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 (regional and global).

This approach combines raster data containing layers on geology, hydrology, soil types, climate and land use with point measurements of fluoride or arsenic in groundwater to investigate the possible relationship between these parameters.

The results are depicted as risk maps showing the probability of fluoride/arsenic contamination in a certain region.

Below are some examples of our models for predicting groundwater quality in unmonitored areas:


Ling, Y.; Podgorski, J.; Sadiq, M.; Rasheed, H.; Eqani, S. A. M. A. S.; Berg, M. (2022) Monitoring and prediction of high fluoride concentrations in groundwater in Pakistan, Science of the Total Environment, 839, 156058 (9 pp.), doi:10.1016/j.scitotenv.2022.156058, Institutional Repository
Podgorski, J.; Berg, M. (2022) Global analysis and prediction of fluoride in groundwater, Nature Communications, 13(1), 4232 (9 pp.), doi:10.1038/s41467-022-31940-x, Institutional Repository
Araya, D.; Podgorski, J.; Berg, M. (2022) How widespread is fluoride contamination of Ghana's groundwater?, Water Science Policy, (4 pp.), doi:10.53014/OGJS9699, Institutional Repository
Araya, D.; Podgorski, J.; Kumi, M.; Mainoo, P. A.; Berg, M. (2022) Fluoride contamination of groundwater resources in Ghana: country-wide hazard modeling and estimated population at risk, Water Research, 212, 118083 (10 pp.), doi:10.1016/j.watres.2022.118083, Institutional Repository
Podgorski, J.; Araya, D.; Berg, M. (2022) Geogenic manganese and iron in groundwater of Southeast Asia and Bangladesh - machine learning spatial prediction modeling and comparison with arsenic, Science of the Total Environment, 833, 155131 (11 pp.), doi:10.1016/j.scitotenv.2022.155131, Institutional Repository
Alam, M. F.; Villholth, K. G.; Podgorski, J. (2021) Human arsenic exposure risk via crop consumption and global trade from groundwater-irrigated areas, Environmental Research Letters, 16(12), 124013 (18 pp.), doi:10.1088/1748-9326/ac34bb, Institutional Repository
Wu, R.; Podgorski, J.; Berg, M.; Polya, D. A. (2021) Geostatistical model of the spatial distribution of arsenic in groundwaters in Gujarat State, India, Environmental Geochemistry and Health, 43, 2649-2664, doi:10.1007/s10653-020-00655-7, Institutional Repository
Podgorski, J.; Berg, M. (2020) Global threat of arsenic in groundwater, Science, 368(6493), 845-850, doi:10.1126/science.aba1510, Institutional Repository
Wallis, I.; Prommer, H.; Berg, M.; Siade, A. J.; Sun, J.; Kipfer, R. (2020) The river-groundwater interface as a hotspot for arsenic release, Nature Geoscience, 13, 288-295, doi:10.1038/s41561-020-0557-6, Institutional Repository
Stopelli, E.; Duyen, V. T.; Mai, T. T.; Trang, P. T. K.; Viet, P. H.; Lightfoot, A.; Kipfer, R.; Schneider, M.; Eiche, E.; Kontny, A.; Neumann, T.; Glodowska, M.; Patzner, M.; Kappler, A.; Kleindienst, S.; Rathi, B.; Cirpka, O.; Bostick, B.; Prommer, H.; Winkel, L. H. E.; Berg, M. (2020) Spatial and temporal evolution of groundwater arsenic contamination in the Red River delta, Vietnam: interplay of mobilisation and retardation processes, Science of the Total Environment, 717, 137143 (13 pp.), doi:10.1016/j.scitotenv.2020.137143, Institutional Repository
Podgorski, J.; Berg, M.; Kipfer, R. (2019) Isotope mapping of groundwater pollution and renewal, IAEA Bulletin, 60(1), 31-32, Institutional Repository
Podgorski, J. E.; Labhasetwar, P.; Saha, D.; Berg, M. (2018) Prediction modeling and mapping of groundwater fluoride contamination throughout India, Environmental Science and Technology, 52(17), 9889-9898, doi:10.1021/acs.est.8b01679, Institutional Repository
Razanamahandry, L. C.; Andrianisa, H. A.; Karoui, H.; Podgorski, J.; Yacouba, H. (2018) Prediction model for cyanide soil pollution in artisanal gold mining area by using logistic regression, Catena, 162, 40-50, doi:10.1016/j.catena.2017.11.018, Institutional Repository
Bretzler, A.; Stolze, L.; Nikiema, J.; Lalanne, F.; Ghadiri, E.; Brennwald, M. S.; Rolle, M.; Schirmer, M. (2018) Hydrogeochemical and multi-tracer investigations of arsenic-affected aquifers in semi-arid West Africa, Geoscience Frontiers, 10(5), 1685-1699, doi:10.1016/j.gsf.2018.06.004, Institutional Repository
de Meyer, C. M. C.; Rodríguez, J. M.; Carpio, E. A.; García, P. A.; Stengel, C.; Berg, M. (2017) Arsenic, manganese and aluminum contamination in groundwater resources of Western Amazonia (Peru), Science of the Total Environment, 607, 1437-1450, doi:10.1016/j.scitotenv.2017.07.059, Institutional Repository
Bretzler, A.; Berg, M.; Winkel, L.; Amini, M.; Rodriguez-Lado, L.; Sovann, C.; Polya, D. A.; Johnson, A. (2017) Geostatistical modelling of arsenic hazard in groundwater, In: Bhattacharya, P.; Polya, D. A.; Jovanovic, D. (Eds.), Best practice guide on the control of arsenic in drinking water, 153-160, Institutional Repository
Podgorski, J. E.; Eqani, S. A. M. A. S.; Khanam, T.; Ullah, R.; Shen, H.; Berg, M. (2017) Extensive arsenic contamination in high-pH unconfined aquifers in the Indus Valley, Science Advances, 3(8), e1700935 (10 pp.), doi:10.1126/sciadv.1700935, Institutional Repository
Bretzler, A.; Lalanne, F.; Nikiema, J.; Podgorski, J.; Pfenninger, N.; Berg, M.; Schirmer, M. (2017) Groundwater arsenic contamination in Burkina Faso, West Africa: predicting and verifying regions at risk, Science of the Total Environment, 584, 958-970, doi:10.1016/j.scitotenv.2017.01.147, Institutional Repository
Rodríguez-Lado, L.; Sun, G.; Berg, M.; Zhang, Q.; Xue, H.; Zheng, Q.; Johnson, C. A. (2013) Groundwater arsenic contamination throughout China, Science, 341(6148), 866-868, doi:10.1126/science.1237484, Institutional Repository
Winkel, L. H. E.; Trang, P. T. K.; Lan, V. M.; Stengel, C.; Amini, M.; Ha, N. T.; Viet, P. H.; Berg, M. (2011) Arsenic pollution of groundwater in Vietnam exacerbated by deep aquifer exploitation for more than a century, Proceedings of the National Academy of Sciences of the United States of America PNAS, 108(4), 1246-1251, doi:10.1073/pnas.1011915108, Institutional Repository
Amini, M.; Abbaspour, K. C.; Berg, M.; Winkel, L.; Hug, S. J.; Hoehn, E.; Yang, H.; Johnson, C. A. (2008) Statistical modeling of global geogenic arsenic contamination in groundwater, Environmental Science and Technology, 42(10), 3669-3675, doi:10.1021/es702859e, Institutional Repository
Amini, M.; Mueller, K.; Abbaspour, K. C.; Rosenberg, T.; Afyuni, M.; Møller, K. N.; Sarr, M.; Johnson, C. A. (2008) Statistical modeling of global geogenic fluoride contamination in groundwaters, Environmental Science and Technology, 42(10), 3662-3668, doi:10.1021/es071958y, Institutional Repository
Winkel, L.; Berg, M.; Amini, M.; Hug, S. J.; Johnson, C. A. (2008) Predicting groundwater arsenic contamination in Southeast Asia from surface parameters, Nature Geoscience, 1, 536-542, doi:10.1038/ngeo254, Institutional Repository


Dr. Michael Berg Head of Department Tel. +41 58 765 5078 Send Mail

Geogenic Contamination Handbook

Launched on January 15th, 2015, this digital resource offers information and guidelines for practitioners dealing with arsenic- and fluoride-contaminated drinking water in developing countries.