Rivers and lakes are formed by water. What is maintaining the health of rivers and lakes?

Rivers should be flowing, not static; You should have your own development space, not too hard; The water quality should reach or be better than Class III to meet the needs of human life; The biodiversity is rich, there are many fish and shrimp analogies, and the phytoplankton density is relatively low, or close to the historical state; It has a sustainable social service function. The health status of rivers and lakes should be the organic integration of water quality, water quantity and water ecology.