In the process of establishing a system for the assessment of the risk of drying using benthic invertebrate communities, we will first focus on common features of benthic communities inhabiting intermittent and permanent streams on the one hand, and differences between them on the other. We will look for indicators of drying and, on the other hand, indicators of permanent flow. These indicators may be at the taxonomic of functional (trait) level (e.g. a high proportion of long-lived macroinvertebrates indicates that drought has not occurred recently). Subsequently, we will test the indicators’ reliability at an independent data set, select the best indicators and incorporate them in a resulting multimetric index. Finally, this index is expected to be able to assess, at some accuracy level, how much a watercourse is vulnerable to drying and how much its macroinvertebrate community is affected by drought.