Forests protect drinking water: Drought threatens our water resources!

Forests protect drinking water: Drought threatens our water resources!

In Germany, forests are essential for the quality of drinking water and the protection of water resources. Currently, 43 percent of water protection areas are forested, and a third of German forests are already designated as water protection areas. These areas play a crucial role because the majority of drinking water in Germany comes from groundwater that is obtained in these protected areas. The strict rules that apply there help to minimize contamination risks and ensure the safety of the water. How uni-freiburg.de reports, healthy forests are essential for drinking water quality.

An important element in this context is the role of forests in reducing nitrate concentrations in groundwater. Fungi and microorganisms in the forest floor actively process the water chemically and can often make it usable as drinking water without costly purification. One hectare of forest can retain up to two million liters of water, while the forest floor can store up to 50 liters of rainwater per square meter. In forested watersheds, the nitrate concentration in groundwater is significantly lower than in the open landscape forstwirtschaft-in-deutschland.de emphasized.

Danger of forest dieback

Threats such as droughts have a direct impact on forests and thus on drinking water quality. Researchers have found that within three years of the start of the 2018 drought, five percent of forested areas in water protection areas had already died. Forests with a high proportion of spruce trees and beech trees in particular recorded high losses. In areas where forest loss was over 25 percent, nitrate concentrations increased from 5 mg/l (2008-2017) to 11 mg/l (2021-2022). In contrast, no elevated nitrate levels were found in areas with less than 3 percent forest loss. The reasons for these differences could be varied forest types or time lags between forest loss and nitrate increase, according to information from uni-freiburg.de.

In order to counteract the further deterioration in forest health, the BUND calls for careful handling of forests. These are not only important for drinking water quality, but also store water and mitigate the effects of drought and heavy rain. A new forest law should ensure the prioritization of the protection and restoration of healthy forests as well as the consideration of ecosystem services in forestry, such as bund.net highlights.

Future prospects

The planned amendment to the Federal Forest Act, which is due to be passed in the Bundestag in summer 2024, will also take into account requirements for wildlife management and requirements for the protection of mixed deciduous forests. Support for private forest owners who provide ecosystem services to the public is also sought. Only through this holistic approach can the valuable functions of forests for the water balance and drinking water quality in Germany be secured in the long term.