Abbreviated Name:
Population using safely managed drinking-water services
Indicator Name:
Percentage of population using safely managed drinking-water services
Domain:
Health determinants and risks / Demographic and socioeconomic determinants
Related Terms:
Environmental health, communicable diseases
Definition:
Population drinking water from an improved source that is accessible on premises, available when needed and free from faecal and priority chemical contamination. Improved water sources include piped water, boreholes or tubewells, protected dug wells, protected springs, rainwater, and packaged or delivered water.
Measurment Method:
Data on improved drinking water facilities are routinely collected in household surveys and censuses. These data sources may also collect information on the location of water sources (e.g. on premises or off premises), as well as the amount of time that is required to go to the water point, collect water, and return to the household. Surveys may also ask respondents if they are able to get sufficient quantities of water when needed. Household-level responses, weighted by household size, are used to compute population coverage. Data on quality of drinking water services, including hours/days of service in piped systems and compliance with drinking water standards, are routinely collected by drinking water regulators, ministries, utilities, municipalities and other government institutions with authority for oversight of service delivery.
Numerator:
Population using safely managed drinking-water services
Denominator
Total population
Estimation method:
The JMP assembles, reviews and assesses national data collected by statistics offices and other relevant institutions including sectoral authorities. Linear regression is used to provide estimates of the population using improved drinking water sources, as well as the proportion with improved water supplies on premises. Regressions are also made to estimate the population using piped water supplies; this is constrained to not exceed the estimate for total improved drinking water sources. The proportion of the population using improved drinking water facilities that accesses those facilities with a collection time of thirty minutes or less is estimated by taking an average of all available data from household surveys and censuses. Separate regressions are made on three service level parameters: (1) the proportion of the population which drinks water from improved water sources which are accessible on premises, (2) the proportion of the population which drinks water from improved water sources which are available when needed (that is, households are able to access sufficient quantities of water when needed), and (3) the proportion of the population which drinks water from improved water sources which are compliant relevant national or local standards (for E. coli, and for arsenic and fluoride if available). In the absence of such standards, reference is made to the WHO Guidelines for Drinking Water Quality. Separate regressions are made for urban and rural areas. The most recent household survey or census available for most countries was typically conducted two to six years ago. The JMP extrapolates regressions for two years beyond the last available data point. Beyond this point the estimates remain unchanged for up to four years unless coverage is below 0.5 per cent or above 99.5 per cent, in which case the line is extended indefinitely. Since the data sources used for different service level parameters may not be the same, it is not always possible to determine which households or populations meet all three of the service level criteria. Instead, safely managed drinking water services are calculated at the urban and rural levels by taking the minimum of the three service level parameters. National estimates are generated as weighted averages of the urban and rural estimates, using population data from the most recent report of the United Nations Population Division. For more information see https://washdata.org/monitoring/methods/estimation-methods Predominant type of statistics: adjusted and predicted
Disaggregation:
Location (urban/rural)
Primary data sources:
Household surveys, population census
Alternate data sources:
Administrative reporting system
Measurment frequency:
Population based survey are implemented 3-5 years, estimation would be updated annually
