The problem of the clogging of open drains by drifting snow has become more significant along with the appearance of tendencies and considerations regarding the rehabilitation of these artificial watercourses by woody vegetation growing on slopes and riparian buffers. Referring to the full-scale field measurements supplemented with the results of hydraulic modelling of drifting snow, conducted to examine the influence of trees and shrubs growing on open drain slopes on the clogging of drains by snowdrift, it was determined that: (1) woody vegetation, influencing the distribution of snow within the riparian zones of the forested drain, contributes to the reduction of snow accumulation in its bed; (2) the clogging extent of forested drains depends on the type of pattern of cross section of woody vegetation strips (on this point there are some considerations presented); (3) it is possible to use hydraulic modelling of drifting snow to forecast some practical issues related with this phenomenon.