Re: [Tagging] How to tag flood prone points and areas?

[Mateusz Konieczny]

2 Sep 2019, 23:20 by graemefi...@gmail.com:

>
>
> On Mon, 2 Sep 2019 at 16:38, Mateusz Konieczny <> matkoni...@tutanota.com 
> > > wrote:
>
>> This kind of data is not
>> verifiable and not surveyable by an
>> OSM mapper.
>>
>
> The place I'm thinking of, there's a yellow line painted on the wall of the 
> car park, approximately 1.2m high, labelled "1 in 100 year flood level".
>
> To me, that's verifiable & surveyable.
>
In this case - it makes sense to map it.

I reacted this way without specifying 
"Except in case of explicit signs"
as I have never seen something like that
and I am aware about multiple
(contradictory) studies of food probability
for my region.___
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Re: [Tagging] How to tag flood prone points and areas?

[Graeme Fitzpatrick]

On Mon, 2 Sep 2019 at 16:38, Mateusz Konieczny 
wrote:

> This kind of data is not
> verifiable and not surveyable by an
> OSM mapper.
>

The place I'm thinking of, there's a yellow line painted on the wall of the
car park, approximately 1.2m high, labelled "1 in 100 year flood level".

To me, that's verifiable & surveyable.

Thanks

Graeme
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Re: [Tagging] How to tag flood prone points and areas?

[Mateusz Konieczny]

2 Sep 2019, 03:21 by graemefi...@gmail.com:

>
>
> On Sun, 1 Sep 2019 at 21:57, Paul Allen <> pla16...@gmail.com 
> > > wrote:
>
>>
>> I'm fairly happy with flood_probability.  There's something nagging at the 
>> back of my
>> mind saying I ought to be unhappy with flood_probability, but it's not 
>> telling me why.
>>
>
> How about something like:
> flood_potential=100y / 1% + depth=1.2
>
This kind of data is not
verifiable and not surveyable by an
OSM mapper.

It is impossible to improve, verify
or maintain this.
There is no point in dumping it into OSM,
it should stay as a separate dataset.___
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Re: [Tagging] How to tag flood prone points and areas?

[Graeme Fitzpatrick]

On Sun, 1 Sep 2019 at 21:57, Paul Allen  wrote:

>
> I'm fairly happy with flood_probability.  There's something nagging at the
> back of my
> mind saying I ought to be unhappy with flood_probability, but it's not
> telling me why.
>

How about something like:
flood_potential=100y / 1% + depth=1.2

Thanks

Graeme
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Re: [Tagging] How to tag flood prone points and areas?

[Warin]

On 1/9/19 10:31 pm, François Lacombe wrote:

Hi all,

flood_prone=yes doesn't sound to be good semantics.



Think those are the words used on signs, so for English areas they make 
sense..


Should we rewrite it as floodable=* with 3 or four big level of 
probability (or causes, or whatever) instead?



I don't think floodable is right .. to me it says that a feature has a 
tolerance for flooding, once the flood is past the feature is ok. Where 
as flood_prone says the feature may be under water (flooded) from time 
to time. After the flood flood_prone says nothing about the recovery of 
the feature from the flooding.




Many people raised concerns about yes/no tags and the key name seem to 
contain two distinct information (floodable + probability) while the 
value meaning could be improved.


Furthermore, such work can be useful for many hazard description.
This proposal is interesting : 
https://wiki.openstreetmap.org/wiki/Proposed_features/hazard


Floods can also occur on river banks surroundings when hydropower is 
in operation upstream

https://lists.openstreetmap.org/pipermail/tagging/2018-July/037973.html
Here is what is often displayed : https://imgur.com/a/TLhZcgE

All the best

François

Le dim. 1 sept. 2019 à 14:07, Joseph Eisenberg 
mailto:joseph.eisenb...@gmail.com>> a écrit :


For `flood_probability` to be useful and verifiable in some way, there
should be a link to the source in the changeset, or perhaps also
source: flood_probability= on the object.

Such statistical features like "1% risk of flood per year" can't
really be verified by individual mappers, since they are based on
calculations of the floodplain geometry and historical observations of
floods over many decades. So it's probably more useful to have these
mapped in official sources which are kept up-to-date, rather than
importing the data from the external source into OSM, and then having
to maintain it in our database.

I agree that if there is a sign that says "this area prone to
flooding", then "flood_prone=yes" is verifiable and helpful to add,
since that's representing a feature that can be checked when the area
is next survey.

On 9/1/19, Paul Allen mailto:pla16...@gmail.com>> wrote:
> On Sun, 1 Sep 2019 at 05:24, Warin <61sundow...@gmail.com
> wrote:
>
> You could add flood_prone=yes to the car park tag but that will
show the
>> whole car park as affected, whereas it's only the bit down this
end that
>> has a problem. Would drawing a separate area & marking that as
>> flood_prone=yes work?
>>
>
> Better than nothing.  If you feel adventurous, you could try
mapping it as
> two, non-overlapping,
> constituent areas of a multipolygon and see what happens.
>
>> I asked this question some time ago. I was told it was not
verifiable and
>> therefore not for OSM.
>>
>
> My opinion is that if there is signage/road markings it's
verifiable and
> mappable.  When we
> map the speed limit of a road from signs the only actual, verifiable
> information we have is
> the presence of the sign, but we assume the sign is true and
infer the
> speed limit of the
> road from it.  Same thing here: sign says it's prone to floods
so we infer
> the place is prone to
> floods.
>
> Where I differ from some is that I'd consider official documents
also
> providing verifiability
> provided their copyright permits it.
>
> However there is the question of frequency, once in 10 year
event, once in
>> 100 etc. So I would add a sub tag or value about frequency of
the event..
>> The key frequency is already in use. Period has some use too,
though the
>> use looks to be years.. no wiki to say what it is?
>>
>
> Period is the multiplicative inverse of frequency: normalize the
units,
> multiply them together
> and the result should be 1.  Neither is appropriate in this case.  A
> once-in-100-year event
> does not occur at 100 year intervals, it has a probability of  1% of
> occurring (technically,
> being equalled or exceeded) in any given year.
> https://en.wikipedia.org/wiki/100-year_flood
> So we should be tagging a probability.  Technically, exceedance
probability
> for floods.
>
> Taginfo shows floodplain_probability used 77 times.  Is that
sensible?
> It's a floodplain or it isn't.
> Also flood_probability 4 times (better) and hazard:probability
once.  The
> flood_probability value
> in taginfo is "100y" rather than 1%.  People who used
> floodplain_probability divide into those
> who expressed a large number like 100 (probably meaning years)
and those
> who expressed
> a small number like 1 or 0.5 (probably a percentage). The only
value for
> hazard:probability

Re: [Tagging] How to tag flood prone points and areas?

[Martin Koppenhoefer]

sent from a phone

> On 1. Sep 2019, at 14:05, Joseph Eisenberg  wrote:
> 
> since they are based on
> calculations of the floodplain geometry and historical observations of
> floods over many decades


indeed, and with a changing ecosystem (warming) statistical predictions will 
also be less reliable anyway.

If we want to tag “flood prone” as a building (or other object) property, it 
could make sense to state how many (centi)meters above (regular) high water it 
would cause (immediate/short term) problems.

Cheers Martin 
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Re: [Tagging] How to tag flood prone points and areas?

[François Lacombe]

Hi all,

flood_prone=yes doesn't sound to be good semantics.
Should we rewrite it as floodable=* with 3 or four big level of probability
(or causes, or whatever) instead?

Many people raised concerns about yes/no tags and the key name seem to
contain two distinct information (floodable + probability) while the value
meaning could be improved.

Furthermore, such work can be useful for many hazard description.
This proposal is interesting :
https://wiki.openstreetmap.org/wiki/Proposed_features/hazard

Floods can also occur on river banks surroundings when hydropower is in
operation upstream
https://lists.openstreetmap.org/pipermail/tagging/2018-July/037973.html
Here is what is often displayed : https://imgur.com/a/TLhZcgE

All the best

François

Le dim. 1 sept. 2019 à 14:07, Joseph Eisenberg 
a écrit :

> For `flood_probability` to be useful and verifiable in some way, there
> should be a link to the source in the changeset, or perhaps also
> source: flood_probability= on the object.
>
> Such statistical features like "1% risk of flood per year" can't
> really be verified by individual mappers, since they are based on
> calculations of the floodplain geometry and historical observations of
> floods over many decades. So it's probably more useful to have these
> mapped in official sources which are kept up-to-date, rather than
> importing the data from the external source into OSM, and then having
> to maintain it in our database.
>
> I agree that if there is a sign that says "this area prone to
> flooding", then "flood_prone=yes" is verifiable and helpful to add,
> since that's representing a feature that can be checked when the area
> is next survey.
>
> On 9/1/19, Paul Allen  wrote:
> > On Sun, 1 Sep 2019 at 05:24, Warin <61sundow...@gmail.com> wrote:
> >
> > You could add flood_prone=yes to the car park tag but that will show the
> >> whole car park as affected, whereas it's only the bit down this end that
> >> has a problem. Would drawing a separate area & marking that as
> >> flood_prone=yes work?
> >>
> >
> > Better than nothing.  If you feel adventurous, you could try mapping it
> as
> > two, non-overlapping,
> > constituent areas of a multipolygon and see what happens.
> >
> >> I asked this question some time ago. I was told it was not verifiable
> and
> >> therefore not for OSM.
> >>
> >
> > My opinion is that if there is signage/road markings it's verifiable and
> > mappable.  When we
> > map the speed limit of a road from signs the only actual, verifiable
> > information we have is
> > the presence of the sign, but we assume the sign is true and infer the
> > speed limit of the
> > road from it.  Same thing here: sign says it's prone to floods so we
> infer
> > the place is prone to
> > floods.
> >
> > Where I differ from some is that I'd consider official documents also
> > providing verifiability
> > provided their copyright permits it.
> >
> > However there is the question of frequency, once in 10 year event, once
> in
> >> 100 etc. So I would add a sub tag or value about frequency of the
> event..
> >> The key frequency is already in use. Period has some use too, though the
> >> use looks to be years.. no wiki to say what it is?
> >>
> >
> > Period is the multiplicative inverse of frequency: normalize the units,
> > multiply them together
> > and the result should be 1.  Neither is appropriate in this case.  A
> > once-in-100-year event
> > does not occur at 100 year intervals, it has a probability of  1% of
> > occurring (technically,
> > being equalled or exceeded) in any given year.
> > https://en.wikipedia.org/wiki/100-year_flood
> > So we should be tagging a probability.  Technically, exceedance
> probability
> > for floods.
> >
> > Taginfo shows floodplain_probability used 77 times.  Is that sensible?
> > It's a floodplain or it isn't.
> > Also flood_probability 4 times (better) and hazard:probability once.  The
> > flood_probability value
> > in taginfo is "100y" rather than 1%.  People who used
> > floodplain_probability divide into those
> > who expressed a large number like 100 (probably meaning years) and those
> > who expressed
> > a small number like 1 or 0.5 (probably a percentage).  The only value for
> > hazard:probability
> > is "low" (which I consider to be effectively meaningless).
> >
> > I dislike floodplain_probability because it IS a floodplain with a
> > probability of being
> > flooded, not a probability of an area being classified as a floodplain.
> > Also because
> > it's been given both in terms of years and percentages (except it's
> > impossible to be sure
> > because nobody has given units, so maybe the 100 means it's 100% likely
> to
> > flood and
> > the 0.5 means it is likely to flood every six months).  It's a mess.
> >
> > I'm fairly happy with flood_probability.  There's something nagging at
> the
> > back of my
> > mind saying I ought to be unhappy with flood_probability, but it's not
> > telling me why.
> >
> > I like hazard:probability, especially if 

Re: [Tagging] How to tag flood prone points and areas?

[Joseph Eisenberg]

For `flood_probability` to be useful and verifiable in some way, there
should be a link to the source in the changeset, or perhaps also
source: flood_probability= on the object.

Such statistical features like "1% risk of flood per year" can't
really be verified by individual mappers, since they are based on
calculations of the floodplain geometry and historical observations of
floods over many decades. So it's probably more useful to have these
mapped in official sources which are kept up-to-date, rather than
importing the data from the external source into OSM, and then having
to maintain it in our database.

I agree that if there is a sign that says "this area prone to
flooding", then "flood_prone=yes" is verifiable and helpful to add,
since that's representing a feature that can be checked when the area
is next survey.

On 9/1/19, Paul Allen  wrote:
> On Sun, 1 Sep 2019 at 05:24, Warin <61sundow...@gmail.com> wrote:
>
> You could add flood_prone=yes to the car park tag but that will show the
>> whole car park as affected, whereas it's only the bit down this end that
>> has a problem. Would drawing a separate area & marking that as
>> flood_prone=yes work?
>>
>
> Better than nothing.  If you feel adventurous, you could try mapping it as
> two, non-overlapping,
> constituent areas of a multipolygon and see what happens.
>
>> I asked this question some time ago. I was told it was not verifiable and
>> therefore not for OSM.
>>
>
> My opinion is that if there is signage/road markings it's verifiable and
> mappable.  When we
> map the speed limit of a road from signs the only actual, verifiable
> information we have is
> the presence of the sign, but we assume the sign is true and infer the
> speed limit of the
> road from it.  Same thing here: sign says it's prone to floods so we infer
> the place is prone to
> floods.
>
> Where I differ from some is that I'd consider official documents also
> providing verifiability
> provided their copyright permits it.
>
> However there is the question of frequency, once in 10 year event, once in
>> 100 etc. So I would add a sub tag or value about frequency of the event..
>> The key frequency is already in use. Period has some use too, though the
>> use looks to be years.. no wiki to say what it is?
>>
>
> Period is the multiplicative inverse of frequency: normalize the units,
> multiply them together
> and the result should be 1.  Neither is appropriate in this case.  A
> once-in-100-year event
> does not occur at 100 year intervals, it has a probability of  1% of
> occurring (technically,
> being equalled or exceeded) in any given year.
> https://en.wikipedia.org/wiki/100-year_flood
> So we should be tagging a probability.  Technically, exceedance probability
> for floods.
>
> Taginfo shows floodplain_probability used 77 times.  Is that sensible?
> It's a floodplain or it isn't.
> Also flood_probability 4 times (better) and hazard:probability once.  The
> flood_probability value
> in taginfo is "100y" rather than 1%.  People who used
> floodplain_probability divide into those
> who expressed a large number like 100 (probably meaning years) and those
> who expressed
> a small number like 1 or 0.5 (probably a percentage).  The only value for
> hazard:probability
> is "low" (which I consider to be effectively meaningless).
>
> I dislike floodplain_probability because it IS a floodplain with a
> probability of being
> flooded, not a probability of an area being classified as a floodplain.
> Also because
> it's been given both in terms of years and percentages (except it's
> impossible to be sure
> because nobody has given units, so maybe the 100 means it's 100% likely to
> flood and
> the 0.5 means it is likely to flood every six months).  It's a mess.
>
> I'm fairly happy with flood_probability.  There's something nagging at the
> back of my
> mind saying I ought to be unhappy with flood_probability, but it's not
> telling me why.
>
> I like hazard:probability, especially if we document that it should be
> tagged as a
> percentage (and ignore or fix the sole value of "low").  Only problem with
> it is that
> hazard=* is a proposal from 2007 that is supposedly still active, so we'd
> have
> to do something about hazard=*.  Then again there is hazard_prone=* and
> hazard_type=* which seem to have appeared in the wiki without a proposal
> and have a few thousand uses.
>
> --
> Paul
>

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Re: [Tagging] How to tag flood prone points and areas?

[Paul Allen]

On Sun, 1 Sep 2019 at 05:24, Warin <61sundow...@gmail.com> wrote:

You could add flood_prone=yes to the car park tag but that will show the
> whole car park as affected, whereas it's only the bit down this end that
> has a problem. Would drawing a separate area & marking that as
> flood_prone=yes work?
>

Better than nothing.  If you feel adventurous, you could try mapping it as
two, non-overlapping,
constituent areas of a multipolygon and see what happens.

> I asked this question some time ago. I was told it was not verifiable and
> therefore not for OSM.
>

My opinion is that if there is signage/road markings it's verifiable and
mappable.  When we
map the speed limit of a road from signs the only actual, verifiable
information we have is
the presence of the sign, but we assume the sign is true and infer the
speed limit of the
road from it.  Same thing here: sign says it's prone to floods so we infer
the place is prone to
floods.

Where I differ from some is that I'd consider official documents also
providing verifiability
provided their copyright permits it.

However there is the question of frequency, once in 10 year event, once in
> 100 etc. So I would add a sub tag or value about frequency of the event..
> The key frequency is already in use. Period has some use too, though the
> use looks to be years.. no wiki to say what it is?
>

Period is the multiplicative inverse of frequency: normalize the units,
multiply them together
and the result should be 1.  Neither is appropriate in this case.  A
once-in-100-year event
does not occur at 100 year intervals, it has a probability of  1% of
occurring (technically,
being equalled or exceeded) in any given year.
https://en.wikipedia.org/wiki/100-year_flood
So we should be tagging a probability.  Technically, exceedance probability
for floods.

Taginfo shows floodplain_probability used 77 times.  Is that sensible?
It's a floodplain or it isn't.
Also flood_probability 4 times (better) and hazard:probability once.  The
flood_probability value
in taginfo is "100y" rather than 1%.  People who used
floodplain_probability divide into those
who expressed a large number like 100 (probably meaning years) and those
who expressed
a small number like 1 or 0.5 (probably a percentage).  The only value for
hazard:probability
is "low" (which I consider to be effectively meaningless).

I dislike floodplain_probability because it IS a floodplain with a
probability of being
flooded, not a probability of an area being classified as a floodplain.
Also because
it's been given both in terms of years and percentages (except it's
impossible to be sure
because nobody has given units, so maybe the 100 means it's 100% likely to
flood and
the 0.5 means it is likely to flood every six months).  It's a mess.

I'm fairly happy with flood_probability.  There's something nagging at the
back of my
mind saying I ought to be unhappy with flood_probability, but it's not
telling me why.

I like hazard:probability, especially if we document that it should be
tagged as a
percentage (and ignore or fix the sole value of "low").  Only problem with
it is that
hazard=* is a proposal from 2007 that is supposedly still active, so we'd
have
to do something about hazard=*.  Then again there is hazard_prone=* and
hazard_type=* which seem to have appeared in the wiki without a proposal
and have a few thousand uses.

-- 
Paul
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Re: [Tagging] How to tag flood prone points and areas?

[Warin]

On 1/9/19 10:30 am, Graeme Fitzpatrick wrote:



On Sat, 31 Aug 2019 at 20:51, Paul Allen > wrote:


Verifiability is a problem.


Near here, there's one office building built lake-side, that has a car 
park as the ground level of the building. The car park has a line 
painted round it, about half way up the wall (1.2 - 1.5 m's) labelled 
as the 1-100 year flood level.


Another river side shopping centre has signs down the river end of the 
car park, warning that that part of the park floods during heavy rain.


The first one is only a potential, so you wouldn't map that as flood 
prone, but you would the second, but how?


You could add flood_prone=yes to the car park tag but that will show 
the whole car park as affected, whereas it's only the bit down this 
end that has a problem. Would drawing a separate area & marking that 
as flood_prone=yes work?




I asked this question some time ago. I was told it was not verifiable 
and therefore not for OSM.



My opinion remains - it can be mapped.


However there is the question of frequency, once in 10 year event, once 
in 100 etc. So I would add a sub tag or value about frequency of the 
event.. The key frequency is already in use. Period has some use too, 
though the use looks to be years.. no wiki to say what it is?


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Re: [Tagging] How to tag flood prone points and areas?

[Graeme Fitzpatrick]

On Sat, 31 Aug 2019 at 20:51, Paul Allen  wrote:

> Verifiability is a problem.
>

Near here, there's one office building built lake-side, that has a car park
as the ground level of the building. The car park has a line painted round
it, about half way up the wall (1.2 - 1.5 m's) labelled as the 1-100 year
flood level.

Another river side shopping centre has signs down the river end of the car
park, warning that that part of the park floods during heavy rain.

The first one is only a potential, so you wouldn't map that as flood prone,
but you would the second, but how?

You could add flood_prone=yes to the car park tag but that will show the
whole car park as affected, whereas it's only the bit down this end that
has a problem. Would drawing a separate area & marking that as
flood_prone=yes work?

Thanks

Graeme
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Re: [Tagging] How to tag flood prone points and areas?

[Alessandro Sarretta]

Dear Immaculata,

if you want to describe "things" that are prone to floods, it seems to 
me that the tag /flood_prone=yes/ can be the right one.


I have a few doubts on how this information has been collected: are 
there official maps with areas prone to flood and you have selected 
assets in that area or you interviewed people who told you that some 
specific assets were impacted by floods in the past?


If the second is true, verifiability and return times are important 
issues that have to be tackled and somehow mapped.


Ale

On 31/08/19 05:21, Immaculate Mwanja wrote:

Hi there!

In the summer of 2018, we conducted a project called Assets and 
Threats mapping 
under 
the Ramani Huria project in Dar es Salaam, Tanzania that aims to make 
Dar es Salaam a more flood-resilient city. In this project, we focused 
on the assets/amenities in the city that are important to the 
community and are at risk of flooding or not.


After collecting all the information, we decided we should upload them 
in OSM to be shared with the world since it was a successful project 
to some extent. The challenge came when we could not upload these data 
since there is no specific tag to use for amenities or AoIs affected 
by floods, the only tag that we could find is flood_prone=yes 
but this is 
mostly applicable to “roads/ways" that go underwater after heavy rains.


 1. Is there any other tag that can be used for points under flooding
threat or can we use another tag?
 2. Our initial thought was to create a new tag i.e. asset:risk=yes
and asset:risk=noor we could overcome this challenge by having one
tag that is used by the entire OSM community to identify ways,
areas, or pointsthat are prone to floods

Kind regards,
*Immaculata Mwanja*

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Re: [Tagging] How to tag flood prone points and areas?

[Paul Allen]

On Sat, 31 Aug 2019 at 08:30, Joseph Eisenberg 
wrote:

>
> But it's also questionable if entering 10 year or 100 year flood zones
> (places that statistically have a 10% or 1% chance of flooding during
> a 12 month period) into OSM is a good idea. The OSM database is based
> on individual mappers, usually volunteers, entering data based on what
> they can see when they visit a place, or what they can see on aerial
> imagery. It would be difficult for individual mappers to confirm if a
> 10 or 100 year floodplain was entered incorrectly.
>

Verifiability is a problem.  I'm a little laxer than some, so if copyright
permitted I might
accept official government documents as sources.  Probably not, in this
particular
case, but maybe.  But it's not going to render, anyway, which would make it
useful only
to those who know how to use overpass-turbo.

Maybe uMap is the way to go for this.  Or a CSV file of co-ordinates fed
through a bit
of programming to produce a web page using Leaflet.  Either way would give
a slippy
map with pins which can display text such as risk level.

-- 
Paul
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Re: [Tagging] How to tag flood prone points and areas?

[Joseph Eisenberg]

It appears that most features with the tag "flood_prove=yes" are
covered by water on a somewhat frequent basis, perhaps once every year
or two, to once a month, or even more often during a rainy season.

However, I believe most of these features are prone to "flash
flooding", since they are often mapped in dry areas like Australia,
and the description says: "Whether or not the feature is likely to
flood after very heavy rain."

So this tag might be appropriate if the features that you want to tag
are somewhat frequently flooded, like at least once every year or two,
or more often.

If your survey data was more on the basis of "this feature has a 1% to
10% chance of flooding on an annual basis", that is, 10 year or 100
year flood risks, then I would use a different tag, not
"flood_prone=yes/no".

But it's also questionable if entering 10 year or 100 year flood zones
(places that statistically have a 10% or 1% chance of flooding during
a 12 month period) into OSM is a good idea. The OSM database is based
on individual mappers, usually volunteers, entering data based on what
they can see when they visit a place, or what they can see on aerial
imagery. It would be difficult for individual mappers to confirm if a
10 or 100 year floodplain was entered incorrectly.

In contrast, it's easier for mappers to verify if a tag like
flood_prone=yes is correct on a highway if there are signs that say
"flash flood area" or "floodway" or similar, or if the area floods
after every heavy rain and this is common local knowledge.

Joseph Eisenberg

On 8/31/19, Graeme Fitzpatrick  wrote:
> On Sat, 31 Aug 2019 at 13:23, Immaculate Mwanja <
> immaculate.mwa...@hotosm.org> wrote:
>
>>
>> After collecting all the information, we decided we should upload them in
>> OSM to be shared with the world since it was a successful project to some
>> extent. The challenge came when we could not upload these data since
>> there
>> is no specific tag to use for amenities or AoIs affected by floods, the
>> only tag that we could find is flood_prone=yes
>>  but this is mostly
>> applicable to “roads/ways" that go underwater after heavy rains.
>>
> Had a read of the tag & while it does say roads & ways, I can't really see
> any reason why you couldn't use it for other POIs?
>
> Thanks
>
> Graeme
>

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Re: [Tagging] How to tag flood prone points and areas?

[Graeme Fitzpatrick]

On Sat, 31 Aug 2019 at 13:23, Immaculate Mwanja <
immaculate.mwa...@hotosm.org> wrote:

>
> After collecting all the information, we decided we should upload them in
> OSM to be shared with the world since it was a successful project to some
> extent. The challenge came when we could not upload these data since there
> is no specific tag to use for amenities or AoIs affected by floods, the
> only tag that we could find is flood_prone=yes
>  but this is mostly
> applicable to “roads/ways" that go underwater after heavy rains.
>
Had a read of the tag & while it does say roads & ways, I can't really see
any reason why you couldn't use it for other POIs?

Thanks

Graeme
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