Austria's deepest lock to be refurbished
VERBUND, Austria's largest electricity company, is overhauling the lock at its hydropower plant in Upper Austria. For five months now, the gigantic Danube lock has been undergoing refurbishment work in order to function smoothly again by the end of March 2019. At over 23 metres, it is the deepest lock on the Danube in Austria. Capital expenditures amount to around 2 million. In the course of the inspection works, VERBUND installed a research instrument for fish migration in the Danube in the lock. The aim is to find out which fish migrate, when, how and where.
"The giant bathtub is being completely overhauled, front to back", said VERBUND project manager Kurt Schauer. “It is the deepest lock on the Danube in Austria and thus in Upper Austria and needs some TLC every now and then, comparable to a car service”. Schauer is overhauling the entire hydraulic steel structure in order to increase its service life. The filling and emptying closures are maintained and the mitre gates are inspected, i.e. the seals are checked and replaced if necessary, and cracks and damage to the construction repaired.
The giant bathtub of Aschach is the deepest in all of Austria.
When empty, the lock resembles a giant bathtub: at 230 metres long and 24 metres wide, it offers room for several ships for locking. However, the Aschach lock has a special feature: it is 23.4 metres deep and thus the deepest anywhere to be found on the Austrian Danube. The reason it is so deep is because the extremely high drop of 15 metres has to be compensated for. On the route from Engelhartszell to Aschach, the gradient of the Danube is very pronounced, resembling that of a mountain river. To ensure that the locking is within the specified time frame of approx. 20 minutes, the locks at the VERBUND Aschach power plant have specially designed filling and emptying channels.
The inspection works are scheduled for every six to eight years. This year, the left lock chamber of the Danube power plant Aschach had its turn. The work will be completed by the end of March 2019, when it will once more function properly and will be able to handle almost 24 lockings per day.
Research project on fish migration
In the course of the lock overhaul at the Danube power plant Aschach, a pilot test is also set to commence. VERBUND is testing a new technology that can be used to study the large-scale migration of fish in the Danube. For this purpose, ten antennas were installed in the empty lock in February, which in the future will count the marked fish and record the fish migration, i.e. which fish migrate when and where.
The pilot experiment is part of the research project for a fish bypass at Ottensheim-Wilhering. So far, about 7,000 fish have been tagged. The study identified around 40 species of fish that are currently living in the Danube. With the new fish counting system, VERBUND will be able to find out whether and which fish migrate through the lock. At the end of March, the generally overhauled lock will be put back into operation and the fish count will commence.