What does the height of the Yangtze River in Nanjing mean?

Nanjing Yangtze River water level height refers to the height of the free water surface of Nanjing Yangtze River water level station from the fixed datum (the fixed datum of Yangtze River water level should be Wusongkou sea level height). There are several hydrological stations along the Yangtze River, which are used to measure the water level, flow and other data of each station.

The water level measurement of the Yangtze River follows the "Wusong Zero Point and Wusong height system", that is, based on the measured water level data at Wusong Estuary of the Yangtze River, the elevation slightly lower than the measured lowest water level is taken as the draft zero point of the Yangtze River, which is officially determined as Wusong Zero Point.

Extended data:

Due to the high terrain in the west and low terrain in the east, the water level measured from the upper reaches of the Yangtze River to the downstream ports has gradually decreased. So compared with the same period, the water level in Wuhan should be higher than that in Nanjing.

Water level is an important hydrological data, and departments such as waterway transportation, flood control and ports have to measure water level every day. Especially in flood season, the water level of the Yangtze River is an important value for flood control and fighting.