Water drain, especially for a building roof, has an inflow opening with an outflow pipe for surface water and a second inflow with a smaller outflow pipe to take a pressure flow of higher accumulated water

摘要

The water drain, to carry off water from an impermeable surface (29), has an inflow to take free surface water into an outflow pipe (8). A second inflow opening (17) takes water accumulated at a given height over the first inflow opening (6) in a pressure flow into a second outflow pipe (18) with a smaller cross section. The second outflow pipe is inserted at least partially into the first outflow pipe.