Water Addition Calculator
Calculate how much water to add to raise the moisture content of a compost mixture (or any pile).
Step 1: Enter Amount of Material on the Pile
Typical: yard waste 400–600, food waste 1,200–1,800, finished compost 800–1,100, mixed feedstock 700–1,000 lbs/CY
Step 2: Enter Moisture Content
Formula Reference
Qwater = W × (Mf − Mi) / (1 − Mf)
Where: W = as-is (wet) weight of material, Mi = initial moisture content (decimal), Mf = target moisture content (decimal), Qwater = weight of water to add.
Assumption: Water density = 62.4 lbs/ft³ (8.34 lbs/gallon at ~60 °F). Gallon conversion uses Qgallons = Qwater / 8.34.
Assumption: Water density = 62.4 lbs/ft³ (8.34 lbs/gallon at ~60 °F). Gallon conversion uses Qgallons = Qwater / 8.34.
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