The invention relates to the technical field of building drainage, in particular to a drainage
system for a building house. The drainage
system comprises a collecting box, a filtering device, a waterstorage tank and a flow guiding
pipe; the top of the collecting box is in an opening shape; the filtering device is used for filtering rainwater and arranged in the collecting box; a communicating
pipe communicating with the collecting box is mounted in the collecting box, and the height of the end, close to the collecting box, of the communicating
pipe is not smaller than the height of the end, close to the
water storage tank, of the communicating pipe; the flow guiding pipe is mounted in the
water storage tank and communicates with the
water storage tank; a
solenoid valve is mounted in the flow guiding pipe, and the end, away from the
water storage tank, of the flow guiding pipe is bifurcated into a first flow dividing pipe and a second flow dividing pipe; an opening and closing assemblyused for opening and closing a pipe opening of the first flow dividing pipe and a pipe opening of the second flow dividing pipe is arranged in the flow guiding pipe; and the end, away from the flow guiding pipe, of the first flow dividing pipe communicates with an indoor
water supply system, and the end, away from the flow guiding pipe, of the second flow dividing pipe faces
green vegetation. Thedrainage system has the effects of making full use of the rainwater and reducing waste of
water resources.