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Trench Drain Sizing Calculator
Calculate required trench drain size based on drainage area and rainfall intensity
Trench Properties
Drainage Area Properties
Total width of area draining to both sides of the trench (e.g., 20ft means 10ft on each side)
Outlet Configuration
Number of points where water exits the trench drain
Sizing Results
Capacity Assessment
unknown
Channel Utilization: 0.0%
Outlet Utilization: 0.0%
Flow Rates
Trench Capacity
0.00 cfs
Required Capacity
0.00 cfs
Flow Characteristics
Velocity
0.00 m/s
Flow Regime
subcriticalDrainage Area
200 sq ft (0.005 acres)
10 ft × 20 ft
Design Considerations
- Trench capacity should exceed expected runoff by at least 20%
- Flow velocity should be sufficient to prevent sediment accumulation
- Consider adding a safety factor for intense rainfall events
- Account for potential future changes in drainage patterns