Feet of water Unit | All you need to know

The feet of water (ftH2O) is a unit of pressure commonly used to measure fluid pressure and level differences, especially in industrial and engineering applications. It provides a practical way to understand hydrostatic pressure and fluid dynamics.

Definition and Usage

The feet of water are defined as the pressure exerted by a column of water one foot in height at the standard acceleration due to gravity. This unit is valuable for quantifying the pressure generated by the weight of a fluid column.

Applications in Engineering and Hydrodynamics

The feet of water are applied in various areas:

  • Fluid Level Measurement: It's used to measure liquid levels in tanks and reservoirs.
  • Hydrostatic Pressure: Engineers apply it to calculate pressure in submerged systems.
  • Fluid Dynamics: It's used to assess pressure variations in fluid flows.

Conversions and Equivalents

Understanding conversions of feet of water to other pressure units is important:

  • 1 Foot of Water (ftH2O) = 2.9890669 kPa (kilonewton per square meter)
  • 1 Foot of Water (ftH2O) ≈ 0.4335275 psi
  • 1 Foot of Water (ftH2O) ≈ 0.8826099 inches of mercury (inHg)
  • 1 Foot of Water (ftH2O) ≈ 27.679904 millibar (mbar)

Usage in Fluid Engineering and Hydrology

The feet of water have significant applications:

  • Fluid Systems: It's used to assess pressure and level changes in pipelines.
  • Hydrodynamic Analysis: Engineers apply it to study fluid behaviors in various contexts.
  • Water Management: It helps in understanding pressure variations in water distribution systems.


The feet of water (ftH2O) is a crucial unit of pressure in fluid engineering and hydrodynamics. Its ability to quantify hydrostatic pressure and fluid level differences makes it an essential tool for understanding fluid systems, designing pipelines, and assessing water-related applications.

Keywords: Feet of Water, ftH2O, pressure unit, fluid dynamics, hydrostatic pressure, conversions