More than a quarter of humanity relies on drinking water from karst aquifers. Since precipitation quickly infiltrates the karst body, there are hardly any storage possibilities at the surface. In the Dong Van Karst Plateau in northern Vietnam, the tropical climate with pronounced dry seasons leads to existential supply shortages. Since September 2010, the project area has been a UNESCO Geopark; therefore, tourism will increasingly develop there and further aggravate the water supply problem. During a first project phase, numerous hydrogeological investigations were carried out. Our focus was on characterizing and quantifying the existing water resources. Based on climate data, as well as geological and hydrogeological mapping, a conceptual hydrogeological model was created and validated by numerous marking tests.

Within the framework of KaWaTech solutions, the variability of hydrochemical and microbiological parameters is investigated in detail at several surface waters and springs used for drinking water supply. As a result of heavy rainfall events, an increased input of pathogenic microorganisms and suspended particles can be observed. These affect water quality and severely limit its use. In order to avoid contamination of the drinking water and to minimize the abrasion risk for the pumps used for drinking water supply, the establishment of an early warning system is planned. The particle size distribution in the project region during the dry periods as well as the rainy season will be used as a basis for this. Vulnerability mapping will be used to assess the vulnerability of the water resources used and a groundwater protection concept will be developed from this.

Commissioning of the Seo Ho water extraction system in March 2019 by the KaWaTech team under the leadership of the IWG.