Which type of rainfall is considered ineffective in hydrology?

In hydrology, ineffective rainfall refers to precipitation that does not contribute to the replenishment of groundwater or the effective utilization of water resources. Rain that runs off quickly and does not absorb into the soil is classified as ineffective because it fails to infiltrate the ground and does not enhance soil moisture, thereby having limited value for irrigation or groundwater recharge.

When rainfall quickly flows over the surface, it often leads to issues such as runoff and erosion, rather than benefiting plant life or contributing to soil health. This makes it ineffective for purposes such as agricultural water management and ecological sustainability. Such rainfall might lead to flooding, but its primary characteristic is the lack of absorption, which diminishes its value in hydrological processes.

In contrast, rainfall that saturates the soil, filters through the ground, or contributes to flooding could all be seen as effective in various contexts, depending on the specific hydrologic needs or concerns being addressed.