Examples
Examples
Try the starting example
- Drain horizontal run (m)
- 12
- Specified gradient (percent)
- 2
- Starting invert elevation (m)
- 100
- Required fall (mm)
- 240
- Ending invert elevation (m)
- 99.76
- Gradient as one-in-N
- 50
Try another scenario
- Drain horizontal run (m)
- 13
- Specified gradient (percent)
- 2
- Starting invert elevation (m)
- 100
- Required fall (mm)
- 260
- Ending invert elevation (m)
- 99.74
- Gradient as one-in-N
- 50
Calculation method
Calculation method
Required fall (mm)
Fall = horizontal run × percent/100; subtract from starting invert.
Ending invert elevation (m)
Fall = horizontal run × percent/100; subtract from starting invert.
Gradient as one-in-N
Fall = horizontal run × percent/100; subtract from starting invert.
Symbols and units
- a
- Drain horizontal run (m)
- b
- Specified gradient (percent)
- c
- Starting invert elevation (m)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions & limits
Assumptions & limits
- User-supplied measurements and assumptions; Fall = horizontal run × percent/100; subtract from starting invert. Supported limits: Finite numeric values bounded to 1e9 magnitude; lists and tables contain 1–100 records unless a stricter bound is stated. Inputs use the units shown. Lists explicitly paired by a method must have matching lengths; independent polynomial coefficient vectors may differ. Respect stated physical, interpolation, policy and computational domain limits.
Are these inputs private?
These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.