CRMGG supports KIT with land subsidence measurements during pump tests

Researchers from the former BMBF-funded research ViWaT Engineering project are currently investigating the correlation between groundwater depletion and land subsidence in the southern Mekong Delta in a unique pilot site experiment. The hydraulic heads in three aquifers at depths of 100, 150 and 250 m will be deliberately lowered for 12 days each. In addition to the hydraulic evaluation of these pump tests, the spatial and temporal evolution of local subsidence due to the induced groundwater depletion will be evaluated by two methods. The first method is the so-called Land Subsidence Observatory (LSO), installed by the ViWaT Engineering group in Dec 2022, which allows a high-resolution, depth-differentiated assessment of compaction processes in the different sediment layers. The second method is a series of geodetic monitoring rounds during the pumping activities that serve to verify the LSO data and allow a spatial assessment of the area affected by the pumping. CRMGG financially supports the geodetic monitoring campaign and is in regular exchange with the researchers.

KIT researchers Felix Dörr and Tran Viet Hoan with the geodetic team from GEOTEX (photo: Felix Dörr)

Lowering the pumps into the well for the first pump test (photo: Felix Dörr)

Geodetic levelling at the site (photo: Felix Dörr)