River (non)revitalization: when the human-altered watercourse can be a better choice

The outcomes of watercourse revitalization are mostly evaluated as positive, depending on the implementation of the given revitalization. A potential negative aspect of watercourse revitalization was investigated via the example of an important source of groundwater for drinking purposes in Březová nad Svitavou. The aim of the research was to assess whether revitalization of the watercourse in the section upstream of the offtake point was appropriate. The assessment used long-term data from the watercourse operator as well as our own short-term monitoring. The results indicate that in this section, the risk of contamination from surface water into groundwater significantly outweighs other benefits of revitalization. Therefore, a partial, modified revitalization was proposed, which in the assessed section maintains and regenerates the existing separation between the watercourse and the groundwater. At the same time, however, it enables the formation of river sediment in the trough as a natural environment for the development of zoo- and phytobenthos and related higher organisms.