[Tagging] waterway=wadi problem
Warin 61sundowner at gmail.com Sat Jan 17 21:27:13 UTC 2015 Less work if intermittent is simply used without the frequency extension .. thus: intermittent=yes/no/winter/spring/summer/autum/seasonal/ephemeral (default assumption of no) Note 'fall' = northern American english, 'autum' for english english ? Comments: An intermittent=winter may not flow every winter .. but it is 'expected' to flow in winter. This year the 'Todd River' flowed in central Australia, usually there is no folw, might flow evrey 5? years. As such it is 'ephemeral'. As it is called a 'River' by the locals and on maps and by the government so it is tagged in OSM. I looked at wadi ... but it does not match my understanding nor local use. There is continuing discussion regarding fords of intermittent waterways, but my feeling was a consensus was reached with respect to extending intermittent to: intermittent=yes/no/winter/spring/summer/autumn/seasonal/ephemeral (default assumption of no) To that end, I've edited the talk page for the intermittent tag at https://wiki.openstreetmap.org/wiki/Talk:Key:intermittent What would be the next step in working toward getting the actual wiki page for the intermittent tag updated without stepping on too many toes. I see that RicoZ has already made a change to the wiki page for waterway=wadi tagging that seem to be a result of this same tagging email thread. Thanks! Tod___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
No! Flood prone means that they are expected to be flooded from time to time. Nothing about the design. So you would have to tag also each wadi, each river and each lake because this area is covered with water? Maybe the terms “designed” and “expected” are missleading. But the question is: How can we distinguish between “normal water” and “flood water”. I think rivers – also intermittent rivers – belong to the first category. Also fords belong to the first category, because the defination of the ford is that here you cross water (and the water can be intermittent or not). This does no harm, thought it is quite “normal”. However, other objects like the house you are living in probably you do not want to be filled with water. If it is filled with water, this will not be a normal-life situation for you. If your house is for example in the nice city of Cologne (Germany) near the river “Rhein”, than perhaps at least a part of your house will be filled with water one time each year. So your house can be filled with water in a very regular way, nevertheless this is not nice for you. Your house belongs to the second category. I think the key flood_prone should be applied only for the second category. The wiki page of the flood_prone key is not really clear. But texts like Flooded roadways are often very dangerous to cross and many people die each year as a result. on the wiki page suggest the same thing. It’s not about the normal ford, where you know that there maybe you have to cross water and that normally you can do so without a big danger. It’s about the not-normal situations. as this may help routing software to avoid potentially hazardous crossings if there has been heavy rain. This seems to be the original idea of the tag. And it’s useful. In most western coutries, a heavy rain isn’t a big problem – there are well-working sewerage systems. But I assure you that there are other parts of the world where this is different. If you are living in Abidjan (Ivory Coast) and you want to travel during the rainy season during a rainfall than you know that there are many roads that are impassable: Maybe 20% of the paved routes can’t be used because the water reachs 1 or 2 meters. (But most roads are unpaved. And unpaved roads are evern worser when it’s raining ;-) I'd hope that the flood_prone tag would be applied to an area I think both tagging – on areas an on highways – can be useful. Both tagging are also present in the database. and best if the frequency is noted e.g. once every 100 years. Agree. (Though – every 100 years is a very risky description. At places where floods occure more often – for example once a year – predictions tend to be more reliable.) Again no. A ford may be continuously under water. E.G. a road that goes through a river .. where the river normally flows across the top of the road. Some fords may only have water in floods, others seasonally, and others continuously. That is what I said ;-) ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
The flood prone areas are not designed to let you cross a river Yes. I think that is exactly the important point and a very good description/criterion. flood_prone=yes for things that are _not_ designed to be flooded. And waterway=*, ford=* … for things that _are_ designed/expected to be flooded. Lukas Sommer 2015-01-20 4:09 GMT+00:00 johnw jo...@mac.com: I think using flood_prone on places designed to handle water (like a ford) is incorrect. The sections of a freeway that are closed off during flooding (a lane is closed because storm waters cannot properly drain away, or cuttings under train crossings with flood level markers because the road floods - both are flood prone, but their job isn’t to let you cross a waterway. Fords can be dangerous to cross in storms, but their job is to let you cross in the presence of water. The flood prone areas are not designed to let you cross a river, they just end up being flooded because of inadequate drainage. a ford https://goo.gl/maps/aBWlg flood prone (with a warning sign with lights when it is flooded) https://goo.gl/maps/9aFXV doesn’t seeing a ford automatically mean it’s flood prone? it handles river crossings ^_^ Javbw On Jan 20, 2015, at 8:38 AM, johnw jo...@mac.com wrote: Some part of road have concrete parts that are flood_prone during cyclone. How can we (or not) extend it to roads? access:conditional = no @ flood I'm using flood_prone=yes. With surface=concrete. But I was looking for some method to unify intermittent aspects of rivers and roads that are related when roads are crossing river or vice versa. the ford=* key might be useful. They suggest to also tag depth=0 if it is usually dry year round. I think this is the tag you are looking for, especially since the road section is designed to be submerged (the concrete sections) which means it is a ford (as emergency or very large vehicles, like a bulldozer, could still cross on the road). In San Diego, there are several large roads that are built with fords, as access lost during flood conditions is merely an inconvenience. I think this applies to any roadway *designed* to let you cross a river by going through it, even if it is low/dry most of the time (otherwise, floodwaters would easily destroy the crossing). Also, because of the wadi problem, i will be making up a new “wash” proposal - as it seems wadi is completely generic now. Javbw ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On 21/01/2015 10:03 AM, tagging-requ...@openstreetmap.org wrote: Date: Tue, 20 Jan 2015 14:43:16 + From: Lukas Sommersommer...@gmail.com To: Tag discussion, strategy and related tools tagging@openstreetmap.org Subject: Re: [Tagging] waterway=wadi problem Message-ID: CAFTrL-2fWKpTY-8RNU_0Qa7-gq6=9G3arS2JwOnt=5dqfot...@mail.gmail.com Content-Type: text/plain; charset=UTF-8 The flood prone areas are not designed to let you cross a river Yes. I think that is exactly the important point and a very good description/criterion. flood_prone=yes for things that are_not_ designed to be flooded. No! Flood prone means that they are expected to be flooded from time to time. Nothing about the design. I'd hope that the flood_prone tag would be applied to an area, and best if the frequency is noted e.g. once every 100 years. And waterway=*, ford=* … for things that_are_ designed/expected to be flooded. Again no. A ford may be continuously under water. E.G. a road that goes through a river .. where the river normally flows across the top of the road. Some fords may only have water in floods, others seasonally, and others continuously. Lukas Sommer ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
Some part of road have concrete parts that are flood_prone during cyclone. How can we (or not) extend it to roads? access:conditional = no @ flood I'm using flood_prone=yes. With surface=concrete. But I was looking for some method to unify intermittent aspects of rivers and roads that are related when roads are crossing river or vice versa. the ford=* key might be useful. They suggest to also tag depth=0 if it is usually dry year round. I think this is the tag you are looking for, especially since the road section is designed to be submerged (the concrete sections) which means it is a ford (as emergency or very large vehicles, like a bulldozer, could still cross on the road). In San Diego, there are several large roads that are built with fords, as access lost during flood conditions is merely an inconvenience. I think this applies to any roadway *designed* to let you cross a river by going through it, even if it is low/dry most of the time (otherwise, floodwaters would easily destroy the crossing). Also, because of the wadi problem, i will be making up a new “wash” proposal - as it seems wadi is completely generic now. Javbw ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
I think using flood_prone on places designed to handle water (like a ford) is incorrect. The sections of a freeway that are closed off during flooding (a lane is closed because storm waters cannot properly drain away, or cuttings under train crossings with flood level markers because the road floods - both are flood prone, but their job isn’t to let you cross a waterway. Fords can be dangerous to cross in storms, but their job is to let you cross in the presence of water. The flood prone areas are not designed to let you cross a river, they just end up being flooded because of inadequate drainage. a ford https://goo.gl/maps/aBWlg https://goo.gl/maps/aBWlg flood prone (with a warning sign with lights when it is flooded) https://goo.gl/maps/9aFXV https://goo.gl/maps/9aFXV doesn’t seeing a ford automatically mean it’s flood prone? it handles river crossings ^_^ Javbw On Jan 20, 2015, at 8:38 AM, johnw jo...@mac.com wrote: Some part of road have concrete parts that are flood_prone during cyclone. How can we (or not) extend it to roads? access:conditional = no @ flood I'm using flood_prone=yes. With surface=concrete. But I was looking for some method to unify intermittent aspects of rivers and roads that are related when roads are crossing river or vice versa. the ford=* key might be useful. They suggest to also tag depth=0 if it is usually dry year round. I think this is the tag you are looking for, especially since the road section is designed to be submerged (the concrete sections) which means it is a ford (as emergency or very large vehicles, like a bulldozer, could still cross on the road). In San Diego, there are several large roads that are built with fords, as access lost during flood conditions is merely an inconvenience. I think this applies to any roadway *designed* to let you cross a river by going through it, even if it is low/dry most of the time (otherwise, floodwaters would easily destroy the crossing). Also, because of the wadi problem, i will be making up a new “wash” proposal - as it seems wadi is completely generic now. Javbw ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
My main suggestion would be to re-use the same scheme as Key:opening_hours to define the time when the waterway is likely to flow. I would also discard rare/frequent as too subjective. Instead: approximate duration are not perfect but should improve mutual understanding. For instance as in: waterway = * + intermittent = yes | no | periodical | random (default:no) ++ intermittent:periodical = [opening_hours scheme] (likely to flow at this date) eg. Mar-Jun | OR | Nov 20-Feb 20 | OR | ... ++ intermittent:random:interval = [approximate duration] (typical/assumed duration between two flowing events) eg. 2 weeks | OR | 3 years | OR | ... ++ intermittent:random:duration = [approximate duration] (typical/assumed duration of one flowing event) eg. 12 hours | OR | 3 days | OR | ... I am sure some people would like to go in more details, so why not: + intermittent:origin = rain | snowmelt | geothermal | ... + intermittent:effect = stream | torrential | flood | ... Mateusz Konieczny matkoni...@gmail.com wrote: Please, no intermittent=ephemeral. Key intermittent was defined to have only a single valid value, turning it into free-form tag is a bad idea. Maybe intermittent=yes, intermittent:type=ephemeral? Maybe other tags began with a key and a single valid value. Afterwards they evolved to multiple valid values for added details and nuances. Multiple valid values [option1|option2|...|optionN] is not the same as free-form [name/note/source/description=*], is it? ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Sat, Jan 17, 2015 at 12:14:53PM -0800, Tod Fitch wrote: usually you will assume it if there are ponds of open water or swamps in several places along a valley. A pond/swamp/oasis/cienega in an arid or even semi-arid area is a significant feature that deserve mapping in its own right. Using that to infer information about a nearby or connected item seems a stretch to me. ponds and such should be mapped. Infering an underground waterflow from them may or may not be a stretch depending on the information that you have available. Often the underground waterflow is locally well known or can be inferred from many other informations. The more I think about this issue the more I am coming to the feeling that waterway=wadi ought to be deprecated and we should come up with a way of further defining intermittent to distinguish between seasonal and ephemeral flow patterns. Based on other responses on this thread maybe: that would be the best thing to do.. seems like otherwise every single mapper would use wadi in a different way. waterway=* intermittent=yes/no (default assumption of no) intermittent:frequency=winter/spring/summer/fall/seasonal/ephemeral/unknown (default assumption of unknown) +intermittent:frequency=random_rare/random_frequent ? We are still missing a definition of natural=valley afaics. There are some old proposals but I have been told on some other mailing list that valeys are nowadays mapped as a line natural=valley along the valley bottom. So maybe we should also document this or make a proposal to that effect. Richard ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
Please, no intermittent=ephemeral. Key intermittent was defined to have only a single valid value, turning it into free-form tag is a bad idea. Maybe intermittent=yes, intermittent:type=ephemeral? 2015-01-17 13:47 GMT+01:00 Richard Z. ricoz@gmail.com: On Fri, Jan 16, 2015 at 02:44:27PM -0800, Tod Fitch wrote: Since the current term wadi can mean something more than the actual watercourse, why not drop it and use ephemeral=yes or intermittent=ephemeral on waterway=* to indicate that it carries water much less often than a waterway tagged with intermittent=yes? in principle yes. We need a value to indicate that surface water is intermittent or rare but there is a persistent underground waterflow following the riverbed which is a frequent feature of wadi's (unlike washes where this seems rare) Richard ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Sat, Jan 17, 2015 at 07:50:36AM -0800, Tod Fitch wrote: Based on where I sometimes see old wind driven pumps, I'd guess that many longer (10s of miles long) washes have an underground flow. I think so. On the other hand, in the field or using Bing imagery neither I nor any other typical citizen mapper can really determine if there is unseen underground water flow. So so how can that be a criteria for mapping the feature? usually you will assume it if there are ponds of open water or swamps in several places along a valley. Richard ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Jan 17, 2015, at 11:52 AM, Richard Z. wrote: On Sat, Jan 17, 2015 at 07:50:36AM -0800, Tod Fitch wrote: Based on where I sometimes see old wind driven pumps, I'd guess that many longer (10s of miles long) washes have an underground flow. I think so. On the other hand, in the field or using Bing imagery neither I nor any other typical citizen mapper can really determine if there is unseen underground water flow. So so how can that be a criteria for mapping the feature? usually you will assume it if there are ponds of open water or swamps in several places along a valley. A pond/swamp/oasis/cienega in an arid or even semi-arid area is a significant feature that deserve mapping in its own right. Using that to infer information about a nearby or connected item seems a stretch to me. The more I think about this issue the more I am coming to the feeling that waterway=wadi ought to be deprecated and we should come up with a way of further defining intermittent to distinguish between seasonal and ephemeral flow patterns. Based on other responses on this thread maybe: waterway=* intermittent=yes/no (default assumption of no) intermittent:frequency=winter/spring/summer/fall/seasonal/ephemeral/unknown (default assumption of unknown) Tod ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Jan 17, 2015, at 1:41 PM, Steve Doerr wrote: On 17/01/2015 21:27, Warin wrote: Note 'fall' = northern American english, 'autum' for english english ? No, it's 'autumn' in British English. Comments: An intermittent=winter may not flow every winter .. but it is 'expected' to flow in winter. This year the 'Todd River' flowed in central Australia, usually there is no folw, might flow evrey 5? years. As such it is 'ephemeral'. 'Ephemeral' doesn't mean 'very rare'. It means 'lasting a very short time', theoretically just one day. Lasting a very short time properly describes the water flow in washes in southern Arizona and southern California. While fall is more commonly used in my part of the U.S., autumn (not autum) is not unheard of and well understood too. On Jan 17, 2015, at 1:27 PM, Warin wrote: On 18/01/2015 7:47 AM, tagging-requ...@openstreetmap.org wrote: Date: Sat, 17 Jan 2015 12:14:53 -0800 From: Tod Fitch t...@fitchdesign.com The more I think about this issue the more I am coming to the feeling that waterway=wadi ought to be deprecated and we should come up with a way of further defining intermittent to distinguish between seasonal and ephemeral flow patterns. Based on other responses on this thread maybe: waterway=* intermittent=yes/no (default assumption of no) intermittent:frequency=winter/spring/summer/fall/seasonal/ephemeral/unknown (default assumption of unknown) Tod Less work if intermittent is simply used without the frequency extension .. thus: intermittent=yes/no/winter/spring/summer/autum/seasonal/ephemeral (default assumption of no) Note 'fall' = northern American english, 'autum' for english english ? Comments: An intermittent=winter may not flow every winter .. but it is 'expected' to flow in winter. This year the 'Todd River' flowed in central Australia, usually there is no folw, might flow evrey 5? years. As such it is 'ephemeral'. As it is called a 'River' by the locals and on maps and by the government so it is tagged in OSM. I looked at wadi ... but it does not match my understanding nor local use. Putting everything as values on the intermittent tag would be fine with me, I was only reacting to: Mateusz Konieczny matkoniecz at gmail.com Sat Jan 17 13:28:00 UTC 2015 Please, no intermittent=ephemeral. Key intermittent was defined to have only a single valid value, turning it into free-form tag is a bad idea. Maybe intermittent=yes, intermittent:type=ephemeral? Cheers, Tod ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
Looking around in Wikipedia: Wash = Arroyo = Barranca = Wadi = Rambla = normally dry river bed, often subject to flash floods in case of upstream rain. If we have the the established term wadi for this, why create additional nearly synonymous tags? ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Thu, Jan 15, 2015 at 11:41:26AM +0900, johnw wrote: I strongly disagree. A wadi is usually only an active river through very rare flash flood events, and almost never any other time. Entire biomes are defined by the presence of (and situated in) a wadi. how about reading wikipedia? Wadi (Arabic: وادي wādī) is the Arabic term traditionally referring to a valley. In some cases, it may refer to a dry (ephemeral) riverbed that contains water only during times of heavy rain or simply an intermittent stream. I consider a wadi a geologic feature. In addition to the above wadis are expected to carry underground water. Richard ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
I now notice that I read the German Wikipedia entry for Wadi, which is plainly different form the English one. My fault. The English Wikipedia defines Wadi mainly as a valley, wheras the German on as a normally dry water course. On 16 January 2015 at 13:02, Richard Z. ricoz@gmail.com wrote: On Thu, Jan 15, 2015 at 11:41:26AM +0900, johnw wrote: I strongly disagree. A wadi is usually only an active river through very rare flash flood events, and almost never any other time. Entire biomes are defined by the presence of (and situated in) a wadi. how about reading wikipedia? Wadi (Arabic: وادي wādī) is the Arabic term traditionally referring to a valley. In some cases, it may refer to a dry (ephemeral) riverbed that contains water only during times of heavy rain or simply an intermittent stream. I consider a wadi a geologic feature. In addition to the above wadis are expected to carry underground water. Richard ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
Since we are supposed to use British English, I decided to look up wadi in my old paper edition of the Oxford English Dictionary (can we trust that more than Wikipedia?): Wadi or Wady [Arabic: وادي wādī] In certain Arabic speaking countries, a ravine or valley which in the rainy season becomes a watercourse; the stream or torrent running through such a ravine. Apparently first used in English literature in 1839 by the way. So it seems it could either be the valley or the actual intermittent watercourse. In that respect the term wash in the U.S. southwest is more specific as it is only applied to the intermittent watercourse. My impression from Southern California is that arroyo can be the valley/ravine as well as the actual watercourse, so that might match the OED definition of wadi more than wash does. Tod On Jan 16, 2015, at 5:36 AM, Volker Schmidt wrote: I now notice that I read the German Wikipedia entry for Wadi, which is plainly different form the English one. My fault. The English Wikipedia defines Wadi mainly as a valley, wheras the German on as a normally dry water course. On 16 January 2015 at 13:02, Richard Z. ricoz@gmail.com wrote: On Thu, Jan 15, 2015 at 11:41:26AM +0900, johnw wrote: I strongly disagree. A wadi is usually only an active river through very rare flash flood events, and almost never any other time. Entire biomes are defined by the presence of (and situated in) a wadi. how about reading wikipedia? Wadi (Arabic: وادي wādī) is the Arabic term traditionally referring to a valley. In some cases, it may refer to a dry (ephemeral) riverbed that contains water only during times of heavy rain or simply an intermittent stream. I consider a wadi a geologic feature. In addition to the above wadis are expected to carry underground water. Richard ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Fri, Jan 16, 2015 at 08:23:33AM -0800, Tod Fitch wrote: Since we are supposed to use British English, I decided to look up wadi in my old paper edition of the Oxford English Dictionary (can we trust that more than Wikipedia?): Wadi or Wady [Arabic: وادي wādī] In certain Arabic speaking countries, a ravine or valley which in the rainy season becomes a watercourse; the stream or torrent running through such a ravine. also http://en.wiktionary.org/wiki/%D9%88%D8%A7%D8%AF%D9%8A - valley. So it seems it could either be the valley or the actual intermittent watercourse. In that respect the term wash in the U.S. southwest is more specific as it is only applied to the intermittent watercourse. My impression from Southern California is that arroyo can be the valley/ravine as well as the actual watercourse, so that might match the OED definition of wadi more than wash does. I think we should look at how wadi is used in Arabic and decide if the feature is somehow interesting - and if the correct usage is compatible with prevalent usage in OSM https://www.google.de/search?q=%D9%88%D8%A7%D8%AF%D9%8Asafe=offhl=artbm=ischgbv=1sei=TlS5VKm5EOia7AbVvIDYCQ To me it looks too much like a synonym for valley, not sure if we need that. But maybe we need natural=valley? Richard ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
Since the current term wadi can mean something more than the actual watercourse, why not drop it and use ephemeral=yes or intermittent=ephemeral on waterway=* to indicate that it carries water much less often than a waterway tagged with intermittent=yes? ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
I would recommend expanding the definition of intermittent streams to include not only streams that have a regular, seasonal water flow but also streams in desert areas that exist only when a rare storm comes along. The topography is the same, the tendency of water to run downhill is the same, only the frequency of rainfall is different. -- John F. Eldredge -- j...@jfeldredge.com Darkness cannot drive out darkness; only light can do that. Hate cannot drive out hate; only love can do that. -- Martin Luther King, Jr. On January 15, 2015 3:13:38 AM Christoph Hormann chris_horm...@gmx.de wrote: On Thursday 15 January 2015, johnw wrote: A wadi is a place where flash floods occur. It is not an intermittent river - it isn’t really seasonally wet, and doesn’t provide any real expectation that water will be present (except deep underground) - because they are located in places where rain itself is unexpected for most of the year. Well - that would be a useful concept of a wadi but it has two problems: * current use of the tag is very different from that, you can see that quite well when you look at the taginfo map: https://taginfo.openstreetmap.org/tags/waterway=wadi#map the uses in Europe for example are probably almost always seasonal. * sporadic waterflow is very difficult to determine for the mapper. This is especially true for northern Africa where climate got a lot drier in the last few thousand years and as a result there are many permanently dry valleys that still look like being formed by waterflow but that have not seen significant waterflow in the last hundred years. My suggestion would probably be to stop rendering waterway=wadi in a way implying waterflow, encourage mappers to use intermittent/seasonal where this is known and reserve waterway=wadi - despite the then misleading key - for valleys where waterflow is unknown. -- Christoph Hormann http://www.imagico.de/ ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
as far as I am aware, a wash, an arroyo, and a wadi are functionally the same. It is mostly a separation of language - where the words wash, arroyo, and wadi are basically the same functional thing, however Wadi and arroyo, in some regions, also have a wider definition that includes other valley definitions. as it might be confusing to have three tags for the same thing (A lot of washes in California have Spanish names using the word Arroyo (“Arroyo Seco Del Diablo” ) and we have a de facto established tag with wadi, it seems like making three tags for the same functional item is overkill - as long as we preface that whatever it is being tagged functionally be a “wadi, not one in name only. That seems like a small caveat to avoid confusion between 3 tags. If avoiding that confusion at all costs means 3 tags, then lets make three tags - waterway=arroyo, waterway=wash, waterway=wadi and the different nuances between what really defines the tag can be spelled out on each page, and regional taggers can find a tag they are familiar with. I spelled out my definition of a wadi on the waterway=wadi talk page. http://wiki.openstreetmap.org/wiki/Talk:Tag:waterway%3Dwadi http://wiki.openstreetmap.org/wiki/Talk:Tag:waterway=wadi I look forward to further input, especially anyone who lives in a region with things called wadis - as my experience is with “washes in California. Javbw. On Jan 15, 2015, at 6:09 PM, Martin Koppenhoefer dieterdre...@gmail.com wrote: Am 15.01.2015 um 05:27 schrieb John Willis jo...@mac.com: I'm really surprised you were shot down from using wadi when it is the most applicable tag for the item, sometimes the most applicable tag is not sufficiently well describing/ distinguishing a feature and it is better to introduce a new tag that fits 100% To me, the Term wadi is quite specific for certain waterways that occur in a certain region of the world. We can decide whether we'd want to use it anyway everywhere for similar (or partly similar) features or if we introduce other, dedicated tags on the same level of specificity for these features. Why not having a tag waterway=wash, or are those really the same than a wadi? cheers, Martin ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Jan 15, 2015, at 6:13 PM, Christoph Hormann chris_horm...@gmx.de wrote: On Thursday 15 January 2015, johnw wrote: A wadi is a place where flash floods occur. It is not an intermittent river - it isn’t really seasonally wet, and doesn’t provide any real expectation that water will be present (except deep underground) - because they are located in places where rain itself is unexpected for most of the year. Well - that would be a useful concept of a wadi but it has two problems: * current use of the tag is very different from that, you can see that quite well when you look at the taginfo map: https://taginfo.openstreetmap.org/tags/waterway=wadi#map the uses in Europe for example are probably almost always seasonal. * sporadic waterflow is very difficult to determine for the mapper. This is especially true for northern Africa where climate got a lot drier in the last few thousand years and as a result there are many permanently dry valleys that still look like being formed by waterflow but that have not seen significant waterflow in the last hundred years. My suggestion would probably be to stop rendering waterway=wadi in a way implying waterflow, encourage mappers to use intermittent/seasonal where this is known and reserve waterway=wadi - despite the then misleading key - for valleys where waterflow is unknown. if it is the case that wadis are - not following my definition of a wadi - not currently tagged on wadis Then spitting off waterway=wash is the best idea, because - it is a defined geographic feature - is labeled and well known in the regions they exist, and are easy to tell apart to regional mappers. - and most importantly (to me) has a much different connotation than “intermittant stream” - more accurately describes the world as it exists. However all those tags in Africa and the Americas are probably correctly tagged. I bet cleanup of this tag will require some re-tagging, or a much broader definition of wadi - which would turn it into an intermittent or seasonal stream/river, so what’s the point of having the tag then… thanks for the useful data/map. -- Christoph Hormann http://www.imagico.de/ ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
Given the current discussion, I wonder if roads that are usually flooded during heavy rainfall should be also be tagged as waterway=river/stream and intermittent=yes. ;-) On Fri, Jan 16, 2015 at 7:27 AM, John F. Eldredge j...@jfeldredge.com wrote: I would recommend expanding the definition of intermittent streams to include not only streams that have a regular, seasonal water flow but also streams in desert areas that exist only when a rare storm comes along. The topography is the same, the tendency of water to run downhill is the same, only the frequency of rainfall is different. -- John F. Eldredge -- j...@jfeldredge.com Darkness cannot drive out darkness; only light can do that. Hate cannot drive out hate; only love can do that. -- Martin Luther King, Jr. On January 15, 2015 3:13:38 AM Christoph Hormann chris_horm...@gmx.de wrote: On Thursday 15 January 2015, johnw wrote: A wadi is a place where flash floods occur. It is not an intermittent river - it isn’t really seasonally wet, and doesn’t provide any real expectation that water will be present (except deep underground) - because they are located in places where rain itself is unexpected for most of the year. Well - that would be a useful concept of a wadi but it has two problems: * current use of the tag is very different from that, you can see that quite well when you look at the taginfo map: https://taginfo.openstreetmap.org/tags/waterway=wadi#map the uses in Europe for example are probably almost always seasonal. * sporadic waterflow is very difficult to determine for the mapper. This is especially true for northern Africa where climate got a lot drier in the last few thousand years and as a result there are many permanently dry valleys that still look like being formed by waterflow but that have not seen significant waterflow in the last hundred years. My suggestion would probably be to stop rendering waterway=wadi in a way implying waterflow, encourage mappers to use intermittent/seasonal where this is known and reserve waterway=wadi - despite the then misleading key - for valleys where waterflow is unknown. -- Christoph Hormann http://www.imagico.de/ ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
That’s all of San Diego - the storm drain system is so anemic - I’ve hydroplaned my car down the freeway (“Surfing interstate 5”), and forded a few “intermittent” rivers before I moved to Japan. here in Japan, torrential rain is really a non-issue most of the time - whereas a few cm of rain in Southern California means death on the roads and flooding underpasses. maybe it’s all the bald tires, oily roads, and people going 30-40km/h over what they should be driving. One wonders. ^_^ Javbw On Jan 16, 2015, at 9:27 AM, Eugene Alvin Villar sea...@gmail.com wrote: Given the current discussion, I wonder if roads that are usually flooded during heavy rainfall should be also be tagged as waterway=river/stream and intermittent=yes. ;-) On Fri, Jan 16, 2015 at 7:27 AM, John F. Eldredge j...@jfeldredge.com mailto:j...@jfeldredge.com wrote: I would recommend expanding the definition of intermittent streams to include not only streams that have a regular, seasonal water flow but also streams in desert areas that exist only when a rare storm comes along. The topography is the same, the tendency of water to run downhill is the same, only the frequency of rainfall is different. -- John F. Eldredge -- j...@jfeldredge.com mailto:j...@jfeldredge.com Darkness cannot drive out darkness; only light can do that. Hate cannot drive out hate; only love can do that. -- Martin Luther King, Jr. On January 15, 2015 3:13:38 AM Christoph Hormann chris_horm...@gmx.de mailto:chris_horm...@gmx.de wrote: On Thursday 15 January 2015, johnw wrote: A wadi is a place where flash floods occur. It is not an intermittent river - it isn’t really seasonally wet, and doesn’t provide any real expectation that water will be present (except deep underground) - because they are located in places where rain itself is unexpected for most of the year. Well - that would be a useful concept of a wadi but it has two problems: * current use of the tag is very different from that, you can see that quite well when you look at the taginfo map: https://taginfo.openstreetmap.org/tags/waterway=wadi#map https://taginfo.openstreetmap.org/tags/waterway=wadi#map the uses in Europe for example are probably almost always seasonal. * sporadic waterflow is very difficult to determine for the mapper. This is especially true for northern Africa where climate got a lot drier in the last few thousand years and as a result there are many permanently dry valleys that still look like being formed by waterflow but that have not seen significant waterflow in the last hundred years. My suggestion would probably be to stop rendering waterway=wadi in a way implying waterflow, encourage mappers to use intermittent/seasonal where this is known and reserve waterway=wadi - despite the then misleading key - for valleys where waterflow is unknown. -- Christoph Hormann http://www.imagico.de/ http://www.imagico.de/ ___ Tagging mailing list Tagging@openstreetmap.org mailto:Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org mailto:Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Thursday 15 January 2015, johnw wrote: A wadi is a place where flash floods occur. It is not an intermittent river - it isn’t really seasonally wet, and doesn’t provide any real expectation that water will be present (except deep underground) - because they are located in places where rain itself is unexpected for most of the year. Well - that would be a useful concept of a wadi but it has two problems: * current use of the tag is very different from that, you can see that quite well when you look at the taginfo map: https://taginfo.openstreetmap.org/tags/waterway=wadi#map the uses in Europe for example are probably almost always seasonal. * sporadic waterflow is very difficult to determine for the mapper. This is especially true for northern Africa where climate got a lot drier in the last few thousand years and as a result there are many permanently dry valleys that still look like being formed by waterflow but that have not seen significant waterflow in the last hundred years. My suggestion would probably be to stop rendering waterway=wadi in a way implying waterflow, encourage mappers to use intermittent/seasonal where this is known and reserve waterway=wadi - despite the then misleading key - for valleys where waterflow is unknown. -- Christoph Hormann http://www.imagico.de/ ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
Am 15.01.2015 um 05:27 schrieb John Willis jo...@mac.com: I'm really surprised you were shot down from using wadi when it is the most applicable tag for the item, sometimes the most applicable tag is not sufficiently well describing/ distinguishing a feature and it is better to introduce a new tag that fits 100% To me, the Term wadi is quite specific for certain waterways that occur in a certain region of the world. We can decide whether we'd want to use it anyway everywhere for similar (or partly similar) features or if we introduce other, dedicated tags on the same level of specificity for these features. Why not having a tag waterway=wash, or are those really the same than a wadi? cheers, Martin ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
It would be nice if the default rendering at www.openstreetmap.org would also recognize the intermittent tag. Implementing that I mentioned in top post is for default style - see https://github.com/gravitystorm/openstreetmap-carto/pull/1000 2015-01-14 18:00 GMT+01:00 Tod Fitch t...@fitchdesign.com: On Jan 14, 2015, at 8:28 AM, Wolfgang Zenker wrote: * Mateusz Konieczny matkoni...@gmail.com [150114 15:45]: waterway=wadi is used (18 180 times) and has some support (for example JOSM and default map style). During implementing rendering of intermittent=yes I discovered major problem with this tag - the same waterway=wadi may be used for completely dried up waterway, intermittent stream, intermittent major river and intermittent ditch. Therefore - it seems that using waterway=river/canal/stream/ditch/drain + intermittent=yes is clearly superior to using waterway=wadi. In my experience a wadi will go from completely dried up waterway or small stream to a raging river within a few seconds after some rainfall upstream, and back to its former self within a few hours. Depending on the location, these rainfall events might very well be a few years apart. When I tag an intermittent stream I usually have something more benign in mind, like a stream that only exists during the spring snow melt and is dry the rest of the year, but maybe that is only my interpretation of an intermittent stream. Wolfgang Your description of wadi matches many things locally called a wash in the U.S. desert southwest. Yet when I suggested that I tag those as wadi I was shot down. :) I've taken to tagging them as waterway=river/stream (depending on width) and intermittent=yes. And, yes, in these cases intermittent may mean that it only carries water for an hour or two every couple of years. The United States Geological Survey (USGS) topographic maps will show them as either a line of sand or an intermittent waterway depending, I think, on whim of the cartographer. A while back I submitted a change to the rendering for OsmAnd to recognize intermittent=yes as without that desert areas look way to wet. For the paper maps that I generate I've also created a Mapnik style that recognizes intermittent=yes and uses the USGS style intermittent rendering. It would be nice if the default rendering at www.openstreetmap.org would also recognize the intermittent tag. ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
I strongly disagree. A wadi is usually only an active river through very rare flash flood events, and almost never any other time. Entire biomes are defined by the presence of (and situated in) a wadi. In america, the words Arroyo and wash roughly translate into wadi, and because of the ambiguous nature of arroyo, the term wadi is used for a wash or arroyo when referring to a usually dry stream/riverbed that is dangerous in flash flood conditions. my experience with washes stems from the Southern California Desert, where most of the state park would basically be covered in blue, if washes were somehow labeled as rivers - some are 100m across. Whole road systems exist in the washes (and are reestablished purely by use after a flood), as the rest of the land is almost impassable. I have driven a couple thousand miles in a roughly 50x50 mile box over a hundred or so driving trips, and only on 3 occasions was water ever present, and at that time, the roads were completely impassable (a meter or so of water filled up the Carrizo wash 30m wide). Although several famous arroyos (like the LA River) are now basically man-made drainage ditches, mapping desert areas properly requires the wadi tag, as they are different from intermittent rivers - in the fact that water in the “bed is *never expected* - even seasonally - and if present it is a dangerous flash flood. There is never an in-between state of what you would call “a river” for longer than a day. - as it disappears almost immediately as soon as the flood is over (except in the most exceptional of weather conditions). - kind of like an avalanche is only an avalanche while it is moving, or an earthquake is is an event. A wadi is a place where flash floods occur. It is not an intermittent river - it isn’t really seasonally wet, and doesn’t provide any real expectation that water will be present (except deep underground) - because they are located in places where rain itself is unexpected for most of the year. A wadi has an expectation of always being dry, except for the rare and unpredictable flash flood. t and in that case, you should assume it is a dangerous, and impassable place. I think, espcially since it is defined and used so heavily, and has a different connotation than a river - even a intermittent one, it should be kept. a wash near Borrego springs, CA (ironwood wash, Tubb canyon). it drains to a sink in the middle of the desert (the white spot in the upper right) https://www.flickr.com/photos/javbw/11091366554/in/set-72157638113734675 https://www.flickr.com/photos/javbw/11091366554/in/set-72157638113734675 https://goo.gl/maps/fpSxE Javbw On Jan 14, 2015, at 11:45 PM, Mateusz Konieczny matkoni...@gmail.com wrote: waterway=wadi is used (18 180 times) and has some support (for example JOSM and default map style). During implementing rendering of intermittent=yes I discovered major problem with this tag - the same waterway=wadi may be used for completely dried up waterway, intermittent stream, intermittent major river and intermittent ditch. Therefore - it seems that using waterway=river/canal/stream/ditch/drain + intermittent=yes is clearly superior to using waterway=wadi. ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Jan 15, 2015, at 2:00 AM, Tod Fitch t...@fitchdesign.com wrote: On Jan 14, 2015, at 8:28 AM, Wolfgang Zenker wrote: In my experience a wadi will go from completely dried up waterway or small stream to a raging river within a few seconds after some rainfall upstream, and back to its former self within a few hours. Depending on the location, these rainfall events might very well be a few years apart. When I tag an intermittent stream I usually have something more benign in mind, like a stream that only exists during the spring snow melt and is dry the rest of the year, but maybe that is only my interpretation of an intermittent stream. Wolfgang +1. This is exactly how I see the difference - especially since when there is water, it is usually a dangerous, unexpected thing. Your description of wadi matches many things locally called a wash in the U.S. desert southwest. Yet when I suggested that I tag those as wadi I was shot down. I added wash as a description to wadi on the osm wiki last year when I was thinking of mapping the San Diego county deserts (as even in Wikipedia it is a round Robbin of links between arroyo and wadi). I'll have to look at the edit history to see if it got pulled off. This was before I understood that adding a description to the wiki was potentially controversial: I thought I was adding something glaringly obvious and helpfully updating the wiki at the same time I'm really surprised you were shot down from using wadi when it is the most applicable tag for the item, and I'm surprised that there is discussion of axing a well used tag, which defines a known and named geographic feature, for the sake of jamming it under rivers. I always imagine we will be discussion of adding more and more specialized tags, as micro mappers keep labeling smaller an smaller stuff - or. Like the wadi tag - expand our definitions of basic tags to better define what is around us. I wonder if the people who shot you down have even ever seen a wash, let alone are familiar with them. I know it's a no true Scotsman fallacy, but that's what it feels like. Javbw ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
[Tagging] waterway=wadi problem
waterway=wadi is used (18 180 times) and has some support (for example JOSM and default map style). During implementing rendering of intermittent=yes I discovered major problem with this tag - the same waterway=wadi may be used for completely dried up waterway, intermittent stream, intermittent major river and intermittent ditch. Therefore - it seems that using waterway=river/canal/stream/ditch/drain + intermittent=yes is clearly superior to using waterway=wadi. ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
Can you consider making proposal for waterway=wadi on wiki? Or maybe other tag, as waterway=wadi is frequently used to mark intermittent streams? Currently http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dwadi is not mentioning anything like that. Note, I am not disputing usefulness of term wadi. I am disputing usefulness of waterway=wadi tag due to lack on any agreed definition and description on OSM wiki. 2015-01-15 3:41 GMT+01:00 johnw jo...@mac.com: I strongly disagree. A wadi is usually only an active river through very rare flash flood events, and almost never any other time. Entire biomes are defined by the presence of (and situated in) a wadi. In america, the words Arroyo and wash roughly translate into wadi, and because of the ambiguous nature of arroyo, the term wadi is used for a wash or arroyo when referring to a usually dry stream/riverbed that is dangerous in flash flood conditions. my experience with washes stems from the Southern California Desert, where most of the state park would basically be covered in blue, if washes were somehow labeled as rivers - some are 100m across. Whole road systems exist in the washes (and are reestablished purely by use after a flood), as the rest of the land is almost impassable. I have driven a couple thousand miles in a roughly 50x50 mile box over a hundred or so driving trips, and only on 3 occasions was water ever present, and at that time, the roads were completely impassable (a meter or so of water filled up the Carrizo wash 30m wide). Although several famous arroyos (like the LA River) are now basically man-made drainage ditches, mapping desert areas properly requires the wadi tag, as they are different from intermittent rivers - in the fact that water in the “bed is *never expected* - even seasonally - and if present it is a dangerous flash flood. There is never an in-between state of what you would call “a river” for longer than a day. - as it disappears almost immediately as soon as the flood is over (except in the most exceptional of weather conditions). - kind of like an avalanche is only an avalanche while it is moving, or an earthquake is is an event. A wadi is a place where flash floods occur. It is not an intermittent river - it isn’t really seasonally wet, and doesn’t provide any real expectation that water will be present (except deep underground) - because they are located in places where rain itself is unexpected for most of the year. A wadi has an expectation of always being dry, except for the rare and unpredictable flash flood. t and in that case, you should assume it is a dangerous, and impassable place. I think, espcially since it is defined and used so heavily, and has a different connotation than a river - even a intermittent one, it should be kept. a wash near Borrego springs, CA (ironwood wash, Tubb canyon). it drains to a sink in the middle of the desert (the white spot in the upper right) https://www.flickr.com/photos/javbw/11091366554/in/set-72157638113734675 https://goo.gl/maps/fpSxE Javbw On Jan 14, 2015, at 11:45 PM, Mateusz Konieczny matkoni...@gmail.com wrote: waterway=wadi is used (18 180 times) and has some support (for example JOSM and default map style). During implementing rendering of intermittent=yes I discovered major problem with this tag - the same waterway=wadi may be used for completely dried up waterway, intermittent stream, intermittent major river and intermittent ditch. Therefore - it seems that using waterway=river/canal/stream/ditch/drain + intermittent=yes is clearly superior to using waterway=wadi. ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
I’ll make one up in the next few hours. I want to research wadis in other countries to make sure I’m not assuming my regional experience is misrepresenting the whole. Javbw On Jan 15, 2015, at 3:24 PM, Mateusz Konieczny matkoni...@gmail.com wrote: Can you consider making proposal for waterway=wadi on wiki? Or maybe other tag, as waterway=wadi is frequently used to mark intermittent streams? Currently http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dwadi http://wiki.openstreetmap.org/wiki/Tag:waterway%3Dwadi is not mentioning anything like that. Note, I am not disputing usefulness of term wadi. I am disputing usefulness of waterway=wadi tag due to lack on any agreed definition and description on OSM wiki. 2015-01-15 3:41 GMT+01:00 johnw jo...@mac.com mailto:jo...@mac.com: I strongly disagree. A wadi is usually only an active river through very rare flash flood events, and almost never any other time. Entire biomes are defined by the presence of (and situated in) a wadi. In america, the words Arroyo and wash roughly translate into wadi, and because of the ambiguous nature of arroyo, the term wadi is used for a wash or arroyo when referring to a usually dry stream/riverbed that is dangerous in flash flood conditions. my experience with washes stems from the Southern California Desert, where most of the state park would basically be covered in blue, if washes were somehow labeled as rivers - some are 100m across. Whole road systems exist in the washes (and are reestablished purely by use after a flood), as the rest of the land is almost impassable. I have driven a couple thousand miles in a roughly 50x50 mile box over a hundred or so driving trips, and only on 3 occasions was water ever present, and at that time, the roads were completely impassable (a meter or so of water filled up the Carrizo wash 30m wide). Although several famous arroyos (like the LA River) are now basically man-made drainage ditches, mapping desert areas properly requires the wadi tag, as they are different from intermittent rivers - in the fact that water in the “bed is *never expected* - even seasonally - and if present it is a dangerous flash flood. There is never an in-between state of what you would call “a river” for longer than a day. - as it disappears almost immediately as soon as the flood is over (except in the most exceptional of weather conditions). - kind of like an avalanche is only an avalanche while it is moving, or an earthquake is is an event. A wadi is a place where flash floods occur. It is not an intermittent river - it isn’t really seasonally wet, and doesn’t provide any real expectation that water will be present (except deep underground) - because they are located in places where rain itself is unexpected for most of the year. A wadi has an expectation of always being dry, except for the rare and unpredictable flash flood. t and in that case, you should assume it is a dangerous, and impassable place. I think, espcially since it is defined and used so heavily, and has a different connotation than a river - even a intermittent one, it should be kept. a wash near Borrego springs, CA (ironwood wash, Tubb canyon). it drains to a sink in the middle of the desert (the white spot in the upper right) https://www.flickr.com/photos/javbw/11091366554/in/set-72157638113734675 https://www.flickr.com/photos/javbw/11091366554/in/set-72157638113734675 https://goo.gl/maps/fpSxE https://goo.gl/maps/fpSxE Javbw On Jan 14, 2015, at 11:45 PM, Mateusz Konieczny matkoni...@gmail.com mailto:matkoni...@gmail.com wrote: waterway=wadi is used (18 180 times) and has some support (for example JOSM and default map style). During implementing rendering of intermittent=yes I discovered major problem with this tag - the same waterway=wadi may be used for completely dried up waterway, intermittent stream, intermittent major river and intermittent ditch. Therefore - it seems that using waterway=river/canal/stream/ditch/drain + intermittent=yes is clearly superior to using waterway=wadi. ___ Tagging mailing list Tagging@openstreetmap.org mailto:Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org mailto:Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
* Mateusz Konieczny matkoni...@gmail.com [150114 15:45]: waterway=wadi is used (18 180 times) and has some support (for example JOSM and default map style). During implementing rendering of intermittent=yes I discovered major problem with this tag - the same waterway=wadi may be used for completely dried up waterway, intermittent stream, intermittent major river and intermittent ditch. Therefore - it seems that using waterway=river/canal/stream/ditch/drain + intermittent=yes is clearly superior to using waterway=wadi. In my experience a wadi will go from completely dried up waterway or small stream to a raging river within a few seconds after some rainfall upstream, and back to its former self within a few hours. Depending on the location, these rainfall events might very well be a few years apart. When I tag an intermittent stream I usually have something more benign in mind, like a stream that only exists during the spring snow melt and is dry the rest of the year, but maybe that is only my interpretation of an intermittent stream. Wolfgang ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Jan 14, 2015, at 8:28 AM, Wolfgang Zenker wrote: * Mateusz Konieczny matkoni...@gmail.com [150114 15:45]: waterway=wadi is used (18 180 times) and has some support (for example JOSM and default map style). During implementing rendering of intermittent=yes I discovered major problem with this tag - the same waterway=wadi may be used for completely dried up waterway, intermittent stream, intermittent major river and intermittent ditch. Therefore - it seems that using waterway=river/canal/stream/ditch/drain + intermittent=yes is clearly superior to using waterway=wadi. In my experience a wadi will go from completely dried up waterway or small stream to a raging river within a few seconds after some rainfall upstream, and back to its former self within a few hours. Depending on the location, these rainfall events might very well be a few years apart. When I tag an intermittent stream I usually have something more benign in mind, like a stream that only exists during the spring snow melt and is dry the rest of the year, but maybe that is only my interpretation of an intermittent stream. Wolfgang Your description of wadi matches many things locally called a wash in the U.S. desert southwest. Yet when I suggested that I tag those as wadi I was shot down. :) I've taken to tagging them as waterway=river/stream (depending on width) and intermittent=yes. And, yes, in these cases intermittent may mean that it only carries water for an hour or two every couple of years. The United States Geological Survey (USGS) topographic maps will show them as either a line of sand or an intermittent waterway depending, I think, on whim of the cartographer. A while back I submitted a change to the rendering for OsmAnd to recognize intermittent=yes as without that desert areas look way to wet. For the paper maps that I generate I've also created a Mapnik style that recognizes intermittent=yes and uses the USGS style intermittent rendering. It would be nice if the default rendering at www.openstreetmap.org would also recognize the intermittent tag. ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
Re: [Tagging] waterway=wadi problem
On Wednesday 14 January 2015, Tod Fitch wrote: [...] The United States Geological Survey (USGS) topographic maps will show them as either a line of sand or an intermittent waterway depending, I think, on whim of the cartographer. USGS data distinguishes between intermittent, perennial and ephemeral: http://nhd.usgs.gov/userGuide/Robohelpfiles/NHD_User_Guide/Feature_Catalog/Hydrography_Dataset/NHDFlowline/StreamRiver.htm which well translates into OSM tags: intermittent: waterway=*, intermittent=yes, seasonal=yes perennial: waterway=* ephemeral: waterway=*, intermittent=yes, seasonal=no although i don't think past imports of NHD data have made this distinction. waterway=wadi can mean either intermittent or ephemeral or permanently dry, see also https://wiki.openstreetmap.org/wiki/Talk:Tag:waterway%3Dwadi -- Christoph Hormann http://www.imagico.de/ ___ Tagging mailing list Tagging@openstreetmap.org https://lists.openstreetmap.org/listinfo/tagging
