On Sun, 3 Feb 2019 at 10:53, Eugene Podshivalov <yauge...@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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