Abstract
We evaluated an advantage of the utilization of rainwater and treated domestic wastewater in urban area. The rainwater utilization is the use of rainfall on the roofs and collected runoff storm water in the storm water reservoir for flood control. In the reuse of treated domestic wastewater, wastewater from the kitchen is not reused. That is “Domestic Water Recycling System”. We evaluated the amount of conserved drinking water and the amount of decreased final effluent polluted matters by the unused water resources utilization. And we estimated the amount of carbon dioxide emission by the construction and operation of the unused water utilization systems. In the subject basin, the use of rainfall on the roofs and the domestic water recycling systeip are effective in the decrease of the resources consumption. And the domestic water recycling system is the most effective in the decrease of the environmental load.
