Context: Tainter gates (radial gates) are commonly used in dam spillways to control water flow.

Application: A Tainter gate is a segment of a cylinder. The hydrostatic force acts normally to the curved surface at all points. Because all these normal forces pass through the center of curvature of the gate, the resultant hydrostatic force produces zero moment about the pivot point (trunnion). This ingenious design means the only force required to open or close the gate is that needed to overcome the gate's weight and trunnion friction, making it highly efficient for controlling large volumes of water.

Context: Vertical or inclined sluice gates are critical for regulating flow in irrigation channels and sewers.

Application: The design of a sluice gate must account for the immense horizontal hydrostatic force pushing against it, which translates to high frictional forces in its guide slots. To lift the gate, the lifting mechanism must overcome both the dead weight of the gate and this frictional resistance. Engineers often incorporate rollers or use low-friction materials to manage these forces, ensuring the gate can be operated reliably during varying flow conditions.