Changeset: 145344378
this river is above 4m wide
Closed by StreamMaps
Tags
changesets_count | 38 |
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created_by | iD 2.27.3 |
host | https://www.openstreetmap.org/edit |
ideditor:walkthrough_progress | welcome;startEditing;navigation |
ideditor:walkthrough_started | yes |
imagery_used | Orthophoto (2016–2018), 1:5000, Latvia |
locale | en-GB |
Discussion
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Comment from HellMap
Hi!
Thanks for your changes!
However, I had to correct the waterway back to a stream. This is not a river in OSM tagging sense, regardless of its historical name or width or historical local designation. Many semi-artificial streams, even based on historical streambeds and riverbeds are only streams nowadays. This one simply semi-artificially router the water around developed areas. To add, a river cannot terminate in a waterway that is lesser than itself. And this stream ends up in a canal running parallel to the dam. If it had the characteristics of a river, it would end up in Daugava or overflow otherwise.
Thanks
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Comment from StreamMaps
Hi hellmap, from what I've read from osm a river is considered a body of water that cannot be jumped across by an adult man (around 3m) this stream/river is around 4-5m wide and cannot be jumped across. This stream/river appears on pre soviet era maps (meaning pre flooding of lands next to the Daugava river due to the hes) showing it's Natural course flowing into the Daugava river, i also believe this river/stream is natural due to it's early appearance on maps and it's course appearing natural and the large number of tributerys, there are also other nearby rivers witch have the same property's such as Bļuķupe witch os a river with close to the same water level and same destination yet is still considered a river.
let me know what you think of this,
Thanks -
Comment from HellMap
OSM Wiki describes the general approach. Because there is so much variation in the world, it's only an approximate guideline. The goal is to describe the functional purpose of the element. "Jumping across" is a good indication that something might be a river, but that doesn't mean so - it can be a canal, a drain or large ditch or indeed a stream. We have to look at how it compares to other rivers across Latvia. And this example is different than typical due to HES. Here it fails two of the main criteria - it's not a significant flowing body of water and it doesn't actually flow into anything. It doesn't flow into Daugava, it ends at the canal and it doesn't even feed the canal much. Most of the stream is wide exactly because it doesn't flow - the water just accumulates because it has nowhere to go. And it has nowhere to go because nowadays these are all just large melioration ditches that follow some of the original waterways. This is why there are ponds and small lakes here - it's where the water ends up. And we only tagged this as a stream because it's larger here when fed by ditches and not being able to flow anywhere. But that's a long way from a river for what is just a big ditch. It was tagged as a ditch for a decade before another local mapper began changing these.
You can find many examples of several meter wide ditches, like https://www.openstreetmap.org/way/1029646110 , but these aren't rivers unless they actually form the primary ways for a tributary network and serve as the outflow for it.
Bluķupe should not be a river either. It was changed recently and it is a similar mistake. No one just noticed it. That one is even smaller than this one.
As I mentioned, historic local classification is not the same as the current real-world status, so that wouldn't matter. And more importantly other maps don't necessarily match OSM meanings for such things. Soviet maps used to call pretty much any named long natural waterway a river.
Similarly, original flow of the waterway before HES or area development wouldn't really matter. As I mentioned, it is semi-artificial - some of it matches the original layout, but much of it has been "straightened" around areas. And historical streambeds and riverbeds do not determine the current status.
Anyway, those are my thought on this because I have looked at this location before and surveyed the area around. I do not believe it comes anywhere close to a river classification because it is a large ditch that is probably ok to call a stream due to its appearance.
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Comment from StreamMaps
Hi hellmap,I disagree with your point of view for several compelling reasons:
1. Continuity Despite Alterations: Numerous rivers globally have undergone artificial course changes and remain recognized as the same river. Modifying a section of the course doesn't fundamentally alter the identity of the river.
2. Extensive Tributary Network:After surveying the area, including a visit just three hours ago, I saw an intricate tributary network. Multiple small streams and ditches flow into the river, each with their own smaller tributaries, showcasing a complex hydrological system.
3. Decent Flow Indicators: In specific sections, the river exhibits a noticeable narrowing and increased water visibility, indicating a substantial flow that aligns with the characteristics often associated with small rivers.
4. Ambiguity in River Definition:The lack of a universally clear-cut definition for a river leads to varied interpretations. Given the absence of a precise definition, this rivers features and contributions make a compelling case for its classification as a river.
5. Impact on Canal and Downstream: this rivrr significantly influences the canal, serving as its primary water source. This, in turn, plays a crucial role in sustaining Dārziņu Ateca.
6. Consistency Over Time:While historical significance might not be a direct classification factor, the continuity of this rivers characteristics over a century underscores its identity as the same river/stream, despite changes in mapping conventions.
7. Artificial Changes with Daugava Connection: Despite artificial alterations redirecting the river away from the Daugava, its waters still ultimately find their way into the Daugava river, highlighting a historical connection.
8. Distinguishing Natural Origin:* this river and its tributaries predominantly originate from natural springs, maintaining a connection to its natural origin. Even minor contributions from man-made sources don't negate its overall natural character.
In summary, while acknowledging the existence of smaller ditches, the evidence supports the classification of the river as a river, falling within the spectrum of small rivers, especially considering its natural spring origin and the intricate network it sustains.
Thanks (btw this took my a long time to make lol)
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Comment from HellMap
I asked the community at https://osmlatvija.zulipchat.com/#narrow/stream/358602-general/topic/Salaspils.20.C5.ABdensteka although we don't have that many mappers in Latvia, so it might not get many answers.
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Comment from StreamMaps
Great, unfortunately we don't have many mappers in latvia but it's great to have other mappers in this region so it's easier to verify and double check information, btw i have some images of the river and some old maps witch are revelent but idk how to send them
Ways (1)
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