That definition got a big “whatever” from my side when I first read it. To this day, I don’t understand why would anyone want to distinguish waterways by lining of their banks.
I typically map the countryside of my province, most of which is arable land on former floodplains, and thus laden with irrigation and draining systems. As SomeoneElse indicated, I use the following rules of thumb to distinguish artificial waterways:
- ditch - a small waterway. Usually easy to cross by foot, but not by a vehicle. Typically intermittent (dry in summer), so much that I’m bothered by having
intermittent=yeswith those, since it’s so by definition. - drain - larger waterway. Typically contains water year-round. Hard or impossible to jump over, but not wide/deep enough to support any vessel other than a light kayak. Sometimes named, but always has a
refin the public water management company inventory. - canal - larger still, with water year-round. Supports at least boat-sized vessels. Virtually always has a name and a
ref.
And then, there are hard cases when former river beds and oxbow lakes have been reused as drains or canals (recognizable by curved shapes), or existing rivers and streams re-channelized into man-made structures. I deal with those case-by-case (as a drain, canal, stream or river), and not always consistently.
Perhaps I’m being idiosyncratic, but I believe this or a similar approach is more frequently used worldwide. However, I’m admittedly lazy to investigate and perhaps change the Wiki articles.