Rainwater bioretention facility for mountainous cities

The utility model discloses a rainwater bioretention facility for a mountainous city. The system comprises a detention pond, a reservoir at the top of the detention pond and vegetation on the top surface of the detention pond, one end of the detention pond is connected with a road water collecting side; a sponge body is arranged on the detention pond on the water collecting side of the road; a covering layer is arranged at the bottom of the water storage layer; a vegetation soil layer is arranged at the bottom of the covering layer; a sand layer is arranged at the bottom of the vegetation soillayer, an impermeable membrane isolation layer is arranged at the bottom of the sand layer, a gravel layer is arranged at the bottom of the self-defense isolation layer, a perforated pipe is arrangedin the gravel layer, a through hole is formed in the perforated pipe, and a second overflow pipe communicated with the perforated pipe is arranged in the gravel layer. Compared with the prior art, the rainwater bioretention f