Saturated vs Unsaturated Flow

Saturated flow occurs when all the pores in soil or a medium are filled with water, allowing water to move freely through it, like a sponge soaked with water. Unsaturated flow happens when only some pores are filled, creating air gaps; here, water moves more slowly and is influenced by gravity and capillary forces. Think of saturated flow as water rushing through a fully soaked sponge, while unsaturated flow is like water slowly seeping through a dry sponge. These processes are important in understanding groundwater movement, soil moisture, and irrigation.