Water treatment device for low impact development

摘要

The present invention relates to a water treatment device for low impact development (1) with which low impact development can be applied appropriately by increasing soil penetration while preventing various pollutants contained in early rainwater from penetrating into the ground, including a reservoir main body (2) having a plurality of water holes (21) which are buried in the ground and have openings through which upper and lower rainwater are introduced and which communicate with the inside and outside and the rainwater flowing into the space is drained to the outside; a gravel layer (3) having a thickness and containing gravel embedded in the ground while surrounding the outer peripheral surface of the storage main body (2); a sand layer (4) having a thickness and containing sand buried in the ground while surrounding the outer circumferential surface of the gravel layer (3); a nonwoven fabric layer (5) including a nonwoven fabric which is applied while covering the outer circumferential surface of the sand layer (4); a backflow prevention lid (6) disposed in the opening of the storage main body (2) to introduce rainwater into the space and prevent rainwater contained in the space from flowing backward; and a floating net (7) provided in the space portion of the storage main body (2), accommodated such that pumices (71) which are smaller in specific gravity than water and floated are filled with a space of 1/3 of the space portion of the storage main body (2), and formed so as to be aligned with the transverse sectional shape with respect to the space portion of the storage main body (2). The floating net (7) floats by the rainwater flowing from the inside of the storage main body (2) and does not close the water storage holes (21) of the storage main body (2).