Reduction of fine sediment aggradations in waters of the Weinviertel - LandSed

The heavy precipitation of recent years in the Weinviertel region has led to increased soil erosion and sedimentation in affected water bodies. Effects on flood protection as well as on the ecology of water bodies often have to be remedied at high costs. Therefore, measures for the reduction of sediment input are needed with the aim of securing the flood discharge capacity.

Overview:

Project processing:
F. Darmann, E. Schmaltz, G. Schmid, M. Karner, P. Strauss

Client:
Province of Lower Austria

The photo was taken at the Obermallebarn monitoring station on the Göllersbach stream during a precipitation event in June 2020. You can see a flood in the bank area, which is densely overgrown. On the opposite side of the stream, narrow steps lead up to the road.
© Wolfgang Summer

Brief Description:

The LandSed project is carried out in cooperation with the Institute of Hydraulic Engineering and Hydrometry and the civil engineering office Dr. Summer and deals with the reduction of fine sediment aggradations in water bodies of the Lower Austrian Weinviertel. Of particular interest are the origin of suspended sediments, the sediment input potential as well as the possibilities to reduce sediment input.

To better understand these processes, a research basin for flood and sediment retention was built in Breitenwaida (in the district of Hollabrunn), which was completed in September 2020. This will provide insights into the soil erosion of an agriculturally used area as well as a detailed observation of the sedimentation behavior of the solids introduced into the basin. In the inflow and outflow of the research basin, measuring weirs for flow measurement as well as measuring equipment in the form of automated sample collectors for measuring sediment concentration have been set up.

In order to better record the situation in the water body itself, two additional measuring sites for the continuous recording of the suspended sediment load were put into operation. These are located on the Zaya in the local area of Asparn and on the Göllersbach in Obermallebarn, directly at the gauge measuring site. Similar to the research basin, sample collectors and additional turbidity probes are installed for continuous measurement of turbidity. In order to obtain information on nutrients, the sediment taken from the research basin and the two measuring points is also analyzed chemically and physically.

Additional information