# Critical Hydraulic Gradient

Critical hydraulic gradient, abbreviated as \(i_c\), is the change in height (pressure) to length between any two points.

## Critical hydraulic gradient formula

\(\large{ i_c = \frac{ \gamma_{sub} }{ \gamma_w } }\) | |

\(\large{ i_c = \frac{ G_s \;-\; 1 }{ 1 \;-\; e } }\) |

### Where:

\(\large{ i_c }\) = critical hydraulic gradient

\(\large{ \gamma_{sub} } \) (Greek symbol gamma) = submerged unit weight

\(\large{ \gamma_w } \) (Greek symbol gamma) = unit weight of water

\(\large{ G_s }\) = specific gravity of soil

\(\large{ e }\) = void ratio

Tags: Equations for Water Equations for Hydraulic Equations for Soil Equations for Geotechnical