> For the complete documentation index, see [llms.txt](https://swatplus.gitbook.io/io-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://swatplus.gitbook.io/io-docs/introduction-1/channels/hyd-sed-lte.cha/wd_rto.md).

# sinu

Channel sinuosity is a measure of how much a river or stream channel deviates from a straight line between two points. It is calculated by dividing the length of the channel by the straight-line distance between its endpoints. 

For rivers, the conventional classes of sinuosity are:

| Sinuosity       | Channel Form    |
| --------------- | --------------- |
| < 1.05          | almost straight |
| ≥ 1.05 - < 1.25 | winding         |
| ≥ 1.25 - < 1.50 | twisty          |
| ≥ 1.50          | meandering      |