Well and pumping tests can be used to determine geohydrological parameters such as the permeability and storage coefficient of an aquifer, as well as the hydraulic resistance to vertical flow through a low-permeability layer.
In a pumping test, water is extracted from one or more aquifers by means of one or more wells. During pumping and for some time afterwards, the changes in hydraulic head are measured, in as many points as possible at various distances from the pumping well. The measurements recorded in the different pumping and monitoring filters are used in (model) calculations to determine geohydrological properties of the subsurface.
A well test is a simplified version of a pumping test in which only the hydraulic head in the pumping well or in the well's casing is recorded during pumping.
Tests of this kind have been carried out for a long time in the Netherlands. The first test reports available on DINOloket date from the early 20th century, the latest from early this century. This also means that there is a lot of difference in reliability and quality of the calculated geohydrological properties. At the beginning of the 20th century, measurements, flow rates, data processing and calculations were done manually while nowadays observations are automatically recorded and processed and the various geohydrological properties are calculated using special software applications.
Besides processing the measurements and performing the calculations, a good understanding of the subsurface is also very important. At present, more information about the subsurface is available and existing subsurface models can be used. As a result, insights may have changed and the outcome of historical well and pumping tests may no longer be fully comparable. In cooperation with Dr Henk Kooij (Deltares) the Geological Survey of the Netherlands has investigated the usability of permeability determinations from historical well and pumping tests for REGIS II. The results of this research have been published in the paper “Bruikbaarheid van doorlatendheidsbepalingen uit historische put- en pompproeven voor REGIS II” (in Dutch) in the journal Stromingen (2022-1) of the Dutch Hydrological Society as well as in the report “Bruikbaarheid van resultaten uit put- en pompproefrapporten voor REGIS II parametrisatie” (in Dutch).
Well and pumping tests on the map
For the reasons described above, the complete well and pumping test reports are made available instead of just the geohydrological parameters calculated from these tests. In this way, it can be deduced from the report to what extent it is relevant in the context of the current investigation.
An initial set of over 500 well and pumping test reports is available on DINOloket under Subsurface Data / Subsurface research. It will be supplemented over time with several existing and new well and pumping test reports.
Do you also have well and pumping tests?
If your organisation has historical or current well and pumping test reports that you want to share with others via DINOloket, you can submit them to the Service Desk of the Geological Survey of the Netherlands. This way, they can be consulted via DINOloket and help improve our understanding of the composition of the Dutch subsurface and the subsurface models we make with this information.