Before the discharge measurement, some calibration tests were made before lowering the acoustic doppler current profiler (ADCP) to the river channel. © Jari Silander.
SEVIRA-project arranged a field measurement campaign with the discharge measurement specialists both from the Southeast Finland ELY-centre and Finnish Environment Institute SYKE in October 27th, 2020. Discharge and water level were measured in the River Rakkolanjoki and the River Hounijoki in Finland. At the same time there was filmed some material for the future SEVIRA webinars. The discharge i.e. the amount of the flowing water in time, is one of the key features in the hydrological monitoring linked also to the nutrient loading.
Finnish discharge experts used an acoustic doppler current profiler (ADCP) device from SYKE to track the discharge and collect very accurate discharge and river channel data. The ADCP was mounted in a certain type of small boat, a catamaran, and pulled across the river channel from side to side. In the River Rakkolanjoki also a different type of discharge meter was used; MF Pro electromagnetic flow meter from the Southeast Finland ELY-centre was applied at the same time for comparison. The discharge experts can now compare the discharge data obtained with the two devices based on different measurement technique.
Despite the very cloudy and rainy weather, or perhaps due to that, the measurements succeeded and good validation results for the new rating curves of the rivers as well as the comparison of measurement techniques were collected. The Finnish experts aim to do new on site -measurements with the ADCP on high water level situations this autumn or next spring, and therefore monitor closely the course of the winter.
In the River Rakkolanjoki, the discharge was measured with two devices: acoustic doppler current profiler (ADCP) and electromagnetic discharge meter (MF Pro discharge meter). © Jari Silander.