Hydrology
TR-55 time of concentration with a clean PDF report in seconds.
Enter sheet flow, shallow concentrated flow and as many channel segments as you need, and get the TR-55 time of concentration back with a formatted PDF that echoes every input, so the calculation documents itself.
Time of Concentration
Free with an account
How it works
- Fill in the project header and flow segments.
- Calculate.
- Download the Tc report PDF.
What goes in, what comes out
You provide
- Project header text
Description, Designer, Project No., Location. - Sheet-flow parameters numbers
Manning's n, length (≤ 100 ft), 2-yr/24-hr rainfall, slope. - Shallow concentrated flow numbers
Paved/Unpaved surface, length, watercourse slope. - Channel flow segments table
One row per channel reach: Z, B, depth, slope, n, length.
You get
- Tc calculation report .pdf
A formatted PDF showing t₁ (sheet), t₂ (shallow), t₃ (channel), and the final Tc in hours, with all inputs echoed so the report is self-documenting.