Obernau barrage
| Obernau barrage | ||
|---|---|---|
 Aerial photo from August 29, 2008 |
||
| location | ||
|
||
| Coordinates | 49 ° 56 '2 " N , 9 ° 7' 43" E | |
| Country: | Germany / Bavaria | |
| Place: | Obernau (Aschaffenburg) | |
| Waters: | Main | |
| Water kilometers : | km 92.91 | |
| Data | ||
| Responsible WSA : | WSA Aschaffenburg | |
| Construction time: | 1926 to 1929 | |
| lock | ||
| Type: | Chamber lock | |
| Category: | Va | |
| Usable length: | 299.18 m | |
| Usable width: | 12.00 m | |
| Height upstream : | 112.52 m above sea level NN | |
| Average height of fall : |
4.01 m | |
| Others | ||
| Associated weir: | Main weir Obernau | |
| Associated power plant: | Hydroelectric power station Obernau | |
| Was standing: | Nov 2017 | |
The barrage Obernau is a barrage of River Main in Main kilometer 92.91 in Obernau , Aschaffenburg .
history
The barrage was built between 1926 and 1929 without a raft lane . The entire system consists of a three-field drum weir (storage target 402 cm above the underwater) with a fish pass and boat lock , a 300 m long lock chamber with an upper and lower outer harbor and the hydropower plant , the two Kaplan turbines of which together provide an average annual output of around 26 million kWh.
Building
The iron weir footbridge can be reached via steep stairs, otherwise freely accessible. In contrast to most of the barrages on the Main , the gears and chains for raising and lowering the weir drums are largely visible. The progress of construction at that time was clearly visible in the untreated concreting sections with their nests and sintering . Since concrete damage was not only evident on the heavyweight walls of the lock chambers, the barrage was renovated from 2008 onwards.
Ship in lock basin
Weir system (bottom)
Weir closed
Weir open
Power plant (outlet)
New building
Since the Obernau barrage is no longer considered to be sufficiently operationally safe, mainly due to frost damage in its already quite porous core concrete, a new, water-filled inflatable weir system for three fields as well as new chambers for the ship and boat lock are planned approx. 160 meters downstream. The plan approval procedure started in July 2017.
Because the new 300 m long and 12.50 m wide chamber of the ship's lock is to be used for the flood discharge, the upper lock gate is not intended as a mortise gate like the lower one, but as a rotating segment gate. The new weir system is to be bridged from bank to bank by a barrier-free weir that is permanently accessible to the general public.
The construction project is to be carried out as far as possible from the left bank of the Main and over a temporary bridge. After planning approval and two years of preparation, construction is scheduled to begin in 2022. The construction time to commissioning is estimated at seven and a half years. After that, the old lock chamber is to be kept operational for another five years and then gradually backfilled over a period of another two years.
Apart from the necessary adjustments to the lower power plant channel, no changes are planned for the hydropower plant built by Rhein-Main-Donau AG between 1926 and 1930. The power plant has two Kaplan turbines with an output of 3,200 kW, the absorption capacity of which is 175 m³ / s.
Web links
- Project site barrage Obernau - project site new construction of the barrage Obernau. Federal Waterways and Shipping Administration, accessed on January 2, 2020 .
- Animated film construction of the Obernau barrage. Federal Water and Shipping Administration, accessed on October 28, 2017 .