Observations on the hydrochemical groundwater situation of the Western Netherlands

Abstract

The western Netherlands encompasses a polder area with the land surface predominantly some tens of cm to several m below mean sea level. The history of salinization of this area has been and is governed by the geologic history, the reclamation history of the former lakes, and the hydrological groundwater situation. This has resulted in a complicated hydrochemical groundwater situation. The practical significance of studies like the one described is that processes in progress can be explained, that earlier situations can be reconstructed, and that a prediction of future situations can be made. At the start of the study only the chloride contents of the groundwater were taken into account; at a later stage other ions were included, and this gives a good conspectus of the hydrochemical groundwater situation of the area. Since in many parts of the area upward seepage occurs, the groundwater composition is of great importance for the composition of the open water.