What term refers to the volume of water flowing in a river at a specific time?

The term that refers to the volume of water flowing in a river at a specific time is known as river discharge. Discharge is measured in cubic meters per second (m³/s) and represents how much water passes a particular point in the river over a designated period. Understanding river discharge is crucial for various applications, including flood management, water resource management, and ecological studies, as it provides insight into the river's health and capacity to support life.

The concept of river velocity pertains to the speed at which water flows, while river flow rate can be seen as a non-standard term that isn't commonly used in scientific contexts. River current usually describes the movement or flow of water and might not necessarily refer to the volume aspect specifically. Hence, river discharge is the most accurate and widely accepted term for describing the volume of water flowing in a river at any given moment.