Discrepancies between National and International Data on Improved Drinking Water and Sanitation : Bangladesh Experience By A Y M Ekamul Hoque Director General Bangladesh Bureau of Statistics

1.Introduction : Among the Eight Millennium Development Goals (MDG) Goal -7 is “Ensuring Environmental Sustainability”. This goal has two targets of which target no- 2 (Target 10 of MDG Targets) is to halve by 2015 the proportion of people without sustainable access to safe drinking water and sanitation. This target has two important indicators. These are as follows:

2.Concept and Definition used in Bangladesh: Indicator 7.8 : Proportion of population using an improved drinking water source Indicator 7.9 : Proportion of population using improved sanitation facility. The variation with respect to national and international data on improved drinking water source and sanitation system occurs mainly due to concept and definition used in the Censuses and Surveys.

The concepts and definition used in different census and surveys varies in the context of Bangladesh particularly in case of sanitation facility. In case of drinking water the definition used in the multiple indicator cluster survey (MICS) conducted by UNICEF and BBS, 2006 is as follows: 2.Concept and Definition used in Bangladesh (cont.):

Improved Drinking water: “The population using improved sources of drinking water are those with any of the following types of water supply: piped water (into dwelling yard or plot), public tap/standpipe, tube well/borehole, protected well, protected spring and rain water collection. Bottled water is considered as an improved water source only if the household is using it for other purpose also such as hand washing and cooking”.

Improved Sanitation: The MICS 2006 used the following sanitation facilities as improved: flash toilet connected to sewerage system, septic tanks and pit latrines, ventilated improved pit latrines and pit latrine with slabs and composting toilets.

3.Arsenic contamination in tube well water: In the recent year, arsenic contamination of ground water remains as a significant issue for Bangladesh. The level of arsenic that has been considered as unsafe in the context of Bangladesh is 0.05 mg/l. MICS survey was conducted in July-September 2006 when the testing of all tube wells for arsenic contamination was not completed. However, MICS survey asked the households whether their tube well was tested for arsenic.

Table I: Tube wells tested/marked for arsenic contamination, 2006 Residence Tube wells Tested for Arsenic Total Not tested Tested/ma rked red Tested marked green Missi ng National Rural Urban Division Barisal Chittagong Dhaka Khulna Rajshahi Sylhet Source: MICS- 2006, Volume 1: Technical Report, page-55

3. Arsenic contamination in tube well water (cont.) In response around 62% reported that their tube wells were tested for arsenic contamination and the rest 38% mentioned that their tube well was not tested for arsenic contamination. The MICS 2006 report mentioned 97.6% households with improved source of drinking water which did not consider arsenic contamination. If arsenic contamination is considered the percentage of improved source will be less.

4. Data on drinking water obtained from BBS and MDG website. Table-2 below shows data obtained from the MDG website and that has been supplied by BBS. It may be noted that the data supplied by BBS has not been adjusted for arsenic contamination. Therefore, the variation in the two sources are well pronounced. Table 2 : Improved Drinking water sorce, Bangladesh Data source MDG web site BBS

But if we look at the table – 1 where 8% households were reported that their tube well was marked red and 38% mentioned that their tube well was not tested for arsenic contamination. The same table also showed that in Chittagong Division more than 17% households reported that their tube well was arsenic contaminated. So at the national level after completing the test of all households, the rate will be higher than 8%. The arsenic contamination adjusted rate of 80% in 2006 seems logical because the contamination is increasing over the year due to fall in ground water level. Therefore, the difference in MDG website data and BBS data is due to adjustment of arsenic contamination. 4. Data on drinking water obtained from BBS and MDG website (cont.)

Improved sanitation The definition of improved sanitation as used in MICS-2006 is same as the definition used in MDG in light of UNICEF, but this definition is not strictly followed in other Censuses and Surveys of Bangladesh Data supplied by BBS for MDG indicator is taken from Sample Vital Registration System (SVRS) of BBS. This source has been used as annual data is available from this survey. But this surveys used more lenient definition than MICS. Thus, the estimates are higher than MICS. Table-3 shows improved sanitation coverage from MICS-2006.

Table-3 Improved sanitation coverage from MICS Type of toilet facility used by Households Improved sanitation facility Unimproved sanitation facility Residence Flush to piped sewer system Flush to septic tank Flush to pit (latrin e) Pit latrine with slabs Pit latrine without slab/ open pit Hangi ng toilet/ Hangi ng latrine No toilet facilit y or bush or field Oth er Total National Urban Rural Improved sanitation

Table 4: Improved Sanitation coverage by Residence 1991 to Year Sanitation Coverage NationalRuralUrban Source: SVRS 1991 to Improved sanitation

The above table indicate that there exist variation in sanitation coverage over the year. Data used for 2001 is taken from population Census 2001 It may be mentioned that the sample size of SVRS was increased from 2000 and the estimates from the subsequent year is based on large sample of 1000 PSU (more than 200,000 households) Therefore, the estimates of later year are different from earlier years However, the situation improved over the years. Therefore, the estimates of later year are different from earlier years However, the situation improved over the years. It may be recalled that in SVRS the sanitary latrine has been defined as those latrine where the enumerators considered it as sanitary. Improved sanitation

The water sealed and non-water sealed pit latrine or even open pit were considered as sanitary latrine. This made the coverage rate higher than the MICS, where MICS followed global definition. The sanitation data used in MDG report is almost similar to MICS but not the same. It is not clear what is the data source of MDG indicators. Improved sanitation

Table 5: Improved sanitation coverage by source. SourceNationalUrbanRural MDG website MICS-2006, BBS Table 5 shows the MDG indicator 7.9 on Sanitation coverage in Bangladesh obtained from MDG website. It is observed from the above table that sanitation coverage in Bangladesh is still much lower than the excepted outcome.

Conclusion: Data discrepancy between BBS data and that of MDG website is mainly due to definitional variation. As regards improved drinking water, the arsenic free drinking water will be less than the improved drinking water sources mentioned in our data. On the other hand, data on improved sanitation depends as the definition considered for the improved sanitation source.