抄録
In this research, we investigated quality of rain water used for roof tree planting system, general bath water and water treated with combined septic tank, and evaluated them according to the standard for household water. As a result, rain water was ranked AA, and other tested water was ranked between D and E. On the other hand, we detected algae, legionella, etc. in the water used for roof greening, and found out that water quality was deteriorated.