Groundwater dynamic, it is to point to the groundwater level, water quantity, water temperature, chemical composition elements such as the process of change over time. Groundwater dynamic very day and night, seasons and years of cyclical changes. Groundwater dynamic by natural factors (climate, hydrology, tidal, geological, heavenly body, planet gravity, etc.) and human factors (water seepage drainage, irrigation, reservoir and channel, artificial recharge, etc.). Different types of groundwater, due to the different influence factors, the dynamic is different also. Such as seasonal dynamic changes of diving often than confined water significantly, the precipitation and the surface water supplies diving dynamic is not the same.

Groundwater dynamic observation, it is of a regional groundwater dynamic elements (such as water level, water temperature, water flow, artesian well water inflow, etc.), select a representative of springs and Wells, holes, etc. According to certain time interval and technical requirements for observation, records and documentation work. According to its property can be divided into regular observation and special observation. The latter refers to a certain period of time or for a particular purpose and dedicated group of observations, such as flood season special perception of the relationship between river and groundwater, etc.

Hydrological system since the mid 50 s in water conservancy department, on the basis of the hydrologic network in the natural water chemical testing, the increasing water pollution monitoring project in the early 70 s, 80 s until now has developed into to each type of water, aquatic organisms and bottom water environmental elements such as monitoring, water quality, water quantity and has the advantage of synchronous monitoring. At present has been built by the department, river basin, provincial and city level 4 for a total of more than 250 water environment monitoring center of the national water environment monitoring system, monitoring institutions at all levels have been through the national metrology authentication. The national water quality monitoring network is composed of more than 2600 water quality monitoring stations, regular monitoring and evaluation of surface water, groundwater, water quality, directly for water resources management and protection, etc.

According to the law of the People's Republic of China on the prevention and control of water pollution to the water conservancy department responsibilities of each river basin water resources protection agency in 1997, in the seven major river main stream boundary water set up 329 monitoring sites, forwards to provincial boundary water water environment quality condition on a regular basis. At present, the water conservancy department has mastered the basic system of seven river water system, zhejiang fujian and Taiwan rivers and inland lakes and south river surface water, groundwater and western yunnan provincial boundary water quality basic situation.

Since 1989, the ministry of water resources under the condition of using quality control, quantity traceability of the water environment monitoring center at all levels to provide the system of water quality monitoring results, released on a regular basis the major rivers in China focus on river water quality bulletin, the provincial boundary water quality of water environment bulletin and the ten-day reports focus on urban water supply water source water quality condition, participate in the preparation of water resources of the People's Republic of China (section) water quality and water quality of annual report of the People's Republic of China, at the same time, a year for the China environment bulletin provides the main drainage water quality monitoring and evaluation results.