July's exceptionally heavy rainfall caused particular issues across Luxembourg, as communities and authorities alike struggled to bounce back from the flooding. Many municipalities experienced a decline in water quality as a result.
Luc Zwank, deputy director at the water management authority, told RTL that heavy rain activates different drainage paths for the water, which in turn reduces the filtering effect of soil and rock layers. This allows unfiltered water to enter the springs and results in more bacteria.
What does this mean for the Grand Duchy's drinking water? George Kraus, director of the syndicate for Esch-sur-Sûre waters (Sebes), explained that they were able to react quickly in July, and were prepared for future catastrophes in a similar vein. Kraus said that some water sources were taken out of service immediately in the event of heavy rain. In such cases, Sebes bumps up its production to supply additional water. During the July floods, production was increased by 20-30%.
The immense rain mass this year has not necessarily had a direct effect on Luxembourg's groundwater levels, however. These reserves are typically only replenished in autumn and winter, when the rain cannot be fully absorbed by vegetation, instead sinking directly into the soil. Contrary to popular belief, heavy rain falls only superficially and normally does not penetrate the ground.
Despite this, Zwank said it was likely that the reserves will be replenished earlier this autumn than in previous years, due to high humidity levels at present.
Due to the steady growth of the economy and the Grand Duchy's population, more and more people will have to be supplied with clean water in the coming years.
Whether groundwater levels can recover on a constant cyclical basis, despite growth and climate change, remains unpredictable.
