Drainage Capacity Calculator

Estimate required drainage flow using rainfall intensity, runoff coefficient, and field area. Results are shown in cubic feet per second (cfs).

Inputs

How It Works

Q = C × I × A × 1.008

Where:
C = Runoff coefficient
I = Rainfall intensity (in/hr)
A = Area (acres)

1.008 converts acre-inches/hour to cubic feet per second.

Related Calculators

Field Slope Topsoil Loss (USLE) Water Application Depth

FAQ

What is a runoff coefficient?

The runoff coefficient represents the fraction of rainfall that becomes surface runoff. Higher values mean less infiltration.

What affects drainage capacity?

Soil type, slope, rainfall intensity, crop cover, and conservation practices all influence drainage needs.

Why measure drainage capacity?

Proper drainage prevents ponding, root damage, delayed planting, and erosion issues.

About Drainage Capacity

Drainage capacity determines how quickly excess water can be removed from a field during heavy rainfall events. Insufficient drainage can lead to soil saturation, compaction, and yield loss.

Designing proper drainage systems requires estimating runoff volume and peak flow rates. This calculator provides a simplified estimate useful for planning and evaluation.