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Irrigation Water-Balance Calculator
Track soil moisture depletion against your trigger threshold to see when — and how much — to irrigate.
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Result
How it's calculated
Total available water (TAW, in) = AWC (in/ft) × root-zone depth (ft). The trigger threshold is TAW × MAD%. Water used since the last full point = crop ET × days − rainfall. Once used water reaches the trigger, it's time to irrigate — refill to (roughly) the amount depleted.
This is a single snapshot, not a running season log — Row Wise's own water-balance model tracks this day by day automatically from your field's real weather and a crop-stage-aware ET curve, so the checkbook never resets to a guess.
Row Wise runs this water balance automatically every day per field — real ET0, SSURGO soil data, and a stage-aware crop coefficient — so you never have to log it by hand.
Get notified at launch →Frequently asked questions
What is management allowed depletion (MAD)?
MAD is the percentage of total available water you let the crop use before you irrigate — commonly 40–55% for most row crops. A lower MAD means you irrigate sooner and more often; a higher MAD stretches intervals but risks stress near the trigger point.
How do I find my soil's available water capacity (AWC)?
AWC depends on soil texture — sandy soils hold about 0.6–1.0 in/ft, loams 1.5–2.0 in/ft, and clay loams 2.0+ in/ft. Your county's SSURGO soil survey (or the preset buttons here) gives a reasonable starting figure.
Why does effective root zone depth matter?
A shallow root zone (young crop, or a restrictive layer) holds much less total water than a full, mature root system — so the same soil triggers irrigation far sooner early in the season than at peak root depth.