Air Pollution: A Randomised Controlled Trial in Rwanda

Diarrhoea and respiratory infections remain the biggest killers of children under 5 years in developing countries. We conducted a 5-month household randomised controlled trial among 566 households in rural Rwanda to assess uptake, compliance and impact on environmental exposures of a combined intervention delivering high-performance water filters and improved stoves for free. Compliance was measured monthly by self-report and spot-check observations. Semi-continuous 24-h PM2.5 monitoring of the cooking area was conducted in a random subsample of 121 households to assess household air pollution, while samples of drinking water from all households were collected monthly to assess the levels of thermotolerant coliforms. Adoption was generally high, with most householders reporting the filters as their primary source of drinking water and the intervention stoves as their primary cooking stove. However, some householders continued to drink untreated water and most continued to cook on traditional stoves. The intervention was associated with a 97.5% reduction in mean faecal indicator bacteria (Williams means 0.5 vs. 20.2 TTC/100 mL, p<0.001) and a median reduction of 48% of 24-h PM2.5 concentrations in the cooking area (p = 0.005). Further studies to increase compliance should be undertaken to better inform large-scale interventions. Trial registration: Clinicaltrials.gov; NCT01882777; http://clinicaltrials.gov/ct2/results?term=NCT01882777&Search=Search

Designing and Piloting a Program to Provide Water Filters and Improved Cookstoves in Rwanda

Background In environmental health interventions addressing water and indoor air quality, multiple determinants contribute to adoption. These may include technology selection, technology distribution and education methods, community engagement with behavior change, and duration and magnitude of implementer engagement. In Rwanda, while the country has the fastest annual reduction in child mortality in the world, the population is still exposed to a disease burden associated with environmental health challenges. Rwanda relies both on direct donor funding and coordination of programs managed by international non-profits and health sector businesses working on these challenges. Methods and Findings This paper describes the design, implementation and outcomes of a pilot program in 1,943 households across 15 villages in the western province of Rwanda to distribute and monitor the use of household water filters and improved cookstoves. Three key program design criteria include a.) an investment in behavior change messaging and monitoring through community health workers, b.) free distributions to encourage community-wide engagement, and c.) a private-public partnership incentivized by a business model designed to encourage “pay for performance”. Over a 5-month period of rigorous monitoring, reported uptake was maintained at greater than 90% for both technologies, although exclusive use of the stove was reported in only 28.5% of households and reported water volume was 1.27 liters per person per day. On-going qualitative monitoring suggest maintenance of comparable adoption rates through at least 16 months after the intervention. Conclusion High uptake and sustained adoption of a water filter and improved cookstove was measured over a five-month period with indications of continued comparable adoption 16 months after the intervention. The design attributes applied by the implementers may be sufficient in a longer term. In particular, sustained and comprehensive engagement by the program implementer is enabled by a pay-for-performance business model that rewards sustained behavior change.

Behavioral Reactivity Associated With Electronic Monitoring of Environmental Health Interventions-A Cluster Randomized Trial with Water Filters and Cookstoves

Subject reactivity--when research participants change their behavior in response to being observed--has been documented showing the effect of human observers. Electronics sensors are increasingly used to monitor environmental health interventions, but the effect of sensors on behavior has not been assessed. We conducted a cluster randomized controlled trial in Rwanda among 170 households (70 blinded to the presence of the sensor, 100 open) testing whether awareness of an electronic monitor would result in a difference in weekly use of household water filters and improved cookstoves over a four-week surveillance period. A 63% increase in number of uses of the water filter per week between the groups was observed in week 1, an average of 4.4 times in the open group and 2.83 times in the blind group, declining in week 4 to an insignificant 55% difference of 2.82 uses in the open, and 1.93 in the blind. There were no significant differences in the number of stove uses per week between the two groups. For both filters and stoves, use decreased in both groups over four-week installation periods. This study suggests behavioral monitoring should attempt to account for reactivity to awareness of electronic monitors that persists for weeks or more.

Impact of wastewater fouling on contact angle

Capillary dependent systems are highly influenced by surface fouling and may degrade as material surface properties change. In anticipation of a spacecraft microgravity fluids management system exposed to highly variable wetting conditions, the impact of urine wastewater fouling on capillary contact angle was examined. The results indicate that, in general, surface fouling can decrease the contact angle when crystalline structures or biofilms form. Small crystalline growth on the order of 10 μm can lower advancing contact angles θadv by approximately 30°, while biofilm growth can lower it by approximately 15°. Vacuum drying of fouled surfaces increased θadv by about 8°, and defects greater in height than 5% of the capillary length increased θadv by approximately 30°. These trends may indicate that promotion of wastewater fouling may improve the performance of capillary dependent fluids management systems. These results may also influence terrestrial technologies, including medical catheters and sustainable wastewater treatment systems exposed to wastewater fouling.

Assessing Latrine Use in Rural India: A Cross-Sectional Study Comparing Reported Use and Passive Latrine Use Monitors

Although large-scale programs, like Indias Total Sanitation Campaign (TSC), have improved latrine coverage in rural settings, evidence suggests that actual use is suboptimal. However, the reliability of methods to assess latrine use is uncertain. We assessed the reliability of reported use, the standard method, by comparing survey-based responses against passive latrine use monitors (PLUMs) through a cross-sectional study among 292 households in 25 villages in rural Odisha, India, which recently received individual household latrines under the TSC. PLUMs were installed for 2 weeks and householders responded to surveys about their latrine use behavior. Reported use was compared with PLUM results using Bland–Altman (BA) plots and concordance statistics. Reported use was higher than corresponding PLUM-recorded events across the range of comparisons. The mean reported “usual” daily events per household (7.09, 95% confidence interval [CI] = 6.51, 7.68) was nearly twice that of the PLUM-recorded daily average (3.62, 95% CI = 3.29, 3.94). There was poor agreement between “usual” daily latrine use and the average daily PLUM-recorded events (ρc = 0.331, 95% CI = 0.242, 0.427). Moderate agreement (ρc = 0.598, 95% CI = 0.497, 0.683) was obtained when comparing daily reported use during the previous 48 hours with the average daily PLUM count. Reported latrine use, though already suggesting suboptimal adoption, likely exaggerates the actual level of uptake of latrines constructed under the program. Where reliance on self-reports is used, survey questions should focus on the 48 hours prior to the date of the survey rather than asking about “usual” latrine use behavior.

Study design of a cluster-randomized controlled trial to evaluate a large-scale distribution of cook stoves and water filters in Western Province, Rwanda

Background In Rwanda, pneumonia and diarrhea are the first and second leading causes of death, respectively, among children under five. Household air pollution (HAP) resultant from cooking indoors with biomass fuels on traditional stoves is a significant risk factor for pneumonia, while consumption of contaminated drinking water is a primary cause of diarrheal disease. To date, there have been no large-scale effectiveness trials of programmatic efforts to provide either improved cookstoves or household water filters at scale in a low-income country. In this paper we describe the design of a cluster-randomized trial to evaluate the impact of a national-level program to distribute and promote the use of improved cookstoves and advanced water filters to the poorest quarter of households in Rwanda. Methods/Design We randomly allocated 72 sectors (administratively defined units) in Western Province to the intervention, with the remaining 24 sectors in the province serving as controls. In the intervention sectors, roughly 100,000 households received improved cookstoves and household water filters through a government-sponsored program targeting the poorest quarter of households nationally. The primary outcome measures are the incidence of acute respiratory infection (ARI) and diarrhea among children under five years of age. Over a one-year surveillance period, all cases of acute respiratory infection (ARI) and diarrhea identified by health workers in the study area will be extracted from records maintained at health facilities and by community health workers (CHW). In addition, we are conducting intensive, longitudinal data collection among a random sample of households in the study area for in-depth assessment of coverage, use, environmental exposures, and additional health measures. Discussion Although previous research has examined the impact of providing household water treatment and improved cookstoves on child health, there have been no studies of national-level programs to deliver these interventions at scale in a developing country. The results of this study, the first RCT of a large-scale programmatic cookstove or household water filter intervention, will inform global efforts to reduce childhood morbidity and mortality from diarrheal disease and pneumonia. Trial registration This trial is registered at Clinicaltrials.gov (NCT02239250).

Proving Sustainability: The International Development Monitoring Initative

Nearly a billion people in the world lack access to safe drinking water, two billion have inadequate sanitation facilities, three billion use biomass for their daily energy needs and nearly half the worlds population live in rural isolation, lacking access to the most basic human services. Combined, these limitations are a leading cause of the perpetuating cycle of poverty and political insecurity. Meanwhile, the majority of international development agencies are responsible for self-reporting project outcomes. At best, expert spot-checks are conducted in the field occasionally. These results tend to show individual project success, while meta-surveys indicate on-going challenges in the sector. This disconnect may be addressed through independent data monitoring technologies that provide objective data on system performance and use and can be used to demonstrate success and identify project weaknesses. By demonstrating which technologies and programs are truly successful, these successes can be targeted for scaling, through savings realized by eliminating unsuccessful approaches. This will benefit developing communities by providing proven and accountable programs. The Sustainable Water, Energy and Environmental Technologies Laboratory, the SWEETLab™, at Portland State University is working with partners to demonstrate this concept across several applications and countries. The SWEETSense™ technology can provide objective, qualitative and continuous operational data on the usage and performance of programs across a range of sectors and communities. The data is then directly integrated into SWEETData™, an internet database presenting summary statistics on performance and usage of the monitored technologies to front-end users. The SWEETLab™ is currently demonstrating this concept in water, sanitation, household energy and rural infrastructure programs with diverse partners including Mercy Corps, the Lemelson Foundation, Bridges to Prosperity, Manna Energy Limited and Vestergaard Frandsen, in several countries including Indonesia, Haiti, Guatemala and Rwanda. Remote monitoring systems are an innovative method to ensure the success of appropriate technology projects. Rather than infrequent engagement, remote monitoring systems ensure that community partnerships are maintained through continuous monitoring. This approach seeks to raise the quality and accountability of these projects internationally.

Development and Implementation of the Bring Your Own Water Treatment System in Dense, Rural, and Mountainous Rwandan Communities

Over a billion people in the world lack access to safe drinking water 1 . While numerous technological, medical, and educational solutions have been implemented for the benefi t of disadvantaged communities, there is no ‘magic bullet’. Instead, development agencies must partner directly with these communities to address their public health needs through appropriate technology solutions, backed up by education and assessment. The “Bring Your Own Water (BYOW) Treatment System” developed by the Engineers Without Borders-USA chapters at the University of Colorado at Boulder Chapter (EWB-CU) and the Johnson Space Center (EWB-JSC) is uniquely designed to address the water treatment requirements of two poor and overpopulated Rwandan communities. The BYOW system consists of a gravity-fed roughing fi lter, rapid sand fi lter, and solar-powered ultraviolet irradiation system. The BYOW system treats water collected in containers by local residents from any contaminated or suspect source. A key component is a self-fi lling tank for backwashing of the fi lter. The system treats water at a rate of approximately 10 liters per minute, and can provide up to 5,000 liters of treated water per day. The BYOW system performed successfully in long term tests in Houston, Texas. Activated sludge collected from a municipal sewage plant (over 70 NTU turbidity, 3,000 CFU/ml E. Coli) was introduced as input. The BYOW-treated effl uent water was signifi cantly cleaner (less than one NTU, 0-2 CFU/ml E. Coli). A system installed in Muramba in 2006 was well accepted by users. A second iteration with signifi cant improvements was installed in Mugonero in 2007. After two months of community testing, water quality results indicate that rainwater passed through the Mugonero BYOW system was reduced from up to 60 CFUs/ml coliform bacteria and up to 4.5 NTU turbidity to zero CFUs/ml and less than 2.25 NTU. The BYOW system has the potential to be replicated around the world where communities have similar water treatment requirements, and no available treatment infrastructure or surplus energy resources.

Second-generation International Space Station Total Organic Carbon Analyzer Verification Testing and On-orbit Performance Results

N support of a crew of six on board the International Space Station (ISS), wastewater and urine is reclaimed and reprocessed into potable water. The ISS regenerative water processing assembly (WPA) purifies wastewater into potable water for consumption and oxygen (O 2) generation on station. The total organic carbon analyzer (TOCA) takes samples of WPA water and analyzes them for the presence of total organic carbon (TOC). Measuring TOC in the water provides a general assessment of water quality. Low TOC indicates the water processor is likely functioning properly. The WPA, which also contains conductivity sensors to monitor water quality, directs re-processing if water quality parameters are not met. These conductivity sensors are the first and second controls for water quality on ISS, and TOCA serves as the third control to out-of-specification potable water. The TOCA was designed to be a standalone, re-deployable piece of hardware that performs off-line sampling of regenerated potable water from the WPA. TOCA is located close to the Water Recovery System (WRS) rack to enable direct sampling from the WPA. It can also receive samples via a sample bag, which is normally filled from the potable water dispenser (PWD) on orbit. Several principles of TOC analysis are listed below:  Total carbon (TC) = total inorganic carbon (TIC) + TOC  TIC interferes with the direct measurement of TOC and must be removed prior to measuring TOC  TOCA converts and removes TIC by creating a pH shift with a slightly acidic buffer that forces inorganic carbon species into carbon dioxide (CO 2) gas  TOCA oxidizes the organic carbon species remaining in the sample water to CO 2 gas  TOCA-produced CO 2 gas is measured using a very precise infrared (IR) CO 2 detector

Ensemble Machine Learning and Forecasting can Achieve 99% Uptime for Rural Handpumps

Broken water pumps continue to impede efforts to deliver clean and economically-viable water to the global poor. The literature has demonstrated that customers’ health benefits and willingness to pay for clean water are best realized when clean water infrastructure performs extremely well (>99% uptime). In this paper, we used sensor data from 42 Afridev-brand handpumps observed for 14 months in western Kenya to demonstrate how sensors and supervised ensemble machine learning could be used to increase total fleet uptime from a best-practices baseline of about 70% to >99%. We accomplish this increase in uptime by forecasting pump failures and identifying existing failures very quickly. Comparing the costs of operating the pump per functional year over a lifetime of 10 years, we estimate that implementing this algorithm would save 7% on the levelized cost of water relative to a sensor-less scheduled maintenance program. Combined with a rigorous system for dispatching maintenance personnel, implementing this algorithm in a real-world program could significantly improve health outcomes and customers’ willingness to pay for water services.