Vertical Wetlands
Urban rivers and canals have lost their natural shorelines and shallow water zones, replaced by steep concrete, steel, or masonry banks. This rigidity deprives the shores of essential habitats for many plants and animals. To address this issue, the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) and its partners have developed “Vertical Wetlands.” These planting modules serve as ecological stepping stones in artificial waters, allowing fish and other species to stay and migrate.
Benefits of Vertical Wetlands
These Vertical Wetlands are particularly effective in areas where renaturation is impossible due to intensive use or dense development. They offer key ecological solutions that reduce environmental deficits even on small surfaces. They allow for quick and cost-effective improvement of water sections while contributing to water quality by reducing heat input from sun-heated banks. Additionally, they enhance the visual aspect of urban banks.
How do Vertical Wetlands work?
The technical design and implementation of the pilot system were entrusted to the Berlin engineering firm WITE GmbH. The system consists of a support rail attached to the bank wall and planting modules hung from it. It can be installed on sheet pile walls, natural stone, or concrete walls and uses only water-safe and biodegradable materials: untreated steel, rough-sawn wood, sand or gravel, biodegradable fleece, and typical wetland vegetation such as willows, alders, reeds, rushes, and cattails. Ecologically valuable deadwood can also be attached to the modules.
This system is highly flexible, able to be installed at different heights, lengths, and angles, whether from land or water, thus meeting various site constraints. It can also be easily dismantled if necessary. The Vertical Wetlands are designed to withstand strong currents, ship-induced suction, and waves. In case of significant damage, the modules can be individually replaced without much effort.
Pilot System Berlin
A 40-meter-long pilot system was installed in the Berlin-Spandau navigation canal, consisting of 76 planting modules with reeds and four types of willows. Installed in April 2023 over 14 days from a floating work platform, this project quickly showed positive results. Fish eggs were found on the modules a few days after installation, and coots began nesting within weeks. After one month, roots had developed, providing valuable refuges for fish and supporting their migration through urban waterways. The modules were also colonized by other aquatic plants, mosses, algae, and various insects.
To facilitate the rapid replication of this success, the team published a free “IGB Manual” explaining the construction and approval procedures for Vertical Wetlands. This manual contains conceptual drawings and an implementation plan based on the pilot project’s experiences. The goal of this publication is to raise awareness of this approach, encourage its imitation, and allow interested parties to assess the feasibility of installing Vertical Wetlands elsewhere.
The pilot project was funded by the Berlin Program for Sustainable Development (BENE) of the European Regional Development Fund (ERDF) and the State of Berlin, with support from the Waterways and Shipping Office, the Senate Department for Mobility, Transport, Climate Protection, and the Environment, and the Mitte district. Dr. Christian Wolter expressed his gratitude for the constructive cooperation of all involved partners.
