(c) Examples - USDA

Record the flow rate, duration of irrigation, and area of the field irrigated. The flow rate in gpm or cfs can be entered in the appropriate column. Flow rate (gpm) Divide by. Conversion factor Flow rate (cfs) Multiply by Duration of irrigation (hr) Divide by Field Area (acres) Equals Gross Irrigation Depth (inches) {Example} 820 ÷ 449. 1.83 x ... ................
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