[Tagging] Irrigation: ditches, canals and drains

[Martin Koppenhoefer]

sent from a phone

> On 29. May 2019, at 03:37, Joseph Eisenberg <joseph.eisenberg at gmail.com> wrote:
> 
> What, then, should be the distinguishing characteristic between
> waterway=canal and waterway=ditch or =drain? Width or importance or
> navigability, or should we still mention the usage as the main
> difference?


IIRR ditches were seen without construction like steel or concrete, just a man made depression to channel water, while drains are required to have their borders (and maybe base) constructed.

Not sure about small rock-cut waterways  with massive impermeable sides, are these ditches or canals or drains?

Stating the usage explicitly might help interpretation of the data, or while we’re still mapping fragments of an incomplete network, although I would have guessed with a more mature mapping this could already be seen from looking at the network structure and flow directions?

What about the practical, human scale distinction we use for natural waterways (can be jumped over), wouldn’t it be equally interesting for man made waterways?
Is a canal you can jump over still a canal, or does size somehow come into the equation? Can there be draining canals, or are these always drains?

Cheers, Martin