Separation dam to restore stream continuity, Detmold, AgA gGmbH, September 2017
The production of an approx. 73m long separation dam for the diversion of the broker's stream around the Brokhauser village pond, was implemented on the district of the city of Detmold.
To create a stream bypass around the village pond to allow stream continuity and reduce silting while the pond is still used as a retention area (water buffering).
The separating dam was designed to be erosion-proof and in the case of a flood to allow for overflow in order to use the pond as an additional retention space. A considerably smaller dam footprint with a narrow crest was designed.
To adapt to the terrain profile, three sections of the dam are designed, which give a uniform crown height over the entire construction.
Advantages of the topotube method:
- Erosion-proof structure: The geotextile tubes encapsulate the filling material creating a erosion-proof structure, reducing risk of damage to dam construction e.g. in the curves of the brook.
- Narrow cubature: low perineal contact area, small crown width
- Overflow construction: The tubes form an erosion-proof core within the structure and allow for overflow/overtopping.
- Use of the local soil excavation: savings on transport and landfilling of the existing soil as well as elimination of the purchase of suitable soil.
- Lower total costs: The automated laying process of the tubes and the saving on the filling soil (see previous point) have a favorable effect on the total project costs.
Implementation of the three different dam profiles over a building length of approx. 73m.
The design and implementation of the innovative separating dam was scientifically supported by the University of Applied Sciences Ostwestfalen-Lippe to gather further insights for subsequent projects. The following photographs document the construction works: