A more ecosystem-based approach to the management of floodplains would help to conserve and restore biodiversity and reduce chemical and nutrient pollution in rivers, lakes and wetlands, and increase water retention according to the EEA report ‘Floodplains: a natural system to preserve and restore.’ Such an approach would recognise the multiple functions floodplains play.
Natural, undisturbed floodplains are under increased pressure from human development, putting at risk the unique environmental roles they play during flood cycles. The report points to studies that show that up to 90 % of floodplains have been environmentally degraded as a result of structural flood protection, river straightening, disconnection of floodplain wetlands, agricultural land use and urbanisation over the past two centuries.
This degradation has put floodplains in a poor position to adequately provide important ecosystem services that could otherwise handle the increased risk of flooding due to climate change, as well as improve water and biodiversity status. While historical changes have supported economic growth and flood protection, they have had serious environmental consequences. Urban and agricultural development of floodplains together with structural flood protection have contributed greatly to disconnecting rivers from their floodplains, reducing their critical roles in flood and drought mitigation, as habitats, and in water quality protection. These changes have also made today’s floods more damaging.
Floods remain one of the most costly natural disasters. The report highlights that floodplain restoration — focused on nature based solutions and an ecosystem management approach — has the potential to greatly increase the role these areas can play in achieving positive environmental benefits, while also reducing the negative impacts of floods. Further, floodplains that are maintained in their natural condition would support objectives under existing European Union legislation, including the Water Framework, Floods, Birds and Habitats Directives. Restoring and preserving floodplains can also support the objectives of the European Green Deal, including climate change, tackling biodiversity loss and eliminating pollution.
Floodplains cover 7 % of Europe’s total area and up to 30 % of protected Natura2000 sites. While they are home to multiple protected species and habitats, they are also home to 12 % of Europe’s population and many of Europe’s cities. For example, more than 25 % of the population in Liechtenstein, Bosnia and Herzegovina, the Netherlands and Slovakia live in floodplain areas. Important ecosystem services they provide include natural water retention, carbon sequestration, water purification, habitats and biodiversity and recreation. In degraded floodplains, the quality of these services is reduced. Presently only 17% of Europe’s protected habitats associated with floodplains achieve good conservation station, and 40% of Europe’s water bodies achieve good ecological status. Enhancing the ecosystem services provided by floodplains could improve these results.