Many urban riverbanks are technically optimised but ecologically impoverished. Smooth habitat structures, steep edges and a lack of varying depths characterise the landscape. What works for vertical bank stabilisation offers little biological value. There is a lack of a living transition zone between land and water – with its microhabitats, refuges and structured settlement areas. This is precisely where the SpundwandQuartier comes in: it supplements existing structures with functional, 3D-printed habitat modules and transforms monotonous hard substrates into vibrant ecological spaces – without significantly affecting the supporting infrastructure. In doing so, the SpundwandQuartier does not view technical bank structures as ecological barriers, but rather as previously untapped areas of potential. It bridges the gap between civil engineering and ecosystem development – in a modular, compatible and scientifically supported manner.
Retrofitting rather than new construction
The modules are manufactured using Shotcrete 3D Printing (SC3DP), an additive manufacturing technique employing concrete specially formulated to meet the requirements, and are suspended within existing habitat structure troughs. The existing structure remains largely unaffected structurally. This results in a technically compatible solution that can be integrated into existing port and water infrastructure and is significantly easier to implement in terms of planning permission than structural redesigns. The system has a modular design and, thanks to its customisable design, enables a gradual ecological enhancement – tailored to the specific location, scalable and economically viable.
Structure creates life
In the underwater area, the blue module forms a finely detailed shelving structure with planes at varying angles of inclination. This creates varied surface, flow and light conditions that can be tailored to selected target organisms. Initial trials and comparable studies on structured hard substrates suggest that biofilms form on the surfaces within a short time. In the days that follow, colonisation by algae and microorganisms is to be expected; subsequently, larger invertebrates such as crustaceans or molluscs may also settle there. Whether and to what extent stable communities of organisms develop as a result, and which ecological functions – such as filtration or local improvements in light and oxygen conditions – are actually achieved, is the subject of ongoing scientific investigation.
Above the waterline, the green module extends the ecological impact into the transition zone between water and land. It creates space for flood-tolerant marsh and riparian plants, thereby promoting the connectivity of aquatic and terrestrial habitats. In addition to its ecological function, it also creates a visibly enhanced riverside landscape, which increases acceptance and adds value for the local community.
Contribution to European environmental objectives
By functionally complementing existing hard substrates, the SpundwandQuartier supports the objectives of the EU Water Framework Directive to improve the ecological status of surface waters. At the same time, it contributes to the implementation of the EU Biodiversity Strategy in urban areas.
Pilot project in urban water bodies
An initial prototype of the SpundwandQuartier was developed as part of the ‘Future Urban Coastlines’ project. It was manufactured and funded by the Technical University of Braunschweig. In collaboration with the Lebensraum Elbe Foundation, its deployment in Hamburg’s waterways – including the Bille area – is being coordinated and scientifically monitored. What begins as a controlled colonisation experiment for animals and plants on a 3D-printed hard concrete substrate is intended to form the basis for a transferable model for the ecological restoration of urban waterways. The aim is to systematically document the development of biofilms, invertebrates, plants and other groups of organisms, and to derive reliable findings from this for the use of structured artificial substrates in an urban context.