[Tagging] Tagging sewage treatment basins

[Minh Nguyen]

Vào lúc 09:42 2020-12-18, Martin Koppenhoefer đã viết:
> Am Fr., 18. Dez. 2020 um 12:32 Uhr schrieb Paul Allen 
> <pla16021 at gmail.com 
> <mailto:pla16021 at gmail.com>>:
> 
>     I'm not entirely happy with natural=water being applied to either sewage
>     treatment or slurry.  Neither are natural and neither store water.
> 
> 
> 
> neither am I, not for the question of how "natural" they are (ship has 
> sailed) but because I would not consider "slurry" to be "water", 
> although they contain mostly water (looking at the parts) - 10% sulfuric 
> acid is also mostly water. Milk is also mostly water, as is beer.

I'm glad I'm not alone in stubbornly avoiding the troll-tagging of 
tailing ponds and pig lagoons as natural=water. I'm fine with putting 
most reservoirs under natural=water, but this tag doesn't have to hold a 
monopoly on bodies of liquid. After all, clorinated pool water is mostly 
water, but we use leisure=swimming_pool as has been mentioned. A marsh 
is mostly covered by naturally collecting water, but there's 
natural=wetland and a whole wetland=* tagging scheme for that.

Most paper maps I've come across have treated bodies of water as 
distinct from bodies of other liquids, if they show the latter at all. 
For example, the USGS topographic maps cited earlier in this thread make 
no distinction between natural lakes and dammed reservoirs, but tailing 
ponds have completely different symbology. [1] If a renderer were 
unprepared to give special treatment to tailing ponds, I personally 
think it would be better for the renderer to omit them than to render 
them as bodies of water. That might require an altogether different 
primary tag like man_made=reservoir, since it's so common to render 
landuse=reservoir just like natural=water.

landuse=reservoir is an unintuitive tag for water-filled reservoirs, 
anyways. The pedant in me wants to double-map a reservoir as two areas: 
a landuse=reservoir area for the land underneath and a coincident, 
connected natural=water area for the H2O above it. But people complain 
about connecting landuse areas to other features, so I'll have to wait 
until April Fool's Day. ;-)

[1] 
https://pubs.usgs.gov/gip/TopographicMapSymbols/topomapsymbols.pdf#page=4

-- 
minh at nguyen.cincinnati.oh.us