Resources and Downloads

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Groundwater Assessment Platform (GAP) flyer

Over 300 million people worldwide use groundwater as a source of drinking water that contains natural contaminants, (e.g. arsenic or Fuoride). The Swiss Federal Institute for Aquatic Science and Technology (Eawag) applies statistical and machine learning methods to estimate the risk of geogenic contamination using geological, topographical and further environmental data without having to test all groundwater wells. Corresponding risk maps of safe and unsafe groundwater were produced at regional to global scales....

December 04, 2019


Groundwater Assessment Platform (GAP) fact sheet

Over 300 million people worldwide use groundwater as a source of drinking water that is naturally contaminated with arsenic or fluoride. The Swiss Federal Institute of Aquatic Sciences and Technology (Eawag) has developed a methodology whereby the risk of contamination in a given area can be estimated using available geological, topographical and other environmental data without having to test groundwater sources....

January 06, 2020

Geogenic Contamination Handbook

December 04, 2019

This digital resource offers information and guidelines for practitioners dealing with arsenic- and fluoride-contaminated drinking water in developing countries.

The handbook was revised and updated in June 2017. Download the updated version below.

Note: because the handbook includes many embedded documents, it is a very large file (42 MB)! Individual chapters can be downloaded below. In addition, an online version of the handbook without embedded files is available via the Wiki page of....


GAP brochure

Groundwater serves as drinking water for around 50% of the world’s population and is indispensable for irrigation and food production in many regions. Over-abstraction, pollution and changing climatic patterns are all factors leading to groundwater stress. In terms of drinking water quality, groundwater is usually less affected by pathogens than surface water. However, naturally occurring (geogenic) contaminants such as arsenic and fluoride affect many aquifers, with serious long-term health effects for those consuming the water....

December 04, 2019


Risk Maps

The regional or national assessment of groundwater quality is vital when planning to exploit groundwater for drinking purposes. Especially in developing countries, detailed surveys on groundwater quality are often lacking or incomplete. Therefore, there is a demand for tools capable of assessing groundwater quality on larger scales, for example, to identify hot-spots for geogenic contamination. Using GIS methods, it is possible to model the probability of groundwater being contaminated by arsenic or fluoride on large scales....

December 04, 2019


Water Resource Quality

Water Resource Quality (WRQ) was an integrated project running from 2006-2012 at Eawag that aimed to develop a generally applicable framework for the mitigation of geogenic contamination in groundwater used for drinking, in particular concerning arsenic and fluoride. We combined natural and social scientific expertise for the solution of a health problem that affects 100s of millions of people worldwide. The mitigation framework developed by the WRQ team from Eawag can help decision-makers and water resource managers to identify contaminated regions and to provide feasible options to help reduce the effects of contamination....

December 04, 2019


Groundwater Pollution Red River Delta/Vietnam

Inorganic arsenic and manganese are the most widespread elemental contaminants of potable water around the world. Being mainly of natural (geogenic) origin, arsenic and manganese are released from sediments in the subsurface as a result of unfavourable geochemical conditions and can occur in groundwater at concentrations of more than 1000 micrograms per litre of water. The safety limits for arsenic in drinking water in most countries are 10 or 50 and, for manganese 400 micrograms per litre (µg/litre)....

December 04, 2019

Water GIS Info Contact