Watering and Irrigation
Effective Rainfall Calculator
Use Effective Rainfall when you need to estimate rainfall retained for garden use after losses. It calculates effective rainfall from the measurements shown below.
Enter values for effective rainfall
Replace the Effective Rainfall examples before using effective rainfall.
Arithmetic used for Effective Rainfall
Effective Rainfall finds a difference among Measured rainfall and Runoff and loss before applying its division.
The example result is 0.77 in when measured rainfall at 1.1 in and runoff and loss at 30%. The calculation for replacement depth remains in Soil Moisture Replacement Calculator.
Effective rainfall: interpretation
Use Effective rainfall to estimate rainfall retained for garden use after losses. Keep the Effective Rainfall inputs beside the output.
Rainfall lost supplements effective rainfall in Effective Rainfall.
Effective Rainfall beyond the formula
Intense storms can produce more runoff than the entered average.
For Effective Rainfall, verify the basis of Runoff and loss. Similar percentages can describe different totals.
Measured rainfall and the other inputs
For effective rainfall, collect Measured rainfall and Runoff and loss on the Effective Rainfall basis.
- Measured rainfall. Effective Rainfall currently demonstrates 1.1 in; substitute the observation being evaluated.
- Runoff and loss. Effective Rainfall enters 30% for this percentage.
Field notes for Effective Rainfall
Measure delivery at normal operating pressure and note the zone being tested. Nominal flow is not a substitute for a catch-can or timed-volume check.
What Effective Rainfall answers
Effective Rainfall focuses on Effective rainfall and combines Measured rainfall and Runoff and loss.
Use effective rainfall to estimate rainfall retained for garden use after losses, then inspect measured rainfall in the field.
Measured rainfall source record
Store the Effective Rainfall date, Measured rainfall and Runoff and loss, and Effective rainfall.
Separate measured measured rainfall from an assumed value so a later user can reconstruct the case.
Add the garden outcome as a new entry, using the same units and definition as effective rainfall.
Questions about Effective Rainfall
How does “Intense storms can produce more runoff than the entered average.” affect effective rainfall?
No automatic adjustment is applied for it. Use a site-specific value for measured rainfall when the condition is present.
How should rainfall be handled in Effective Rainfall?
Use only the effective rainfall quantity named by Effective Rainfall. Keep gross rainfall and irrigation delivery as separate records.
Does Runoff and loss use percent or decimal form?
Enter Runoff and loss as a percentage in Effective Rainfall; 25 means 25 percent.