Model Trial of a Rainwater Collect System in a Southern City of China

Rainwater utilization by means of pipe-bound systems in private households, public buildings and industry, which is spring up at Germany in ninety years last century. The idea was to save valuable drinking water and not to use it for flushing toilets etc but to substitute it by collected rainwater. This paper describes a model rainwater collect system that has been constructed within a residential area. The system has been fitted with a monitoring system, which has been used to record the water delivered and to estimate the rainwater collected over approximately a 3-month period. The results are used to calculate the collection efficiency of the system compared to potential gains determined from local rainfall data. This data has also been used to calculate the revenue cost savings for this system. Finally, this paper considers the effects of alternative roof area and tank sizes on system economics. This shows that present tank is oversized and that savings could be made by specifying a smaller tank size or enlarging the roof area, and then reduced the total cost and made the system more economic.