Culvert module

Inputs

• Design discharge \(Q\) (selected catchment + return period)
• Culvert geometry and constraints (shape, slope, length, invert levels)
• Inlet type parameters (as applicable)
• Roughness and loss assumptions (as applicable)

Steps

1. Select culvert location/row and set design discharge.
2. Use combination suggestion (if available) to select candidate culvert sizes.
3. Run culvert hydraulics:
4. inlet control \(H/D\)
5. outlet control \(H/D\)
6. governing \(H/D\) and control type
7. Review outlet velocity and protection sizing proxy (riprap).

Review checklist

• Governing control type is plausible for the slope/length/inlet condition.
• Governing \(H/D\) meets project limits.
• Outlet velocities and protection sizing are reasonable for the discharge.