1. Necessity of the construction project
During the flood in June 2013, the existing left Ohredeich between the dike km 8.00 and the dike km 11.00 was overflowed. The adjoining area was flooded and it had to be secured in several places by sandbag shoring or by a surge of sand, which was coated with water-repellent film. For example, the Handwerkerring industrial estate in Wolmirstedt and the district road (K1171) Wolmirstedt in the direction of Glindenberg were secured. These measures made it possible to protect the south-eastern outskirts of Wolmirstedt from imminent flooding. The flooded areas are an officially designated flood plain. Excluded from this are only the built-up areas. The existing left ear medley between the Ohrebrücke (K1171) and the high bank between Farsleben and Zielitz is affected by mountain subsidence and is thus continuously damaged or the existing level of protection is reduced. For this reason, the location Wolmirstedt and the K 1171 are to be secured against flooding.
2. Nature, scope and purpose of the project
Based on the findings of the June flood in 2013, a flood protection system (HWSA) must be planned taking into account the Water Resources Act, the Water Act saxony-Anhalt, DIN 19712 and the DWA leaflet 507-1.
With regard to the constant lowering of the level of protection on the left Ohredeich (dike km 3.00 to 11.0), a dike gap closure between the existing high bank and a connection point in front of the well-known subsidence area on the left Ohredeich must be established. The protection objective is the settlement areas of the city of Wolmirstedt east of the railway line as well as the road connection from Wolmirstedt to Glindenberg (K 1171).
In order to avoid such a situation in the future, the project "HWSB Rückstaudeich Wolmirstedt" is to be implemented as a dike gap closure. In this context, polder production is not part of this planning. Rather, it is about avoiding uncontrolled overflow of the flood plain and protecting the adjacent buildings from flooding. A permanent stable, low-maintenance, maintenance-friendly flood protection system (HWSA) is to be planned as a backwater dike with corresponding inspection and dike defence paths on the land side in accordance with the requirements of the LHW. This planning includes all necessary structural facilities for flood protection, all traffic facilities, special structures (sieves, dike ramps) and necessary adaptations to the TöB facilities.
The left Ohredeich between the planned route of the HWSB Backstaudeich Wolmirstedt and the K 1171 is also to be renovated or expanded in the course of this construction project. The removal of the left ear dike takes place in cross-section and at altitude such as the HSWB backwater dike Wolmirstedt. The extension or widening of the dike takes place on the land side, on the water side only the slope of the embankment is corrected and adjusted.
2000 m new dike construction, incl. water-side seal, h=1,80m, Bn 1:3,
3 dike crossings, 2 sieves, manufacture
Supply and install 30,050 m³ of support body material 0/8
Supply and install 6,000 m³ clay seal (water side)
Arrange 2 pcs - made of reinforced concrete/concrete in the new dike,
incl. shut-off valves (per spindle slider, check valve) DN 1000
55m Wastewater Pressure Pipeline Media Pipe DN 250 Protective Pipe DN 350 Supply and lay
600m dike rehabilitation (existing Ohredeich)
4950 m³ Support body material 0/8 deliver and install
2600m Deichkronenweg (Asphalt)
2600m Deichverteidigungsweg (Asphalt)
52 st felling and clearing trees
various compensatory measures, earthworks, plantings,
Topsoil and lawn seeds