Changes in Water Source Cause Shifts in Invertebrate Biomass, Composition, and Regrowth in a Non-Chlorinated Drinking Water Distribution System

Invertebrates such as Asellus aquaticus, halacarid mites, copepods and cladocerans are common in drinking water distribution systems. The Zeeuws-Vlaanderen system (DWDS) of Evides company is divided into western eastern sections, initially supplied with derived from a eutrophic reservoir (water) groundwater, respectively. was characterised less biologically stable than the groundwater. Due to groundwater level protection measures, since 2015 supply section has been gradually replaced treatment plant, which uses source water. This change caused increased regrowth conditions, observed by regulated microbial indicators (HPC22 Aeromonas), invertebrate biomass, dominant occurrence confirming observations other DWDSs. results same biological water, however, showed that regrowth, biomass A. aquaticus not only related stability but also influence DWDS-specific conditions. DWDS configuration well higher demands summer (western section) and/or sediment Fe accumulation (eastern suggested factors affecting therefore subjects for further research.