The overarching theme of the Sustainable Development Goal (SDG) 6 is to ensure that clean water and sanitation is available for all. SDG indicator 6.6.1, in particular, is meant to track changes in the extent of different types of water-related ecosystems including mountains, forests, wetlands, rivers, aquifers and lakes, enabling decision makers to determine in turn the extent of freshwater ecosystem changes over time. 

In 2017, the United Nations Environment Program (UNEP) requested all member states to provide data to report on national SDG indicator 6.6.1. This global data collection effort revealed that less than 20% of member states were able to report on the changing extent of their freshwater ecosystems. 

The Global Surface Water Explorer (GSWE), developed at that time by JRC scientists, proved to be very effective in addressing this knowledge gap. The GSWE, a virtual time machine that maps the location and temporal distribution of water surfaces at the global scale and provides statistics on their extent and change over time, was therefore accepted by the UN Expert Group on SDG indicators as reference dataset for the Indicator 6.6.1. 

The evidence produced and the derived indicators support countries in the reporting and enable more informed decisions towards the SDGs objectives.  

Using the GSWE and other complementary layers, such as the Copernicus Global Land’s Lake Water Quality product, UNEP, in partnership with Google and the JRC, developed the Freshwater Ecosystems Explorer (FEE), which uses Earth Observation to document further the water-related ecosystems changes over time. FEE  is a data platform providing , high-resolution, up-to-date geospatial data on freshwater ecosystems changes over time; it delivers interactive maps alongside measurements on freshwater quality and quantity at the national, sub-national and basin levels. This data is intended to drive action to protect and restore freshwater ecosystems. UN member states are using FEE to review national data before UNEP officially reports these statistics to the UN’s Statistical Division. 

Related material/further reading 

• Explore the Global Surface Water Explorer (GSWE) 

• Explore the Freshwater Ecosystems Explorer (FEE) 

• Atlas of Global Surface Water Dynamics 

• Position paper on water, energy, food and ecosystems (WEFE) nexus and sustainable development goals (SDGs) (Technical report by JRC, 06/06/2019); 

• Knowledge generation using satellite earth observations to support sustainable development goals (SDG): A use case on Land degradation