[Tagging] Drain vs ditch

[Eugene Podshivalov]

вс, 3 февр. 2019 г. в 16:38, Paul Allen <pla16021 at gmail.com>:

> Yes, we could switch to calling them all drains and then adding
> lined=yes/no, but we already
> have ditch and drain.  I think it's better to fix the wiki than do that.

If it was to select just one tag for the two notions, I would choose
"ditch", not "drain".
Most of ditches are drainage ditches, hence usage=drain can be assumed by
default if not defined, but renaming irrigation ditches into
drains+usage=irrigation sounds incorrect.

Cheers,
Eugene

вс, 3 февр. 2019 г. в 16:38, Paul Allen <pla16021 at gmail.com>:

> On Sun, 3 Feb 2019 at 10:53, Eugene Podshivalov <yaugenka at gmail.com>
> wrote:
>
>>
>> There are distinctions between these two terms, otherwise they would not
>> be defined separately.
>> In simple words, a ditch is a small open-air man-made or self-formed
>> channel in the ground for absolutely any purpose, both lined or unlined
>> entirely or partially.
>>
>
> Ummmm, maybe.  Maybe not.
>
> Part of the problem, of course, is that English dictionaries are
> descriptive, not proscriptive:
> if words are misused in English frequently enough, that misuse becomes one
> of the word's
> meanings (which is why "cleave" is its own antonym).  The fact that
> "ditch" and "drain" are
> often used interchangeably these days doesn't mean that there isn't a
> meaningful
> distinction.
>
> See https://en.wikipedia.org/wiki/Ditch and
> https://english.stackexchange.com/questions/190527/difference-between-ditch-trench-and-gutter
> - a ditch is a simple, unlined trench for the purpose
> of drainage or irrigation.  A salient characteristic is that it is
> unlined.  It is used to drain (mainly)
> agricultural fields with a high water table.  The fact that it is unlined
> means that water can seep
> through the side of the ditch and then flow away.  A lined ditch would not
> work (only water above
> the lining could seep into the ditch rather than across the whole height
> of the ditch).  Irrigation
> is the same thing in reverse - a lined ditch wouldn't work as well.
>
> A drain is lined to *prevent* seepage.  At its smallest, it is a roadside
> gutter (open drain) which
> usually has frequent openings to underground drains.  Or it may be a small
> channel.  The
> distinction between a drain and a canal is one we can spend months arguing
> about. :)
>
> From everything said here and everything I've found on the internet I'd
> say that lined/unlined
> is the only distinguishing characteristic between ditch and drain.  Size
> is irrelevant.  There
> is a real difference in purpose and on-the-ground appearance between a
> channel
> designed to allow seepage to/from the land it passes through and one that
> is not.
>
> Yes, some mis-tagging is inevitable.  If you're using aerial imagery it's
> hard to tell if
> something is lined or unlined.  Or even if it's part of a stream that has
> been artificially
> straightened. But you can make a fairly good guess in most instances.  We
> also have
> to acknowledge that we rarely achieve perfection but do the best we can
> and hope any errors
> are corrected later.  If we throw away the distinction (they're all
> drains) it will be harder to
> fix than if we keep the distinction and realize that there will be
> occasional errors.
>
> Yes, we could switch to calling them all drains and then adding
> lined=yes/no, but we already
> have ditch and drain.  I think it's better to fix the wiki than do that.
>
> --
> Paul
>
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