6.964 kilometers. First of all, because Zoucheng is the hometown of Mencius, in order to commemorate the father of Confucianism, Zoucheng people renamed Xiwei Reservoir Mengzi Lake. In order to solve the problem that the water level of Mengzi Lake is low all the year round and the water area is shrinking day by day, Zoucheng municipal government plans to implement the water diversion and replenishment project of Mengzi Lake, and transfer the water from the four southern lakes to the city, so as to make every effort to build an ecological water system of Mengzi Lake with well-connected water system, water city compatibility and water and green contrast. By then, Mengzi Lake will be a vast and colorful place for Zoucheng citizens to punch cards in online celebrities.