1. General information
2. Objectives of the intervention
Goals of the intervention
-Improving the water quality of the Aa stream (Ref. 1 and 4)
-Reestablishing the ecological balance of the Aa lake as an important recreational area for the citizens of Münster (Ref. 4)
-Reducing blue algae bloom and silting in the Aa lake (Ref. 3)
-Increase the biodiversity in the water bodies and along the river banks (Ref. 4)
-Reestablishing the ecological balance of the Aa lake as an important recreational area for the citizens of Münster (Ref. 4)
-Reducing blue algae bloom and silting in the Aa lake (Ref. 3)
-Increase the biodiversity in the water bodies and along the river banks (Ref. 4)
Quantitative targets
Renaturalizing a 2,4 km stretch of the Aa stream between Sentruper Street and its river mouth in the Aa lake (Ref. 1)
Monitoring indicators defined
Water quality, number of animals and plants species in the water body and riverbanks ecosystems, amount of algae, river flow velocity (Ref 1-4)
Sustainability challenge(s) addressed
Climate change adaptation: What were the goals of the NBS?
Climate change adaptation: What activities are implemented to realize the conservation goals and targets?
Habitats and biodiversity conservation: What types of conservation goals are / were defined for the NBS intervention?
Habitats and biodiversity conservation: What activities are implemented to realize the conservation goals and targets?
Implementation activities
The natural meandering structure of the river was reestablished, its concrete river bed removed, river banks greened to create a natural barrier between the river and adjacent agricultural spaces, was reestablished. The reinstatement of natural elements such as dead wood shall reinforce the regeneration of the water body (Ref. 1).
To prevent further silting of the Aa lake, a sand filter was built into the upper stream which will save the costs of mud removal from the lake (Ref. 4).
In one part of the intervention area, renaturalization had been employed in 1996 already. However, this gave rise to the development of still waters in the Aa stream which affect the natural flow of the river and causes algae bloom during the summer months. The intervention created new river arms disconnected from these still waters to reestablish the natural water flow and improve the water quality in these stretches (Ref. 1)
To prevent further silting of the Aa lake, a sand filter was built into the upper stream which will save the costs of mud removal from the lake (Ref. 4).
In one part of the intervention area, renaturalization had been employed in 1996 already. However, this gave rise to the development of still waters in the Aa stream which affect the natural flow of the river and causes algae bloom during the summer months. The intervention created new river arms disconnected from these still waters to reestablish the natural water flow and improve the water quality in these stretches (Ref. 1)
3. NBS domains, ES and scale
4. Governance and financing
5. Innovation
Type of innovation
Please specify technological innovation
The natural meandering structure of the river was reestablished, its concrete river bed removed, river banks greened to create a natural barrier between the river and adjacent agricultural spaces, was reestablished. The reinstatement of natural elements such as dead wood shall reinforce the regeneration of the water body (Ref. 1).
Novelty level of the innovation
Please specify novelty level of the innovation
Renaturalization is a common procedure that has been applied for decades. Ever since 1995 there have been renaturalization works in the area and there are others just being conducted (Ref. 5).
Replicability/Transferability
Please specify Replicability/Transferability
Unknown
