What is the difference between safely managed and basic drinking water?
Short answer
Safely managed water comes from an improved source on the premises that is available when needed and free from fecal and priority chemical contamination. Basic water comes from an improved source where a round trip to collect it, including queuing, takes 30 minutes or less. In 2024, 73.7% of people worldwide used safely managed water and 91.5% used at least basic water, per World Bank data citing JMP.
The two levels differ in where the water comes from and how long it takes to collect. The WHO and UNICEF Joint Monitoring Programme (JMP) for Water Supply, Sanitation and Hygiene sets the definitions, which form the drinking water service ladder used to compare countries.
What are the JMP drinking water service levels?
Improved sources are those that, by their design and construction, have the potential to deliver safe water. They include piped water, boreholes or tubewells, protected dug wells, protected springs, rainwater, and packaged or delivered water. The JMP divides the population using improved sources into three service levels. The table quotes the JMP wording, which uses the British spelling "faecal".
| Rung | JMP definition |
|---|---|
| Safely managed | Drinking water from an improved water source that is accessible on premises, available when needed and free from faecal and priority chemical contamination |
| Basic | Drinking water from an improved source, provided collection time is not more than 30 minutes for a roundtrip including queuing |
| Limited | Drinking water from an improved source for which collection time exceeds 30 minutes for a roundtrip including queuing |
| Unimproved | Drinking water from an unprotected dug well or unprotected spring |
| Surface water | Drinking water directly from a river, dam, lake, pond, stream, canal or irrigation canal |
How do I classify a household's drinking water service?
Apply the tests in order:
- If the source is not improved, the household is unimproved or uses surface water.
- If the source is improved and is on the premises, available when needed and free from contamination, the household is safely managed.
- If the source is improved but fails any of those three tests, the round trip sets the level. Thirty minutes or less is basic, and more than 30 minutes is limited.
A protected well 25 minutes away is basic at best, even if its water is always available and tests clean, because it is not on the premises. A yard tap that runs only two days a week is basic, because it is not always available when needed.
Why is contamination the hardest test to answer?
The on-premises and availability tests can be answered by a household survey. The contamination test needs water samples, and testing covers only part of the sources in any survey. Read a country's safely managed figure with that in mind.
What do the World Bank water figures show for 2024?
The World Development Indicators (WDI) publish two JMP-based series for the world, labelled as citing JMP. The values below were retrieved on 2026-10-09:
SH.H2O.SMDW.ZS, people using safely managed drinking water services, % of population. World, 2024: 73.7%.SH.H2O.BASW.ZS, people using at least basic drinking water services, % of population. World, 2024: 91.5%. The 2025 value is blank, so 2024 is the latest year.
The basic series is "at least basic", so it includes the safely managed population. For the world in 2024:
- Safely managed: 73.7%
- Basic, but not safely managed: 91.5% − 73.7% = 17.8 percentage points
- Below basic (limited, unimproved and surface water): 100% − 91.5% = 8.5%
What does a worked drinking water example look like?
Take a fictional country of 10 million people, with 60% safely managed, 25% basic but not safely managed, and 15% below basic. The 60% is 6,000,000 people, and at least basic service is 85%, or 8,500,000 people. The remaining 1,500,000 people use limited, unimproved or surface water.
How do I calculate service levels in a spreadsheet?
Put one country per row, with the population in column B, the safely managed share in column C and the at-least-basic share in column D. Enter the shares as percentages such as 73.7 and 91.5, not as fractions. Keep the year beside each value, because the latest year differs by country.
- Basic only, E2:
=D2-C2 - Below basic, F2:
=100-D2 - People using safely managed water, G2:
=B2*C2/100 - People using at least basic water, H2:
=B2*D2/100 - Input check, I2:
=IF(C2>D2,"check inputs","ok")
For the world row, E2 returns 17.8 and F2 returns 8.5. The check in I2 should always read "ok".
The drinking water and sanitation access by country workbook holds these indicators for each country. The freshwater withdrawals by country workbook answers a different question, how much water countries take from rivers, lakes and aquifers. It does not measure access to safe drinking water.