• Rectangular channel 1.80 x 3.00 m (h x w), partially concrete, partially dry-stone walls
• Part filled
• Rainwater and surface water
• Short calming section
• Manual detection of flow rates (level reading and Q/h-table) destroyed after flood

Definition of tasks

• Continuous, automated flow measurement of turbine intake
• High measurement accuracy despite short and unfavourable calming section for optimum use of the turbine for energy production
• Maintenance-free system required since no personnel available

• Ultrasonic transit time measurement with NivuFlow 650 was chosen due to the relatively clean medium.
• A section of the channel bottom was planed with concrete improving the hydraulic conditions at the measurement point.
• To achieve high accuracy after compensating skew flow behind the bend a crosswise 2-path measurement with transit time sensors mounted in different heights were installed.