DeltAs

Access to clean and safe drinking water is a human right – yet millions of people worldwide still lack reliable access to it. One major threat is the toxic metal arsenic. Water contamination by arsenic endangers millions of people worldwide. Regions that are severely affected are the Red River and Mekong Delta in Vietnam. The arsenic concentration in the groundwater in these deltas exceeds the maximum levels set by the WHO, which are considered safe. Prolonged exposure to arsenic-contaminated drinking water can result in serious health effects, including organ damage and cancer.

The high levels of arsenic contamination in Vietnams delta regions are of natural origin. However, the spread of the contamination is continuously changing, driven by human activities such as groundwater pumping and natural events like floods. As environmental conditions and affected zones are subject to continuous change, the reliable identification of safe drinking water sources remains a significant challenge.

The DeltAs project investigates how arsenic contamination of groundwater evolves over time in the Red River and Mekong Deltas. To date, only limited research has examined how the extent of contamination, as well as its underlying causes, changes over time. Based on the analysis of these processes, the project additionally aims to evaluate how climatic changes and human activities may influence arsenic levels in the future. The data collected can serve as a foundation for policy decisions, to help ensure the supply of safe drinking water in the region.

To achieve this goal, researchers from Switzerland, Vietnam, the United States, and Australia are working together. The team combines expertise in earth observation, hydrogeology, and geochemistry.

The UZH team, comprisingAlexander Damm, Anh Minh Vu, and Pauline Enguehard, contributes its expertise from the field of Earth Observation (EO). With the help of EO data, they are investigating the dynamics of river sediment transport and sediment deposition. River sediment is the source of As in the delta regions and it deposition or erosion provides interesting information on the availability of this substance. The team also quantifies the surface water balance in the deltas using various EO data sources to gain insight in the amount of water available for infiltration. Derived information is then combined with models and tools from project partners to better understand As contamination patterns.

Funding

Swiss National Science Foundation (SNSF), Sinergia grant

Time frame

February 2024 – January 2028

Contact

Alexander Damm

Principal investigators

Alexander Damm (Co-PI,UZH, Switzerland) 

Philippe Renard (Co-PI,University of Neuchatel, Switzerland)

Lenny Winkel (PI, ETH & Eawag, Switzerland)

Athena Nghiem (University of Wisconsin-Madison, United States)

Pham Hung Viet (VNU University of Science, Vietnam)

Duong Hong Anh (VNU University of Science, Vietnam)

Tong Ngoc Thanh (National Center for Water Resources Planning and Investigation, Vietnam)

Duong Du Bui (National Center for Water Resources Planning and Investigation, Vietnam)

Michael Berg (Eawag, Switzerland)

PostDocs

Pauline Enguehard (University of Zurich, Switzerland)

Michael McGlade (ETH Zurich/Eawag, Switzerland)

Ludovic Schorpp (University of Neuchatel, Switzerland)

PhD students

Anh Minh Vu (University of Zurich, Switzerland)

Juyong Bak (University of Wisconsin-Madison, USA)

Nina Egli (University of Neuchatel, Switzerland)

Further collaborators

Son Nghiem (NASA Jet Propulsion Laboratory, United States)

Quang-Khai Ha (Ho Chi Minh City University of Technology, Vietnam)

Henning Prommer (University of Western Australia, Australia)