The following filtration flows with unknown free boundaries are investigated: in case of a flow past the Zhukovsky groove in the case when the soil layer is underlain along its entire length with an impermeable base and evaporation from the free surface occurs; in case of a flow past the Zhukovsky groove in the case when the underlying layer is a completely well-permeable aquifer and infiltration occurs on the free surface; when groundwater moves in a rectangular bridge with a partially impenetrable vertical wall in the presence of evaporation from the free surface; when groundwater moves to an imperfect gallery in the presence of evaporation from the free surface.