Groundwater Velocity Calculator 1. Bring up the Groundwater Velocity Calculator. Groundwater Velocity Water moves very slow when it is underground. Sometimes the water is moving through the soil, which has different textures that can change how fast water moves. When water gets deeper, it reaches the groundwater, which usually is made of different rock types like limestone and sandstone.
Water moves slower through soils or rocks that are tightly packed together.
This is like the channel lining from the last page. Just like water on the land surface, water underground is moved by gravity. For runoff speed, we used the channel slope to show this. For underground this is shown by an elevation change. The other thing that will slows down the water underground is the distance the water is going.