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Issue Profile

Water and Sanitation

Water and Sanitation tracks percentage of population with access to improved drinking water sources and improved sanitation, including pit latrines and toilets.

What it Measures: This category includes two indicators: Access to Drinking Water and Access to Sanitation. Access to Drinking Water measures the proportion of a country’s total population with access to an “improved drinking water source” as a main source of drinking water. An improved drinking water source is defined as a facility or delivery point that protects water from external contamination—particularly fecal contamination. This includes piped water into a dwelling, plot, or yard; public tap or standpipe; tubewell or borehole; protected spring; and rainwater collection.

Access to Sanitation measures the percentage of a country’s population that has access to an improved source of sanitation. “Improved” sanitation sources include connection to a public sewer, connection to a septic system, pour-flush latrine, simple pit latrine, or ventilated pit latrine. The system is considered “improved” if it hygienically separates human excreta from human contact and is not public, meaning that it can neither be private or shared.

Why we include it: Access to Drinking Water is the best currently available proxy for access to clean drinking water. Access to reliable, safe water reduces exposure to pollution, disease, and harmful contaminants, thereby promoting health and wellbeing. For example, diarrhea is the leading cause of death among children, and is directly caused by consumption of contaminated water. Access to Sanitation is vital for maintaining healthy drinking water supplies, minimizing contact with dangerous bacteria and viruses, and minimizing environmental threats associated with improper waste management.

Where the data come from: 2012 WHO/United Nations Children’s Fund (UNICEF) Joint Monitoring Programme for Water Supply and Sanitation (JMP).

What the targets are: 100% for Access to Drinking Water; 100% for Access to Sanitation. For more information click here

Description: In 2010, the United Nations (UN) formally acknowledged that clean drinking water and sanitation are essential to the realization of human rights. Access to safe drinking water is a critical component to human health, socioeconomic development, and individual wellbeing. Improved access to safe drinking water is often considered one of the great successes of the MDGs set of eight international development goals established following the Millennium Summit of the UN in 2000. Between 1990 and 2010, more than two billion people gained access to improved drinking water sources. As a result, the MDG of halving the proportion of people without access to improved sources of water was met in 2010—a full five years ahead of schedule.

However, this global progress can easily mask broad regional disparities. While China and India have made great progress in improving access to drinking water, only 63 percent of the population in Sub-Saharan Africa has access to an improved water source. Additionally, within countries there are often stark disparities between urban and rural communities. At the end of 2011, 83 percent of the population without access to an improved drinking water source lived in rural areas. Globally, 768 million people continue to rely on unimproved drinking water sources

While the world has made great strides in increasing access to improved drinking water sources, only 55 percent of the global population has access to piped drinking water. This has both social and public health implications, as piped drinking water supplies on premises are associated with the best health outcomes, and minimize the disproportionate burden placed on women and children to retrieve water. Additionally, improving global access to sanitation has been slow. UNICEF estimates that approximately 2.5 billion people worldwide still lack access to adequate sanitation, and 15 percent of the world’s population is forced to defecate in the open. These one billion people are primarily (71 percent) rural. In sub-Saharan Africa the number of people practicing open defecation continues to grow. (See World Toilet Day Raises Awareness for Access to Sanitation

The combination of inadequate access to safe drinking water and sanitation kills and sickens thousands of children every day. Inadequate sanitation further impacts quality of life for millions of people, extending beyond public health by exacerbating gender inequality issues and stunting economic development. Data from the WHO and UNICEF indicate that it is the poorest, the young and the elderly, excluded groups, and women and girls who suffer most from poor sanitation.

The quality of the datasets that make up these indicators is considered robust. The JMP, which has made improvements to its methods, is a success story in coordinated international data collection. Prior to 1990, the WHO relied on self-reported data provided by country agencies and ministries of health to assess the global status of water supply and sanitation. By the late 1990s the limitations of self-reported data became clear, as definitions of access to water and sanitation varied both between and within countries. As the official UN mechanism tasked with monitoring progress towards the MDGs related to drinking water and sanitation, the JMP, beginning in 2000, made improvements in data collection, data standardization, and reporting. Today, the JMP estimates are derived from user-based data from nationally representative household surveys. Provider-based data is only used when no other source is available. The number of national surveys available to the JMP has increased over the years, and currently includes over 1,400 national datasets, the majority of which are nationally representative household surveys and censuses. 

While these datasets are robust, they do not comprehensively address concerns relating water to environmental and public health outcomes. Key information missing from the Access to Water dataset includes whether water is priced affordably (a factor for access), or whether the quality of water is actually safe for consumption. For example, naturally occurring arsenic in groundwater affects nearly 140 million people worldwide who rely on “improved” drinking water sources. Additionally, while providing adequate sanitation and access to improved drinking water minimizes the risk of coming into contact with dangerous bacteria and viruses, it is important to note that the dataset that informs the Access to Sanitation indicator does not measure what proportion of waste is treated before it is released back into the environment. Untreated sewage pollutes freshwater sources and ocean ecosystems and puts human health at risk. To address this deficiency we have introduced a new indicator on wastewater treatment in the Ecosystem Vitality component of the overall 2014 EPI. (See Issue Profile: Water Resources.)

As the 2015 expiration date for the MDG draws closer, there is considerable interest within the UN to continue to work toward universal access to clean drinking water and sanitation through the elaboration of a Sustainable Development Goal (SDG) for water. An SDG for water currently being proposed through this UN process would continue and extend goals for access to clean drinking water and sanitation for developing countries. It would also apply universal targets for developed countries, since the developed world still has water management gaps that have yet to be addressed. While much progress has been made to improve access to sanitation and drinking water worldwide, there are still millions of individuals that lack this basic human right.

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The Environmental Performance Index (EPI) is constructed through the calculation and aggregation of 20 indicators reflecting national-level environmental data. These indicators are combined into nine issue categories, each of which fit under one of two overarching objectives. Click on "Learn More" to explore the complete methods.