There are multiple sources of threats to freshwater molluscs in Europe. In the majority of cases there is no single source of threats to each species, but usually a series of threats combined that lead to declining populations. In general, most threatened species are suffering as a consequence of declining water quality in freshwater rivers and lakes, which is a problem throughout Europe, mainly due to intensification of agriculture (affecting 36% of the species) and urbanisation (poor sewage control, impacting 29% of the species). The other major threat comes from the over-utilization of water which impacts 33% of freshwater species. By contrast, although invasive species are present, and have had an impact on some species, in general it is not a significant factor and impacts less than 5% of the threatened species. The major threats for the future are the increased frequency and intensity of droughts. Springs are already seeing declines in recharge during summer drought events.