Author(s): Marin Paladin; Josip Paladin; Dijana Oskorus
Linked Author(s):
Keywords: Boundary Water Level Method; Continuous discharge monitoring; Hydraulic modeling; Open channels; Ultrasonic sensors
Abstract: This research introduces an innovative and low-cost approach for continuous discharge monitoring in open channels. The method determines flow using a standard 1D hydraulic model that relies on 6-8 geodetic cross-sections and stage-hydrograph boundary conditions from direct, non-contact water level measurements at the boundaries of a defined reach - hence the name "Boundary Water Level Method", or BWLM. By employing affordable ultrasonic sensors, this technique shows strong potential for application in smaller basins that are often excluded from state hydrological networks due to financial limitations. Developing new and innovative monitoring methods is essential, as they represent the only practical alternative to increasing budgets for flow measurements. As with any newly developed approach, the reliability of this method must be verified, particularly since it is intended for unstudied channels and for use in supplementary measurements. The proposed method is validated at two pilot sites so far, by comparing the model discharge and control measurements conducted by velocity-area method. The method gives reliable discharge values using standard hydraulic roughness values from the literature, with deviations from control measurements below 10%. Price of installment is estimated at around 2-5% of the price of comparable methods in use.
Year: 2026