ViWaT - Vietnam Water Technologies

Grundwasser und Aquiferdynamik Technical surface water allocation, storage and water quality

Achievements after three years:

  • Feasibility study for the use of alternative water resources
  • Developing concepts for water storage


Groundwater table depletion and subsequent land subsidence is largely caused by overexploitation
of groundwater resources of various aquifers. Only the stop of groundwater extraction is able to stop
the land subsidence, but alternative water resources have to be offered from either rain, Mekong,
local rivers and canals or coastal waters. Furthermore, drought periods of the recent parts
highlighted the needs for sufficient capacities of stored water resources. Phase 1 has to be used to
identify and elaborate the sustainable concepts to meet these needs and to outline necessary
technological measures that shall be implemented in phase 2.

Groundwater table depletion caused by operating thousands of wells is accompanied by salinization
processes and land subsidence due to compaction in the underground. However, in most cases there
is no metering of the water quantity that is abstracted.
The groundwater system in Ca Mau is fairly complex and groundwater recharge, land
subsidence and salinization processes are not well understood yet. Automatic monitoring
technologies for groundwater wells is not available for NAWAPI, only manual records of
temperature, water table and electrical conductivity exist, far too less to lay out a sustainable groundwater
management concept. Therefore, six groundwater monitoring wells are planned to be implemented and
equipped with state of the art online and in-situ monitoring systems. Similar, four online and in-situ
monitoring systems shall observe surface water dynamics. Areas in need of fast action will be identified and determined which measures have to be implemented to make surface water usable for
public needs. Finally, ground and remote sensing shall unveil spatial heterogeneities of land
subsidence.

 

Figure1: Operational steps and correlations in WP4