Calculator
Pond volume and desilting calculator
Enter the pond's size at the top, its depth and side slope. The calculator gives the storage, how much earth to dig, and whether the catchment around it can fill it in a normal year.
Your pond
How the volume is calculated
A pond with sloping sides is a frustum: smaller at the bottom than at the top. Its volume uses the prismoidal formula, V = h ÷ 6 × (top area + 4 × middle area + bottom area), where each side shrinks by the slope × depth on both sides.
Inflow a year = catchment area × runoff factor × rainfall, plus rain falling on the pond itself. If the inflow is less than the storage, the pond will not fill in a normal year.
Check the numbers for your area
Frequently asked questions
How much water does a 1 acre pond hold?
A 1 acre pond (about 64 × 64 m at the top) with 3 m of water and 2 : 1 side slopes stores about 9,400 m³, or 94 lakh litres.
How do I calculate desilting quantity?
Measure the bed level at several points, take the average depth of silt to be removed and multiply by the bed area. For a full redesign, the digging volume shown here is the earthwork from ground level to the new bottom.
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