Mobile Discharge Measurement

Sommer GmbH (Austria) adds a new technology to discharge measurement devices. Discharge measurement of rivers, irrigation channels or technical canals is daily business for hydrologists worldwide. The Sommer TQ tracer system offers new capabilities where conventional equipment, such as mechanical flow meter or ADCP boats, fails.

Conventional measurement equipment has certain limitations. On the one hand a minimum water depth is required and on the other hand the water may not be too turbulent, in order to avoid the risk of losing the flow meter or ADCP boat. This makes it impossible to get an accurate discharge in streams or in turbulent torrents.

With the recently developed tracer systems from Sommer GmbH, the TQ-F fluorescein and the TQ-S salt tracers, two new mobile devices are available which allow the immediate determination of the discharge of all flowing waters. The measurement principle is easy. With a minimum of two probes the fluorescence or the electrical conductivity of the water is measured. In the next step an exact amount of tracer medium, e.g. normal salt NaCl, is poured into the river. By measuring the change of conductivity or fluorescence the dilution and consequently the discharge of the river is determined.

Whereas the salt tracer TQ-S is limited to a maximum discharge of approximately 10 m³/s, due to the need of 5 kg/m³ salt, the fluorescein tracer TQ-F has almost no limitation. The tracer medium for the TQ-F is either Uranin or Rhodamin of which approx. 1 g/m³ is required.

Great advantages of the Sommer tracer system are its mobility and usability. Within 10 minutes accurate discharge results can be obtained directly on a laptop or mobile phone via Bluetooth, using the included software TQ-Commander. The use of up to four probes verifies the results.