Between April 2024 and July 2025 the German team measured water temperature of the water column at the dam wall, and of the inflows at the surface water of the predams. In parallel, we also measured the current velocities using two ADCPs (acoustic current doppler profilers) at two points in the reservoir. The temperature measurements showed high frequency and small scale patterns in the reservoir stratification, and showed that the temperature of the inflows is up to 10 degrees (Celsius) colder than the surface water of the reservoir in summer. This means that inflows likely plunge and flow along the thermocline.
Heatmap of water temperature at the deepest point of the main reservoir, near the dam wall.
Comparison of the surface temperature at the main reservoir (OT1) and the two inflows at the predams (Kernwasser OK1, and SIlbergraben OS1).