With the recent typhoon in Japan, I was able to see the giant river flood
control systems used for the first time (since I moved here in 2011). they are
the size of cities, covering many sq KM.
There are some photos here, showing a cycling trip I took downriver to see how
it works.
https://im
On Thu, 24 Oct 2019 at 10:56, John Willis via Tagging <
tagging@openstreetmap.org> wrote:
Inside, there are three “retarding basins” (numbered 1, 2 & 3), with #1
> having with a large traditional reservoir, parks, golf course, and sports
> grounds inside.
>
There is more to the system than that.
I am aware of the underground basins that are dedicated to the task, but I am
wondering how to map above-ground basins that are used as regular land 360+
days of the year - something you don't have to deal with when mapping the
underground tanks.
~
The rest is not important, but read on
I think describing these as "flood prone" in some way is a good idea.
I imagine you've already mapped the individual features: the levees
(man_made=dyke), the individual basins and so on. I wouldn't want to
map the whole area as water + intermittent=yes because the water is
only rarely present.
P
> On Oct 24, 2019, at 10:22 PM, Joseph Eisenberg
> wrote:
>
> rendering for areas that are "subject to inundation".
That is a good idea.
I think if you have a large area(unrelated to tides) that sometimes floods
during extreme weather, mapping it as an area would be a good idea.
I wonder
In a *much* smaller way, we've got a similar area just near us, where an
area has been built to be filled with flood water after very heavy rain. I
think it's probably only filled 3-4 times in ~15 years since it was put in.
Some photo's, wet & dry!
https://ibb.co/SdVF7kt
https://ibb.co/4N3mWzQ
h
On 25/10/19 00:20, Joseph Eisenberg wrote:
I think describing these as "flood prone" in some way is a good idea.
I think it would be better to use "flood_mitigation" as that implies deliberate
design rather than natural event.
I imagine you've already mapped the individual features: the l
I think that should be basin=detention or perhaps basin=infiltration?
A retention basin is filled with water most of the time.
basin=infiltration — An infiltration basin catches storm water and
allows it to seep into an aquifer.
basin=detention — A detention basin catches storm water and allows it
I see what you mean. Perhaps the key can help show this:
man_made=* for a built environment designed to hold flood waters
natural=* for a semi-natural or natural area that occasionally floods
(like some basins the the Australian outback, which form lakes only
once every 10 or 100 years?)
The val
> On Oct 25, 2019, at 10:53 AM, Joseph Eisenberg
> wrote:
>
> The value should have something that suggests that it will be flooded.
> I would think of "flood_mitigation" as something like a levee or dyke
> which prevents flooding, rather than an area that is supposem to be
> flooded.
>
> So..
Le 25.10.19 à 20:29, John Willis via Tagging a écrit :
>
>> On Oct 25, 2019, at 10:53 AM, Joseph Eisenberg
>> wrote:
>>
>> The value should have something that suggests that it will be flooded.
>> I would think of "flood_mitigation" as something like a levee or dyke
>> which prevents flooding, r
> On Oct 26, 2019, at 6:01 AM, marc marc wrote:
>>
>> Man_made=flood_mitigation_basin sounds good.
>
> that look like 2 infos into one key :s
>
> man_made=basin usage=flood_mitigation ?
Yes, my bad. I think that is a good solution for the basin.
One big question. Something has been botherin
the government released photos of the water control features I’ve mentioned
being filled by the recent typhoon. The “flooding” pictured is by design,
controlled by short inner and large, tall outer levees.
This should give people a better idea of the scale of the water features I am
talking ab
On Thu, 7 Nov 2019 at 09:50, John Willis via Tagging <
tagging@openstreetmap.org> wrote:
That's amazing, thanks, John
~The recent typhoon that completely filled the basins & rivers to become
> one giant lake (as designed) controlled by the outer levees:
>
> http://www.ktr.mlit.go.jp/ktr_content/c
14 matches
Mail list logo