BRIEF November 14, 2018

Frequently Asked Questions: "Promising Progress: A Diagnostic of Water Supply, Sanitation, Hygiene, and Poverty" Report

1.       What is the focus of the “Promising Progress:  A Diagnostic of Water Supply, Sanitation, Hygiene, and Poverty in Bangladesh” report?

The ‘Promising Progress:  A Diagnostic of Water Supply, Sanitation, Hygiene, and Poverty in Bangladesh’ report is a data-driven exercise that assessed the population’s access to water, sanitation, and hygiene (WASH). It also highlighted key service delivery gaps within the WASH sector, particularly focusing on the bottom 40 percent of the population. This research is a part of the World Bank’s WASH Poverty Diagnostics initiative in 18 countries, including Bangladesh.

The diagnostic produced three broad categories of outputs:

a.       Maps and disaggregated statistics on WASH coverage trends within sub-national populations and areas;

b.       Econometric analyses on the synergies of WASH and human development; and

c.       Institutional analysis on WASH service delivery challenges.

By sharing WASH related statistics and identifying service delivery gaps, the report aims to support the policymakers and practitioners design WASH policies and operations to meet WASH related Sustainable Development Goals.

2. What are the key findings of the report, “Promising Progress: A Diagnostic of Water Supply, Sanitation, Hygiene, and Poverty in Bangladesh?”

In South Asia, Bangladesh stands out for its progress in the WASH sector. About 98 percent of people drink water from a technologically improved water source. The country has also eliminated the practice of open defecation and about 63 percent people use improved sanitation facilities. But, much has yet to be done, especially in areas of improving the quality of WASH services and closing inequities in access between rich and poor populations.  

The study identified the following key service delivery gaps:

·         Providing drinking water free of fecal and chemical contamination;

·         Ensuring safe sanitation and fecal sludge management;

·         Improving population hygiene practices; and

·         Expanding WASH coverage to public places, such as schools, health facilities, and workplaces.

Poor water quality and sanitation can hold back a country’s potential because unsafe water and poor sanitation are linked to nutritional disadvantages in early childhood. Bangladesh can build on its progress on expanding access to water by focusing on improving the quality of water, sanitation, and hygiene. 

3. The report says that despite near-universal access to improved water sources, 41 percent of all improved water sources are contaminated with E. coli bacteria. Please specify what type of improved water sources are included in this analysis.

Despite the country’s remarkable progress, 41 percent of all improved water sources are contaminated with E. Coli bacteria, which suggests a high prevalence of fecal contamination.  While poor drinking water quality affects the rich and poor alike, but the poorest quintile of the population suffers three times more from water and sanitation related gastro-intestinal diseases.

The study follows the definitions of improved water sources and water quality guidelines as per guidance from the World Health Organization and UNICEF Joint Monitoring Programme (JMP), which is the official UN mechanism for monitoring global progress in meeting WASH targets outlined in SDG-6 for water.

As Per JMP definitions, “an ‘improved’ drinking water source is one that, by the nature of its construction and when properly used, adequately protects the source from outside contamination, particularly fecal matter.” They include: piped water, boreholes or tube wells, protected dug wells, rainwater, protected springs and packaged or delivered water.

JMP also offers guidance on water quality parameters in priority bacterial and chemical contaminants, including E. coli, arsenic, and fluoride. JMP defines E. coli contamination when there is more than 1 coliform forming unit (cfu) per 100 milliliters of water. The study found that 41% of all improved water sources across Bangladesh were contaminated with E. coli as per the JMP definition.

The findings on water quality of this report are consistent with global and regional research that show that having access to improved drinking water sources alone cannot consistently guarantee safe drinking water.

4. The report finds that E. coli bacteria was present in 82% of piped-to-premise water. What does piped-to-premise water mean?

Piped-to-premise or on-premise piped water means that a household is accessing tap water located at their household premises. The study estimates that about 7 percent of the national population has access to on-premise water.

Bangladesh’s water sector faces a complex set of challenges including water quality. Public taps have a 55 percent E. coli contamination rate, while on-premise piped water taps have an 82 percent E. coli contamination rate. In comparison, 38 percent of samples taken from tube wells, 55 percent of samples taken from public piped taps, and 83 percent of samples taken from unimproved surface water sources such as rivers/ponds were found to be contaminated with E. coli.

However, the rate of contamination can vary by region—factors such as population and farm animal density, frequency of flooding, leakages in piped systems due to improper installations, low water pressure, and intermittent supply can affect the microbial water quality—but almost everywhere the rates were very high. The scope of the report did not include identifying causes of contamination. E. coli bacteria can generate anywhere from source point to the tap, including water tanks and pipes within the house, if not properly maintained. Understanding the reasons for the contamination is one of the biggest knowledge gaps of WASH programs in Bangladesh.

5. What is the methodology you used for estimating water quality? How large was the sample size and what were the areas covered?

For this study, the World Bank analyzed the 2013 Multiple Indicator Survey (MICS) by UNICEF and the Bangladesh Bureau of Statistics (BBS). With a sample size of 55,120 households, the 2013 MICS is the only nationally-representative household survey that collects water quality parameters on E. coli and arsenic in Bangladesh. The 2013 MICS took representative sub-samples and tested E. coli in 2,588 households and arsenic in 12,952 households. The sampling strategy allows for water quality estimates to be representative at the national, urban, rural, and sub-national boundary levels.

The World Bank was not involved in collecting the water quality data, but accessed the raw data provided by UNICEF and made estimations. The World Bank estimates were cross-checked and closely match the estimates provided in the original survey reports.

The water quality analysis is limited in the following ways:

·         It cannot disaggregate the data with adequate statistical certainty to determine where different types of water sources are most contaminated;

·         It cannot identify the exact service providers that households are using for drinking water;

·         It cannot identify the causes of contamination;

·         It cannot account for seasonality differences since samples were collected at one point-in-time; and

·         Finally, data on water quality was collected in 2013 and does not reflect any changes over the last 5 years. However, from experience, gradual improvements in water quality happen over long periods of time.

6. What can Bangladesh do to reduce E. coli bacteria contamination in drinking water?

As an immediate response, the households need to safely store, handle, and treat water before drinking. Evidence shows that point-of-use water treatment is among the most effective WASH interventions for reducing fecal exposure and diarrheal disease. Boiling, filtration, and chlorination are proven methods for reducing fecal contamination, yet only 10% of households report treating their water.

In the medium to long-term, policies, research, and operations should be designed to better monitor contamination levels, identify causes of contamination, and implement solutions to improve water quality.

7. Besides E. coli bacteria, what are the pollutants present in the drinking water?

Arsenic contamination remains a problem in some parts of the country: about 13 percent of improved water is contaminated with above 50 parts per billion arsenic (Bangladesh government standard), while about 26 percent WPD is contaminated with above 10 parts per billion arsenic (WHO standard). The vast majority of arsenic contamination comes from tube wells, and Chittagong and Sylhet divisions suffer the most. Salinity intrusion in drinking water is also a noted problem in coastal areas.

8. By improving WASH, how will Bangladesh reduce poverty faster?

WASH can play a catalyzing role in improving human development outcomes and reducing poverty. Better WASH can reduce harmful environmental exposures that cause an array of health conditions. Poor water quality and sanitation is linked with nutritional disadvantages in early childhood. Bangladesh can expand on its success of near-universal access to water and can build on that progress by focusing on improving the quality of water and sanitation.

The report urges to improve WASH beyond its traditional sector boundaries. WASH improves public health but also facilitates, directly and indirectly, other development and poverty reduction goals, such as increasing educational attainment, reducing stunting, and creating a healthy and skilled work force.


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