Animproved water source (orimproved drinking-water source orimproved water supply) is a term used to categorize certain types or levels ofwater supply for monitoring purposes. It is defined as a type of water source that, by nature of its construction or through active intervention, is likely to be protected from outside contamination, in particular from contamination withfecal matter.[1]
The term was coined by theJoint Monitoring Program (JMP) for Water Supply and Sanitation ofUNICEF andWHO in 2002 to help monitor the progress towards Goal Number 7 of theMillennium Development Goals (MDGs). The opposite of "improved water source" has been termed "unimproved water source" in the JMP definitions.
The same terms are used to monitor progress towardsSustainable Development Goal 6 (Target 6.1, Indicator 6.1.1) from 2015 onwards.[2] Here, they are a component of the definition for "safely managed drinking water service".
Indicator 6.1.1 of SDG 6 is "Proportion of population using safely managed drinking water services". The term "safely managed drinking water services" is defined as: "Drinking water from an improved water source that is located on premises, available when needed and free from fecal and priority chemical contamination".[2]
In 2017, the JMP defined a new term: "basic water service". This is defined as the drinking water coming from an improved source, and provided the collection time is not more than 30 minutes for a round trip. A lower level of service is now called "limited water service" which is the same as basic service but the collection time is longer than 30 minutes.[2]
Service levels are defined as (from lowest to highest):Surface water, unimproved, limited, basic, safely managed.[2]
| JMP Drinking water ladder | |
|---|---|
| Safely Managed | |
| Basic | |
| Limited | |
| Unimproved | |
| Surface Water | |
| source | |
To allow for international comparability of estimates for monitoring theMillennium Development Goals (MDGs), theWorld Health Organization/UNICEFJoint Monitoring Program (JMP) for Water Supply and Sanitation defines"improved" drinking water sources as follows:
Water sources that are not considered as "improved" are:
