Setting Your Pond Leveler to Vary The Flow Height As Water Depth Changes

Variable Flow Rate Example

The level of a pond is regulated with a Drainbox 6-inch controller. The owner wants the drain to flow as fast as possible when the pond is full, reduce to half the flow as the pond level falls by 12 inches and further reduce to ten percent flow as the pond level falls by 24 inches.

  • 100% flow above the maximum desired water level.

  • 50% flow at 12 inches below the maximum water level

  • 10% flow flow at 24 inches below the maximum water level.

 

The height of each stoplog panel is 6 inches

The inside width of the six-inch inline controller is 7 inches.

The cross-sectional area of a six-inch pipe is 28.3 square inches.

10% of of the 28.3 pipe area is 2.83 square inches.    2.83 square inches divided by 7 inches wide is 0.4 inches.

  • Open a 0.4 inch gap between the 4th and 5th stoplogs (24 inches) from the top.

50% of remaining flow - 10% additional flow = 40%     40% of 28.3 is 11.23 square inches.   11.23 divided by 7 is 1.6 inches.

  • Open a 1.6-inch gap between the 2nd and 3rd (12 inches) stoplogs from the top

Flow diagram showing three pipe sections with different flow rates and gaps: 2 inches full flow at the top, 1.6 inches at 40% flow in the middle, and 0.4 inches at 10% flow at the bottom, connected to a blue pipe system.
Line graph titled 'Flow Percentage vs Depth' showing a steady increase from near 0%, a slight rise around 18 units, a significant jump around 28 units, and reaching 100% near 48 units.