Proposal talk:Qanat

location=underground

I think that adding location=underground should be recommended Mateusz Konieczny (talk) 22:16, 27 April 2019 (UTC)

Isn't it implied by tunnel=flooded? Thanks for your interest. There was limited response on the tagging list, which is why I didn't go to voting. JoeG (talk) 23:32, 27 April 2019 (UTC)

Good question. Maybe it is sufficient, but I wonder whatever tunnel=flooded can be potentially used also for enclosed water pipes in aqueducts Mateusz Konieczny (talk)

I see. To me, a tunnel is always covered, so yes, an enclosed pipe could maybe be tagged as tunnel=flooded even if above ground. In my opinion this is a corner case, so location=overground would be added, with most tunnels assumed by default to be location=underground

The key location=* does say: "For features which are contained within a self-supporting tunnel, which may also be used for other purposes or provided for maintenance purposes, use tunnel=* instead"

However, my intention was to follow the revised waterway tagging as closely as possible and tunnel=flooded does mention using location=underground. I've therefore copied the same language onto this page. Thank for highlighting the gap! JoeG (talk) 22:03, 28 April 2019 (UTC)

I'm strictly against adding implicit tags. location=underground is not needed since Qanats are underground by definition.--Buraq (talk) 16:46, 14 May 2019 (UTC)

Thanks for the comment, Buraq. There are two issues here. 1) regardless of how the word qanat is used in reality, the tag canal=qanat applies to both the underground and open-air parts, as described in the proposal. However, it is true that any underground qanat will be marked as tunnel=flooded already, which usually implies underground (as noted above). 2) we should not deviate from how waterway=canal deals with this issue. If we want to ban the use of location=underground on qanats, it should be banned on waterway=canal +tunnel=flooded generally. Personally I agree with you and I won't be using location=underground, but I don't think the text description should ban it. - JoeG (talk) 21:05, 14 May 2019 (UTC)

I don't see any need for using location=* together with tunnel=*, so it is now removed from the proposal. Also, since a qanat is defined by the underground features, it makes sense to use this tag for the underground portions of a qanat. The above-ground portion of canal after the qanat is not clearly different than any other irrigation canal. --Jeisenbe (talk) 18:35, 19 June 2020 (UTC)

My argument would be that the above ground portion of a qanat is distinctive simply because it is connected to the below ground part. It doesn't make sense to prevent canal=qanat being applied to the above ground part. Note that tunnel=flooded only implies an enclosed space, not necessarily completely underground, and that that it also optionally allows the use of location=underground. I suggest we keep it optional here too for consistency. --JoeG (talk) 22:23, 19 June 2020 (UTC)

Creating page on main wiki

Anybody have any objection to creating a page for canal=qanat in the main wiki name space? The less favoured man_made=qanat is already there, which makes it look like it's recommended.

I would mark this page's status as undefined, and the main page's status as proposed? There doesn't seem to be enough interest for official voting to be worthwhile.

JoeG (talk) 22:15, 28 April 2019 (UTC)

"Anybody have any objection to creating a page for canal=qanat in the main wiki name space?" - it sounds OK for me, especially given that man_made=qanat got created Mateusz Konieczny (talk) 07:08, 29 April 2019 (UTC)

Voting on this proposal

Since the tag man_made=qanat is also being used, I think we should vote on approving this tag. I prefer this method, because it makes it clear that a qanat is a type of man-made waterway, like other canals and aqueducts. Does anyone object if I update this proposal and bring it to a vote? --Jeisenbe (talk) 16:30, 18 June 2020 (UTC)

Please do! I hadn't brought it to a vote because of low interest on the mailing list, but this might change given the alternative tag has seen much greater usage than this once since then --JoeG (talk) 22:42, 18 June 2020 (UTC)

Thanks for the great update! I noticed four issues:

• The whole length of a qanat is not necessarily underground, usually the end part is above ground. This wasn't entirely clear in the previous draft, but was the reason that that a qanat was not required to be exclusively underground. We need to be clear that canal=qanat does apply to that part of the structure too.
• Location=underground was explicitly brought up in discussion (above), but it seems has now been removed. It would be worth at least discussing this in the page because it will be a recurring issue.
• I think it may still be worth noting that some qanats are tourism=attraction (and not necessarily historic ones)
• I've now added a link to the discussion in September 2018

--JoeG (talk) 22:15, 19 June 2020 (UTC)

I have slight preference to man_made=qanat as it allows tagging dry quanats (is it actually a valuable use and real usecase?) Mateusz Konieczny (talk) 08:49, 21 June 2020 (UTC)

I would suggest disused:waterway=canal or abandoned:waterway=canal in the case that the qanat is disused or abandoned. --Jeisenbe (talk) 20:03, 22 June 2020 (UTC)

Right, makes sense. I will happily vote on whatever key/value will end in the final proposal (I have no preferences for either one) Mateusz Konieczny (talk) 21:44, 22 June 2020 (UTC)

Shouldn't usage=* be added?

Thank you for this proposal, it's an interesting topic.
I'm wondering if we don't miss a usage=* here?
I see two possibilities:

• Qanat is a particular usage and then canal=qanat should be moved to usage=qanat
• usage=gathering (currently specific to pipelines but adaptable to qanat) is suitable for collecting section and usage=transmission is suitable for transmission section (if known)

Many values of canal=* confuse with usage=* and it would be good to be sure it's the best key to use here. All the best Fanfouer (talk) 18:04, 18 June 2020 (UTC)

waterway=canal already specifies the use of usage, so I definitely wouldn't want to use usage=qanat. However, usage=transmission and usage=gathering do make sense. I would suggest making them optional, because one of the two is already implied by the canal type. --JoeG (talk) 23:18, 18 June 2020 (UTC)

A qanat is a particular type of canal construction: a free-flow, mostly underground aqueduct which is dug with vertical shafts along it's course, and the source is groundwater. The water might be for irrigation or drinking water. I would say that it's reasonable to also add usage=* when known, but usage=qanat does not make sense. --Jeisenbe (talk) 17:18, 19 June 2020 (UTC)

Well, ok to focus on usage=transmission and usage=gathering.

The most common usage of a qanat would be usage=irrigation - they are not used for long-distance transimission of water to other places, but usually just a few kilometers to a village. They do not gather water, they basically bring it from a "well" (an underground well) at the head of the channel. Some might be usage=drinking_water or usage=household_water or whatever you want to call that - same as an aqueduct to a town, though in most cases they are for irrigating cropland or orchards. But this is not part of the proposal... --Jeisenbe (talk) 05:20, 21 June 2020 (UTC)

What would be other construction to use in canal=* ? canal=irrigation => usage=irrigation, canal=leat => What is a leat ? Fanfouer (talk) 21:32, 20 June 2020 (UTC)

Let's use canal=* for the construction and form of the canal. Other significant types would be canal=leat which is a millrace: https://en.wikipedia.org/wiki/Leat - probably the more common English word canal=millrace would be best. There are also significant types in other areas, like canal=levada - https://en.wikipedia.org/wiki/Levada - narrow irrigation channels found in Portugese-influenced areas, e.g. Madeira. Yet another type of specialized waterwa would be a flume - https://en.wikipedia.org/wiki/Flume - though these are becoming rare now days. And I think we could use canal=aqueduct - In a restricted sense, aqueducts are structures used to conduct a water stream across a hollow or valley. Though there is a risk of confusion since in some dialects any waterway=canal is also an aqueduct, so we would have to be careful about that.

But all of that is discussion for another proposal. This proposal is just deciding whether we should use canal=qanat or man_made=qanat with waterway=canal for these particular features. Let's keep it simple, please. --Jeisenbe (talk) 05:20, 21 June 2020 (UTC)

usage=gathering currently refers to pipelines taking oil/gas/whatever from well heads to a processing substations. I see a clear similarity with parts of qanat going from its source to the point it goes out the aquifer. Ok to use usage=irrigation elsewhere.

Millrace is not a structure and is currently described by usage: usage=headrace (+ usage=penstock +) usage=tailrace.

Can you provide a relevent difference between canal=leat (https://en.wikipedia.org/wiki/Leat) and waterway=ditch please?

This proposal introduces a strong usage of currently cluttered canal=*. To know if it's the best possibility and which is its best definition is clearly a question to answer now. It's a major element to decide how it can be extended in a further proposal without changing its definition or simply use it in another activities Fanfouer (talk) 11:22, 21 June 2020 (UTC)

How should we tag qanat shafts?

The proposal (and current database usage) suggest to tag the excavation / maintenace shafts along the qanat with the tags man_made=excavation + excavation=qanat_shaft. The first tag (man_made=excavation) is only used for this purpose currently, though it seems more general. Any problems with including this in the proposal for approval? --Jeisenbe (talk) 18:33, 19 June 2020 (UTC)

man_made=shaft should be considered as well. Example for a 200m depth pipeline surge tank 544903577 544903577. Fanfouer (talk) 11:25, 21 June 2020 (UTC)