Fushougou Project was built between 1068 and 1077 by Liu Yi， and the project still plays the role of drainage.The planning and design of the project reflects the simple“ system science” idea.City walls， drainage networks， ponds for temporary storage flood and“ water windows” are treated as a whole system that bear their responsibilities，working together based on the principle of adapting to local conditions.The project effectively carries out flood control and drainage.