The global water quality database GEMStat
The Global Water Quality database and information system GEMStat is hosted, operated, and maintained by the International Centre for Water Resources and Global Change (ICWRGC) in Koblenz, Germany, within the framework of the GEMS/Water Programme of the United Nations Environment Programme (UNEP), and in cooperation with the Federal Institute of Hydrology. GEMStat hosts water quality data of ground and surface waters providing a global overview of the condition of water bodies and the trends at global, regional and local levels.
At present, the growing database contains around 26 million entries for rivers, lakes, reservoirs, wetlands and groundwater systems from 91 countries and close to 30,000 stations. Overall, data is available for the time period from 1906 to 2025 and 659 parameters (see data section for more information).
Countries and organisations voluntarily provide water quality data from their own monitoring networks. The water quality data available in GEMStat can be used for status evaluation, policy-making, research purposes or within the scope of education and training initiatives.
Download our flyer with all relevant
information on GEMStat:
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The GEMS/Water-Programme
The Global Environment Monitoring System for Freshwater (GEMS/Water) is a programme that aims at collecting world-wide freshwater quality data to support scientific assessments and decision-making processes. In addition, GEMS/Water offers support and encouragement to developing countries wishing to establish monitoring programmes and conduct assessments of water quality, by providing capacity development via training, advice and assessment tools.
GEMS/Water was established in 1978 as an interagency programme under the auspices of the United Nations through the United Nations Environment Programme (UNEP), the World Health Organization (WHO), the World Meteorological Organization (WMO), and the United Nations Educational, Scientific and Cultural Organization (UNESCO). Until 2014, when it returned to UNEP, the programme has been implemented by the WHO at the National Water Research Institute (NWRI) in Burlington, Canada.
With the adoption of the Sustainable Development Goals (SDGs) and especially SDG 6 (“Clean Water and Sanitation”), the importance of water quality for human and ecosystem health has attracted renewed attention. In June 2014, the first UN Environment Assembly (UNEA) in Nairobi (Kenya) endorsed GEMS/Water as being one of the mechanisms to assist in achieving the SDGs. Special focus is on sub-target 6.3, aiming at improving water quality, and the corresponding indicator 6.3.2.
Collected in the GEMStat database, the data of GEMS/Water were managed by the Department of the Environment of Canada for more than 30 years, until March 2014. Since November 2014, GEMStat has been operated, hosted and maintained by the GEMS/Water Data Centre (GWDC) within the International Centre for Water Resources and Global Change (ICWRGC) in Koblenz, Germany.
Explore the objectives, elements and recent activities of GEMS/Water in an interactive Story Map:
Today the GEMS/Water Programme comprises the following elements:
Data Centre, Germany
Global Programme Coordination Unit, Kenya
- Global Programme Coordination Unit (GPCU):
Located in the Science Division at the UNEP headquarters in Nairobi, Kenya, the GPCU is responsible for the overall coordination of the GEMS/Water Programme and the maintenance of the GEMS/Water network of National and Collaborating Focal Points (NFPs and CFPs). Furthermore, it works with Regional Hubs and partners on designing water quality monitoring schemes, capacity development and assessments as well as providing services for policy making and water management.
https://www.unep.org/topics/fresh-water/water-quality/monitoring-water-quality
https://communities.unep.org/display/gemswater
- GEMS/Water Data Centre (GWDC):
Based on a treaty between UNEP and the German Federal Ministry for the Environment, Climate Action, Nature Conservation and Nuclear Safety, the GWDC is located at the International Centre for Water Resources and Global Change (ICWRGC) in Koblenz. The GWDC hosts, maintains and coordinates the GEMStat database and information system. It also disseminates activities related to GEMStat data.
