6.3.2 Proportion of bodies of water with good ambient water quality (Tier II)
This indicator is conceptually clear, has an established methodology and builds on international standards. Supported by the methodology previously developed by GEMS/Water based on a global water quality indicator, which allows countries to monitor and report according to
- their respective capacities,
- step-wise improve monitoring,
- indicator reporting coverage as capacities evolve.
The indicator tracks the percentage of water bodies in a country with good ambient water quality. “Good” indicates an ambient water quality that does not damage ecosystem function and human health according to core ambient water quality parameters and is set at the national level. This includes through in situ monitoring of 5 core parameters:
- dissolved oxygen (surface water)
- electrical conductivity (surface water and groundwater)
- nitrogen/nitrate (surface water and groundwater)
- phosphorus (surface water)
- pH (surface water and groundwater)
The Global Environment Monitoring Systems supports the collection of in situ data on water quality. As European countries already report through the EEA under the European Water Framework Directive there is a current effort to ensure alignment in order to reduce the reporting burden.