Barbara Evans

On-plot drinking water supplies and health: a systematic review

Many studies have found that household access to water supplies near or within the household plot can reduce the probability of diarrhea, trachoma, and other water-related diseases, and it is generally accepted that on-plot water supplies produce health benefits for households. However, the body of research literature has not been analyzed to weigh the evidence supporting this. A systematic review was conducted to investigate the impacts of on-plot water supplies on diarrhea, trachoma, child growth, and water-related diseases, to further examine the relationship between household health and distance to water source and to assess whether on-plot water supplies generate health gains for households. Studies provide evidence that households with on-plot water supplies experience fewer diarrheal and helminth infections and greater child height. Findings suggest that water-washed (hygiene associated) diseases are more strongly impacted by on-plot water access than waterborne diseases. Few studies analyzed the effects of on-plot water access on quantity of domestic water used, hygiene behavior, and use of multiple water sources, and the lack of evidence for these relationships reveals an important gap in current literature. The review findings indicate that on-plot water access is a useful health indicator and benchmark for the progressive realization of the Sustainable Development Goal target of universal safe water access as well as the human right to safe water.

Do under-performing water utilities need to adapt to climate change? Experience from Eastern Europe and Central Asia.

Climate change raises particular challenges for under-performing water and sewerage utilities. A recent review for the World Bank explored some of the likely impacts of climate change on utilities in the Eastern Europe and Central Asian region. Climate change is likely to have serious implications for the regions water resources particularly because of the increasing incidence of severe precipitation events (floods and droughts). However the review found that the investment requirements needed simply to sustain service levels and reach remaining unserved customers may be a more pressing challenge. This finding is likely to be equally relevant in many other regions. The review concluded that: future investments should focus on systems which are as flexible and decentralized as possible; ongoing efforts to strengthen utility operations should not be abandoned; and greater investment should be made in technical training and capacity building to meet the challenges of the future

Carrying water may be a major contributor to disability from musculoskeletal disorders in low income countries: a cross-sectional survey in South Africa, Ghana and Vietnam

Background The Sustainable Development Goals include commitments to end poverty, and promote education for all, gender equality, the availability of water and decent work for all. An important constraint is the fact that each day, many millions of women and children, and much less frequently men, carry their household’s water home from off-plot sources. The burden of fetching water exacerbates gender inequality by keeping women out of education and paid employment. Despite speculation about the potential health impacts of fetching water, there is very little empirical evidence. We report the first large study of the health impacts of carrying water on women and children. Methods A cross-sectional survey was conducted in South Africa, Ghana and Vietnam during 2012. It investigated water carrying methods and health status. Because areas of self-reported pain were correlated we undertook factor analysis of sites of reported pain, to interpret patterns of pain reporting. Regression analysis using Generalised Estimating Equations (GEE) investigated water carrying as a risk factor for general health and self-reported pain. Results People who previously carried water had increased relative risk of reporting pain in the hands (risk ratio RR 3.62, 95% confidence interval CI 1.34 to 9.75) and upper back (RR 2.27, 95% CI 1.17 to 4.40), as did people who currently carry water (RR hand pain 3.11, 95% CI 1.34 to 7.23; RR upper back pain 2.16, 95% CI 1.25 to 3.73). The factor analysis results indicate that factor 1, ‘axial compression’, which is correlated with pain in the head and upper back, chest/ribs, hands, feet and abdomen/stomach, is associated with currently (0.30, 95% CI 0.17 to 0.43) or previously (0.21, 95% CI 0.01 to 0.42) carrying water. Factor 2, ‘soft tissue strain’, which is correlated with pain in the neck, shoulders/arms, lower back and hips/pelvis or legs, is marginally negatively associated with currently (-0.18, 95% CI -0.32 to -0.04) carrying water. The factor ‘axial compression’ was more strongly associated with carrying water containers on the head. Conclusions Participants who reported a history of current or past water carrying more frequently reported pain in locations most likely to be associated with sustained spinal axial compression in the cervical region. Given the fact that cervical spinal conditions are globally one of the more common causes of disability, our findings suggest that water carrying, especially by head loading is a major contributing factor in musculoskeletal disease burden in low income countries. Our findings support the proposed indicator for monitoring SDG6.1: “Percentage of population using safely managed drinking water services at home.”

Towards sustainable sanitation management: Establishing the costs and willingness to pay for emptying and transporting sludge in rural districts with high rates of access to latrines

Motivation Proper management of fecal sludge has significant positive health and environmental externalities. Most research on managing onsite sanitation so far either simulates the costs of, or the welfare effects from, managing sludge in situ in pit latrines. Thus, designing management strategies for onsite rural sanitation is challenging, because the actual costs of transporting sludge for treatment, and sources for financing these transport costs, are not well understood. Methods In this paper we calculate the actual cost of sludge management from onsite latrines, and identify the contributions that latrine owners are willing to make to finance the costs. A spreadsheet-based model is used to identify a cost-effective transport option, and to calculate the cost per household. Then a double-bound contingent valuation method is used to elicit from pit-latrine owners their willingness-to-pay to have sludge transported away. This methodology is employed for the case of a rural subdistrict in Bangladesh called Bhaluka, a unit of administration at which sludge management services are being piloted by the Government of Bangladesh. Results The typical sludge accumulation rate in Bhaluka is calculated at 0.11 liters/person/day and a typical latrine will need to be emptied approximately once every 3 to 4 years. The costs of emptying and transport are high; approximately USD 13 per emptying event (circa 14% of average monthly income); household contributions could cover around 47% of this cost. However, if costs were spread over time, the service would cost USD 4 per year per household, or USD 0.31 per month per household—comparable to current expenditures of rural households on telecommunications. Conclusion This is one of few research papers that brings the costs of waste management together with financing of that cost, to provide evidence for an implementable solution. This framework can be used to identify cost effective sludge management options and private contributions towards that cost in other (context-specific) administrative areas where onsite sanitation is widespread.

Policy review of the means of implementation targets and indicators for the sustainable development goal for water and sanitation

The Sustainable Development Goals, adopted by the Member States of the United Nations in September 2016, contain both ‘Outcome’ and ‘Means of Implementation’ targets. However, there is generally weak evidence linking the Means of Implementation to outcomes, they are imperfectly conceptualised and inconsistently formulated, and tracking their largely qualitative indicators will be difficult. In this paper, we analyse and critique the Means of Implementation targets of the Sustainable Development Goal on water and sanitation (SDG6). Improvements are recommended that would reflect: the considerable investment needed to attain SDG6; the important role of the state, including government leadership and planning; the utility of disaggregating financial and capacity-building assistance; and the need for people to realise their rights to information, voice and remedy. Recommendations are also made for relevant indicators, including indicators that are applicable to governments in both aid-providing and aid-receiving countries.

Effects of water source accessibility and reliability improvements on water consumption in eastern Nairobi

Under the commitments of the UN Sustainable Development targets, there is increasing pressure on water utility providers in developing countries to improve their levels of service to consumers, especially for the rapidly growing numbers of people with lower incomes who reside in urban informal settlements. However, pressure on water resources in many regions is simultaneously increasing owing to factors such as pollution, agricultural needs, and climate change. It is therefore important to assess the impacts of improving water services on city-wide water resources. This study examines consumption data from the East African city of Nairobi, collected from households of a variety of residential neighbourhoods. The study suggests that average per capita water consumption is closely related to water source choice (i.e. tap in the dwelling, yard tap, or water vendor kiosks). Within categories of water source type, variables such as household wealth, cost of water, and education do not have significant effects ...

Effect of filter media thickness on the performance of sand drying beds used for faecal sludge management

The effect of sand filter media thickness on the performance of faecal sludge (FS) drying beds was determined in terms of: dewatering time, contaminant load removal efficiency, solids generation rate, nutrient content and helminth eggs viability in the dried sludge. A mixture of ventilated improved pit latrine sludge and septage in the ratio 1:2 was dewatered using three pilot-scale sludge drying beds with sand media thicknesses of 150, 250 and 350 mm. Five dewatering cycles were conducted and monitored for each drying bed. Although the 150 mm filter had the shortest average dewatering time of 3.65 days followed by 250 mm and 350 mm filters with 3.83 and 4.02 days, respectively, there was no significant difference (p > 0.05) attributable to filter media thickness configurations. However, there was a significant difference for the percolate contaminant loads in the removal and recovery efficiency of suspended solids, total solids, total volatile solids, nitrogen species, total phosphorus, chemical oxygen demand, dissolved chemical oxygen demand and biochemical oxygen demand, with the highest removal efficiency for each parameter achieved by the 350 mm filter. There were also significant differences in the nutrient content (NPK) and helminth eggs viability of the solids generated by the tested filters. Filtering media configurations similar to 350 mm have the greatest potential for optimising nutrient recovery from FS.

Crowd-sourced data for geospatial sanitation planning in informal settlements

Crowd-sourced geospatial data from OpenStreetMap and the Map Kibera project were used to model and optimise a proposed road-based sanitation network for the settlement of Kibera in Nairobi, Kenya. A Boolean multicriteria suitability analysis was employed to identify areas of land for transfer station infrastructure construction. Selected locations were then used in a spatio-topological network model for a theoretical road-based faecal sludge management scheme to service 158 public toilets in Kibera using Vacutug technology. The network model was employed to further optimise the location of transfer stations based on minimising total sewage transport time across the network. In this manner the paper establishes the utility of maps generated by communities and citizens as providing vital on-the ground information for sanitation engineering planning. Such information is in lieu of traditional formal sources of geospatial data, which are often not available in informal settlements. The study demonstrates crowd-sourced maps, when combined with geographical information systems for analysis, present new opportunities for sanitation infrastructure provision planning in unplanned communities.

Adapting to climate change in Europe and Central Asia: background paper on water supply and sanitation

In general, the Europe and Central Asia Region (ECA) is predicted to become wetter and warmer as a result of climate change, with more frequent weather extremes (drought, floods, heatwaves, and winter squalls). While in general precipitation in the region is low, around 40 percent is converted to runoff – higher than in any other region. Changes in runoff patterns are likely to be significant across much of the region, with increases in much of the Russian Federation and decreases in most other sub-regions. Overall the outlook for the region is one of increasing uncertainty and extremes in weather events with northern areas becoming wetter and warmer and southern areas drier. This paper is written from the perspective of the utility manager or municipal and government planner. It examines the increasing risk and uncertainty facing utilities in the ECA region and explores some of the potential responses and resources available. It is based on a short literature review which draws on three broad bodies of literature: the first deals with climate change and adaptation in general and provides useful information about likely impacts in the ECA region and generalized policy responses; the second deals with adaptation in water utilities. This literature tends to have little explicit analysis pertaining to the ECA region; and the third examines the performance and operating options of utilities in the ECA region but which tends to have little explicit analysis on the impacts of climate change.