Historic low water levels across the Rhine, Danube and Po are intensifying concerns about the effects of climate change on Europe’s economy, agriculture, ecosystems and drinking water supplies. Following severe heatwaves and wildfires earlier in the summer, prolonged drought has caused European rivers to shrink dramatically, disrupting transportation and exposing riverbeds that are normally submerged.
The Rhine and Danube are particularly important for transporting goods across the continent. Falling water levels have prevented some cargo and cruise ships from navigating sections of the Danube, while vessels operating on German waterways are carrying as little as one-fifth of their normal loads. These restrictions are delaying deliveries and increasing costs for industries including steel, chemicals and petroleum. Agriculture is also suffering as drought damages crops, raising concerns that poor harvests could contribute to higher food prices.
Low water levels are creating serious ecological problems as well. As rivers become shallower, their temperatures rise and dissolved oxygen concentrations can decline, placing fish and other aquatic species under stress. Gravel banks along the Rhine that provide habitats for mussels and invertebrates are drying out. Meanwhile, drought, strong sunlight and nutrients from agricultural fertilizers can encourage harmful algal blooms. Similar conditions contributed to an ecological disaster on the Oder River in 2022, when toxic algae spread and approximately 1,000 metric tons of fish died.
The deterioration of European rivers could also have consequences for drinking water. In Germany, riverbank filtration plays an important role in supplying clean water. Water passing through riverbanks and soil is naturally filtered before reaching underground wells. During droughts, however, reduced river flows can increase pollutant concentrations because wastewater from industry and sewage treatment continues entering waterways while less water is available to dilute it.
Damage to natural filtration systems could therefore require more artificial treatment. German industry groups estimate that climate change could increase water supply costs by as much as 30%. By 2035, as much as €14 billion in additional investment could be required for treatment facilities, deeper water mains and improved reservoirs. Some cities are already restricting private withdrawals from waterways to conserve supplies.
Energy infrastructure is another concern. Low Danube levels have threatened cooling-water supplies for nuclear power stations in Hungary and Romania, demonstrating how drought can affect electricity generation as well as transportation and agriculture.
Governments are considering several ways to make European rivers and the industries dependent on them more resilient. Proposed measures include deeper navigation channels, low-water cargo vessels and transferring more freight to rail. However, critics argue that extensive dredging could accelerate water loss, reduce groundwater levels and damage floodplains.
Long-term solutions could instead involve restoring natural river systems. Reconnecting floodplains, protecting wetlands and restoring peatlands could allow landscapes to retain more water during droughts. Reservoirs may also provide additional protection where environmentally appropriate. Ultimately, experts argue that adapting European rivers to increasingly severe drought will need to be combined with rapid reductions in greenhouse gas emissions, because adaptation alone cannot eliminate the growing risks associated with continued global warming.
https://www.dw.com/en/europes-rivers-are-drying-up-can-they-be-saved/a-78276662