HYDRA investigates possible impacts of climate change on groundwater augmentation, which is a major component of Berlin’s drinking water production. The project is about to figure out to what extent varying surface water discharge may lead to restricted use of groundwater augmentation in the future. Another focus of the project is to determine the impact of increasing temperatures on the hydraulic performance of groundwater augmentation during infiltration and subsurface passage until abstraction.

Groundwater augmentation is a major component of Berlin’s drinking water production. The BMUB-funded project HYDRA aims at analysing quantitative effects of groundwater augmentation. The project contributes to Berlin’s climate change strategy and “Masterplan Water” by recommendations related to climate change adaptation.

The following questions are to be answered in HYDRA:

• Which operational control and adaptation options are available to cope with a potential limited use of groundwater augmentation in times of insufficient availability of surface waters?

• What are the impacts of rising water temperatures, low surface water levels and expected higher nutrient entries on the surface water treatment, in particular the clogging behaviour in the infiltration ponds?

• How do rising water temperatures affect the hydraulic properties of groundwater recharge?

• With which simple and cost-effective methods can hydraulic boundary conditions be monitored online?

• What are the impacts of surface water extraction for groundwater augmentation under different climate-related scenarios on the local water balance?

The HYDRA Project in the “Actions Data Base” of the German Federal Environment Agency