Water supply and drainage device

The utility model belongs to the technical field of power transmission and transformation project supporting facilities, and particularly provides a water supply and drainage device. Comprising a three-way pipe, a flow guide pipe, a self-priming pump, a lower taper concave annular disc and an upper taper convex annular disc, a flange top cover is arranged on the upper end face of the three-way pipe, and a water outlet is formed in an upper pipe body; the lower taper concave annular disc comprises a first bottom disc and a first taper sleeve; a water inlet port is formed in the tip of the lower end of the first conical sleeve; the first chassis is mounted at the lower end of the three-way pipe; the self-priming pump is arranged in the three-way pipe, and the bottom end of the self-priming pump penetrates through the first through hole and is arranged in the conical sleeve of the lower taper concave annular disc; the upper taper convex annular disc comprises a second bottom disc and a second taper sleeve, a sec