Gully / inlet spacing module

Inputs

• Corridor width and slopes (cross and longitudinal)
• Roughness coefficient(s)
• Allowable spread constraints
• Segment discretization/spacing assumptions

Steps

1. Define the road drainage segment/profile.
2. Enter hydrology inputs for contributing runoff (or reference previously computed \(Q\)).
3. Run gully spacing logic and review:
4. spread
5. required inlet length and capture efficiency
6. bypass progression
7. Run sag checks where applicable and compute required inlet counts.

Review checklist

• Spread is within allowable constraints.
• Capture efficiency is consistent with inlet length and flow.
• Bypass does not grow unexpectedly between successive segments.