Anti-seepage structure of water supply and drainage engineering building

The utility model relates to the technical field of drainage engineering, and discloses a water supply and drainage engineering building anti-seepage structure which comprises a water guide hopper and a blow-off pipe, the bottom end of the water guide hopper communicates with a downpipe matched with the blow-off pipe, the bottom end of the downpipe extends into the blow-off pipe, and a butt joint assembly is installed between the downpipe and the blow-off pipe; a matched annular plate is fixedly installed in the blow-off pipe, a water guide opening of a rectangular structure is formed in the annular plate in a penetrating mode, two symmetrical baffles are rotatably installed in the water guide opening, the baffles are obliquely arranged, and a water seepage prevention mechanism is installed between the baffles and the annular plate. The blow-off pipe of the drainage project has a good sewage backflow prevention function, and therefore the sewage leakage phenomenon is effectively avoided. 本申请涉及排水工程技术领域，且公开了一种给