| 摘要 |
PROBLEM TO BE SOLVED: To provide a drainage system for a building capable of ensuring use of a drainage instrument of a toilet or the like for a fixed period even when a public sewerage system is made unavailable in the case of a disaster such as an earthquake.SOLUTION: A drainage system 10 for a building is applied to a condominium 100 or the like and includes drain pipes 12 for conveying drain water to a public sewerage system 102 and an emergency drain water reservoir tank 14. In the drain pipe 12, a branch part 16 is provided which includes a first water outlet 26 and a second water outlet 30. The first water outlet 26 is connected to the public sewerage system 102, and the second water outlet 30 is connected to the emergency drain water reservoir tank 14. In the branch part 16, conduit line switching means is provided for selectively switching a flowing direction of drain water. In the case of emergency where the public sewerage system 102 is unavailable, the flowing direction of drain water is switched to a side of the second water outlet 30 by the conduit line switching means, and drain water is stored in the emergency drain water reservoir tank 14 in place of being discharged to the public sewerage system 102. |
