The canal as an aesthetic enhancement of the area.
First, the canal was completed in the section between the Mittellandkanal and Karl-Rüter-Straße. In 2014, a draft design for the basin design and water treatment facilities of a structurally separate southern extension of the canal was presented. The focus of the planning was mainly directed to the following objectives:
- The design is made similar to the previous canal
- Generation of an appealing water quality
- Use of the canal as a rainwater retention basin
- Integration to the drainage concept
- Minimization and simplification of the maintenance effort
The width of the canal and the design of the banks were to be based on the previously completed canal basins to ensure a consistent overall aesthetic impression. To enable the sediments to be cleared by machine if necessary, interlocking pavements were planned as the surface layer and a gravel base layer was planned as the foundation.
Water treatment
To prevent the Lister Gracht from reaching a highly eutrophic state in the long term, a submerged soil filter with a downstream hydrobotanical area was integrated into the basin. On one hand, organic substances and algae are degraded by the biofilm in the soil filter system, and on the other hand, phosphorus related to the trophic process is removed by adsorption. In the hydrobotanical system, dissolved phosphorus and other nutrients not captured by the filter can be taken up by submerged macrophytes (underwater plants). In addition to the filter systems, a bank planting with reeds was implemented to stabilize the water quality and to visually enhance the basin.
