The Traunfall is a waterfall of the Traun in Upper Austria.
It is located between the two towns of Steyrermühl and Roitham, on the municipal boundary between Desselbrunn and Roitham.
The waterfall has a drop of around twelve meters and is around 200 meters long.
This extraordinary length is due to the fact that it is not perpendicular to the river bed, but runs diagonally from the left bank of the river to the right.
In the course of the construction of the "Traunfall" power plant around 1900, the fall channel for the raftsmen, also known as the "good fall", was eliminated and the "wild fall" was greatly changed by a concrete weir system.
Due to the gradient, the Traunfall was a natural obstacle to shipping for a long time.
In 1311 it was made navigable for the first time.
What this construction looked like is no longer known today.
It was only in the 16th century that the "mobile case" or "good case", as it was also called, was finally expanded.
It was built by master wood, Klaus and hydraulic engineer Thomas Seeauer from Bad Goisern.
The fall channel had a length of 396.5 m and an average width of 6.1 m. The slope of the channel was not uniform, it was 15% at the beginning and 65.7% at the end. In order to reduce the water speed of the very steep gradient - especially at the end of the canal - slits were left free in the bottom of the channel. The water level was 90 cm at the beginning and only 30 cm at the exit. The passage through this raft alley takes about 54 seconds and was very risky with the means at that time.
A model of the entire system can be viewed in the Schiffleutmuseum in Stadl-Paura.
Nothing remains of the fall channel today.
Like many wooden buildings on and along the Traun, it became a victim of modernization.
Today, an underground watercourse runs along the old canal, which is used to operate the "Traunfall" hydroelectric power plant. The artificial rock face and some metal struts are still preserved today.