Proportion of the population with access to improved sanitation refers to the percentage of the population with access to facilities that hygienically separate human excreta from human, animal and insect contact. Facilities such as sewers or septic tanks, poor-flush latrines and simple pit or ventilated improved pit latrines are assumed to be adequate, provided that they are not public, according to the World Health Organization (WHO) and United Nations Children’s Fund’s (UNICEF) Global Water Supply and Sanitation Assessment 2000 Report. To be effective, facilities must be correctly constructed and properly maintained.
Goal 7. Ensure environmental sustainability.
Target 10. Halve, by 2015, the proportion of people without sustainable access to safe drinking water and basic sanitation.
Good sanitation is important for urban and rural populations, but the risks are greater in urban areas where it is more difficult to avoid contact with waste.
Method of computation
The indicator is computed as the ratio of the number of people in urban or rural areas with access to improved excreta-disposal facilities to the total urban or rural population, expressed as a percentage.
Data collection and source
Since the late 1990s, data have routinely been collected at national and subnational levels in more than 100 countries using censuses and surveys by national governments, often with support from international development agencies. Two data sources are common: administrative or infrastructure data that report on new and existing facilities, and data from household surveys including Multiple Indicator Cluster Surveys, Demographic and Health Surveys and Living Standard Measurement Surveys. Before these population-based data were available, provider-based data were used.
Evidence suggests that data from surveys are more reliable than the administrative records and provide information on facilities actually used by the population.
Rural and urban population statistics come directly from population censuses.
Global Water Supply and Sanitation Assessment 2000 Report, World Health Organization and United Nations Children’s Fund (www.who.int/water_sanitation_health/Globassessment).
Indicators of Sustainable Development: Guidelines and Methodologies, 2001, United Nations Division for Sustainable Development (www.un.org/esa/sustdev/natlinfo/indicators/isd.htm).
World Health Organization, www.who.org.
Periodicity of measurement
Administrative data are often available annually. Household surveys are generally conducted every three to five years. The WHO and UNICEF annually compile international data and prepare regional and global estimates based on household survey data.
Women and men usually have different roles in water and sanitation activities. These differences are particularly pronounced in rural areas. Women are most often the users, providers and managers of water in rural households and the guardians of household hygiene. If a water system breaks down, women are more likely to be affected than men because they have to travel further for water or use other means to meet the household’s water and sanitation needs.
The indicator should be monitored separately for urban and rural areas. Because of national differences in characteristics that distinguish urban from rural areas, the distinction between urban and rural population is not amenable to a single definition applicable to all countries. National definitions are most commonly based on size of locality, with rural population as the residual of population that is not considered urban.
International data comparisons
World Development Indicators, annual, World Bank (www.worldbank.org/data).
United Nation’s Children’s Fund, www.childinfo.org and www.unicef.org.
Demographic and Health Surveys, www.measuredhs.com.
Living Standards Measurement Study, www.worldbank.com/lsms.
World Health Organization, www3.who.int/whosis.
Comments and limitations
When data are from administrative sources, they generally refer to existing sanitation facilities, whether used or not. Household survey data are therefore generally better than administrative data, since survey data are based on actual use of facilities by the surveyed population rather than the simple existence of the facilities.
While access is the most reasonable indicator for sanitation facilities, it still involves severe methodological and practical problems. Among them:
The definition of access to improved sanitation facilities and methods for assessing it are even more contentious than those for water, with national definitions of “acceptable” sanitation varying widely.
National statistical offices.
United Nations Children’s Fund.
World Health Organization.