| 摘要 |
PROBLEM TO BE SOLVED: To provide rainwater storage facility having a water conducting groove capable of uniformly guiding rainwater including sand toward a manhole side over the whole of a water storage tank regardless of the dimension of the area of the water storage tank.SOLUTION: In the bottom of the rainwater storage tank 1 formed by excavating the ground, a rainwater guide part 2 formed of a single water conducting groove 6 bypassed while bending spirally or bending backward, forward, rightward and leftward along the bottom face of the water storage tank 1 is constructed by combining a plurality of rectangular bent guiding rainwater guide unit members 10, each of which has a bent water conducting groove part 6a with an L-shape in planar view and a rainwater guiding slant face gently tilting downward toward the bent water conducting groove part 6A, with a plurality of rectangular linear guiding rainwater guide unit members 20 each having a linear water conducting groove part 6B and a rainwater guiding slant face gently tilting downward toward the linear water conducting groove part 6B. A rainwater storage part is formed when a water storage unit member is stacked on the rainwater guide part 2. |
