Required Drainage System Capacity: – cfs
The Drainage Coefficient Calculator helps determine the required drainage system capacity for agricultural or land management applications. The drainage coefficient represents the depth of water that must be removed from the land within 24 hours. By using this calculator, users can design effective drainage systems that prevent waterlogging and ensure proper soil conditions for crops and vegetation.
Formula of Drainage Coefficient Calculator
The required drainage system capacity (Q) is calculated using the formula:
Q = A × DC × 0.042
Where: Q = Required drainage system capacity (cubic feet per second, cfs)
A = Drainage area (acres)
DC = Drainage coefficient (inches per 24 hours)
0.042 = Conversion factor from acre-inches per 24 hours to cfs
Pre-calculated Drainage System Capacity Table
This table provides estimated drainage system capacities for commonly used values, making it easier for users to determine the required drainage capacity without manual calculations.
| Drainage Area (acres) | Drainage Coefficient (inches/24 hours) | Required Capacity (cfs) |
|---|---|---|
| 10 | 0.25 | 0.105 |
| 20 | 0.5 | 0.42 |
| 50 | 0.75 | 1.575 |
| 100 | 1.0 | 4.2 |
| 200 | 1.5 | 12.6 |
This table serves as a quick reference for engineers, farmers, and land managers designing drainage systems.
Example of Drainage Coefficient Calculator
Let's assume a land area with:
- Drainage area (A) = 50 acres
- Drainage coefficient (DC) = 0.75 inches per 24 hours
Using the formula:
Q = 50 × 0.75 × 0.042
Q = 1.575 cfs
This means the drainage system must have a capacity of at least 1.575 cubic feet per second to effectively remove excess water.
Most Common FAQs
The drainage coefficient helps determine the required capacity of a drainage system, ensuring proper water removal to prevent flooding and soil damage.
Soil type, land slope, rainfall patterns, and crop type all influence the drainage coefficient, requiring adjustments for different conditions.
This calculator is mainly for agricultural and land management applications, but similar principles apply to urban drainage with modified calculations.