What is the effect on reservoir water level when inflow exceeds outflow?

When inflow exceeds outflow in a reservoir, the additional water entering the reservoir increases the overall volume of water present. This results in a rise in the water level of the reservoir. The principle behind this is simple: if more water is coming in than is being discharged or flowing out, the net gain in water volume will cause the surface level to go up.

The inflow can come from various sources, such as rainfall, inflow from a river, or snowmelt, while outflow typically includes water being released for use or to maintain certain water levels downstream. In a balanced system, inflow and outflow would equalize, leading to a stable water level. However, when inflow surpasses outflow, the balance is shifted in favor of accumulating water, leading to continued rises until a new equilibrium is reached or management measures are taken to adjust the outflow.

Options suggesting that the water level falls, remains unchanged, or becomes stagnant do not accurately reflect the physical dynamics of water flow within a closed system like a reservoir when faced with excessive inflow. The direct relationship between inflow and outflow is critical to managing reservoir levels effectively.