The goal in this thesis was to determine the geometric and basic hydraulic characteristics of the bridge flow profile on Vlarka watercourse. Vlarka watercourse is located in protected landscape area of Biele Karpaty. We determined the characteristics of the river basin, calculated the maximum runoff from the river basin using the Duba’s formula and N-year discharges. We also found the capacity of the bridge flow profile at the station 0,932km. The profile could be able to carry a 100-year flow, if the 0,5m reserve wouldn’t be considered. Using the calcutations, we found out that the actual flow would be QS =14,8 m3⋅s-1 considering the 0,5m reserve. The bridge does not have the capacity to perform even a 5-year flow (Q5 = 16.3 m3 ∙ s-1). In order for the bridge to be able to carry a 100-year flow (Q100 = 41.7 m3 ∙ s-1), sufficient measures and adjustments to the riverbed must be made.