摘要 |
PROBLEM TO BE SOLVED: To provide a rainwater storage piping structure capable of efficiently storing only clean rainwater excluding initial rainwater.SOLUTION: A rainwater storage piping structure comprises: a rainwater inflow section 1 where rainwater flows into rainwater drainage piping therethrough; a temporary storage section 2 which temporarily stores the rainwater flowing thereinto; an overflow section 3a where the rainwater exceeding a predetermined amount of the temporary storage section 2 overflows; a storage pipe conduit 4 which stores the rainwater overflowing the overflow section 3; and a dam section 5 which is installed inside the storage pipe conduit 4. The storage pipe conduit 4 is arranged in a virtual horizontal position or has a downward slope from a most upstream side to a downstream side with a position of a pipe bottom at the most upstream side lower than the overflow section 3a. The temporary storage section 2 has a drainage section 2f which gradually drains the rainwater. When a volume of the rainwater flowing into the temporary storage section 2 exceeds the same drained through the drainage section 2f, a level of the rainwater in the temporary storage section 2 exceeds the overflow section 3a and the rainwater overflows into the storage pipe conduit 4. |