[Talk-us] Potential data source - NY DEC points of interest

Adam Franco adamfranco at gmail.com
Fri Dec 2 23:32:27 UTC 2016


Thanks for the detailed feedback, Kevin! My experience has been mostly in
the St Regis Canoe Wilderness. In that area I've found the campsites and
lean-tos to be quite accurately placed, at least within the error of the
low-quality GPS I was using during my visit. As an example, I've uploaded this
GPX track <https://www.openstreetmap.org/user/Adam%20Franco/traces/2316592>
(I didn't get out of the boat to mark points unfortunately) of a canoe trip
where I scouted a number of campsites. Here's screen-shot of this track
(red) overlaid with the DEC points and trails:

[image: Inline image 1]

All of the campsites I passed seemed accurately placed, as were the trails
I walked -- though some other trails in the area were low-res lines that
can't be correct.

Given the scattered nature of these canoe-access sites it would be quite a
project (realistically impossible for me when making 1-2 trips per year to
the area) to verify them all. It might be worth me reaching out to the
local ranger-station (or equivalent) to see if they can speak to their
process for updating the data as they open/close primitive sites. Maybe an
area-by-area investigation or semi-automated process would be more useful
than a state-wide import.

Much to think about. :-)

On Fri, Dec 2, 2016 at 3:54 PM, Kevin Kenny <kevin.b.kenny+osm at gmail.com>
wrote:

> On Fri, Dec 2, 2016 at 2:40 PM, Adam Franco <adamfranco at gmail.com> wrote:
>
>> Hello all,
>>
>> After doing a bit of hiking and canoeing in the Adirondacks this summer I
>> noticed that OSM has very poor coverage of campsites & lean-tos, something
>> I'd find particularly useful. The New York DEC POI shapefile
>> <http://gis.ny.gov/gisdata/inventories/details.cfm?DSID=1258> has the
>> locations and details of these available and regularly updated.
>>
>> Before going down the road of putting together an import proposal I
>> wanted to find out if anyone has information about usage grants for the DEC
>> data sets. From following this list I've heard that Kevin Kenny has
>> imported other DEC lands shapefiles for the park and area boundaries:
>> https://lists.openstreetmap.org/pipermail/talk-us/2016-May/016290.html
>>
>> Do you Kevin [or anyone else] know if permission to use DEC lands also
>> applies to other DEC data sets or if additional permission would be needed?
>>
>> I've added an entry about this data souce to the OSM Wiki's Potential
>> Datasources page
>> <https://wiki.openstreetmap.org/wiki/Potential_Datasources#New_York> and
>> would like to update it with more concrete information either from
>> usage-grants already received or by making a new request to use the data.
>>
>> Any info or feedback on this datasource would be appreciated.
>>
>
> Thanks for taking an interest in New York! We surely have a massive
> mapping problem/opportunity here: a park that's larger than some European
> countries, with a population of only 130,000, most of whom have no Internet
> access. Hard to get it mapped, to say the least!
>
> Please do NOT import the DEC PoI file; not from a legal perspective, but
> from a data quality perspective.
>
> I do use it as a data source in my personal map because of spotty OSM
> coverage (as you observe), but as OSM has been improving, I'm about to
> discard it. A typical example of what I'm talking about is visible at
> http://kbk.is-a-geek.net/catskills/test3.html?la=42.0966&lo=-74.5095&z=14
> - showing Rider Hollow in the central Catskills. I show point-of-interest
> icons from both OSM and the DEC PoI file, and trails from both OSM and the
> DEC Roads and Trails file.
>
> The 'parking' icon at the end of the county road from Mapledale is in OSM
> and is correctly spotted.
>
> The 'campsite' icon that underlies it is data from the PoI file. I've been
> in there a few times and never spotted a designated campsite anywhere near
> the trailhead. There's a private house no more than fifty feet outside the
> state's property line, and DEC surely would not have placed a campsite so
> close to it (ordinarily they're at least a quarter mile from habitation).
> There's probably a marked campsite in there somewhere. I've never tried too
> hard to find it. There are a couple of splendid spots for 'at large'
> camping in among the hemlocks up in Mine Hollow, and I've just stayed up
> there.
>
> The 'information' icon refers to the trail register, comes from the PoI
> file and appears to be correctly spotted.
>
> The lean-to and associated privy are within sight of the bridge, are from
> OSM, and look to be right. The outline from the building import that Tom
> Hynes did http://www.openstreetmap.org/way/304800815  is kind of
> questionable - either it's some distance from the lean-to, or it represents
> some other building that's long gone.
>
> The parking icon to the south of the lean-to and privy at the 2400 foot
> level is from the PoI file and is obviously wrong. I suspect it is supposed
> to represent the parking where Rider Hollow Road enters the Big Indian
> Wilderness and is digitized from a map at an inappropriate scale (1:250000
> or even smaller). There's a similar problem with the Lost Clove parking
> areas on the NE flank of Balsam Mountain.
>
> The lean-to at the confluence of the three streams is from the PoI file.
> The file names it, so I know it's supposed to be the one by the bridge and
> is placed on the wrong stream junction.
>
> The trails shown in magenta are clearly misaligned. OSM has them right
> according to my GPS. DEC Roads and Trails has them wrong. The Pine
> Hill-West Branch trail definitely follows the ridge through the col between
> Balsam and Haynes Mountains. The Mine Hollow trail makes a wide switchback
> away from the stream to where it joins the Pine Hill-West Branch, which
> does fall off the ridge to the west in the area between Balsam and Belle
> Ayre Mountains.
>
> Not shown on my map, but present in OSM, is a spring
> http://www.openstreetmap.org/node/2845338153 . The PoI file has the
> spring also, incorrectly sited on the east side of the ridge.
>
> I see similar issues in any area where I have (literal!) 'boots on the
> ground' knowledge of the terrain. In my opinion, the file simply isn't
> accurate enough to bother with an import. I've been trying, instead, to use
> it as a 'to do' list - identify PoIs that I want to be sure are in OSM if I
> happen to pass them with a GPS. Lately, in the Catskills, others have been
> beating me to it. Given that I'm just getting back into hiking after over a
> year off with a foot problem, and that I'm starting slow so that I don't
> just wind up back in rehab, I've been focusing on easier hiking in the
> Helderbergs, trying to fill in the gaps in New York Long Path and do some
> more of the little nature preserves along the escarpment.
>
> It could be that there are regions that the DEC has paid better attention
> to - everyone knows that DEC tends to neglect the Catsills. I noticed that
> the agreement with GPS was much better when I thru-hiked the
> Northville-Placid Trail and collected GPS tracks. The major disagreements
> were the relocations at the southern end and the places where our friend
> Castor canadensis has decided that the trail is interfering with one of his
> projects. The worst data problems there were missing campsites and
> shelters. I'd need to see more comparison with data in the field to be
> convinced. Did you collect tracks and waypoints on your outings that we can
> compare with the DEC data?
>
> As far as the legalities go, I was relying on the original permission that
> Russ Nelson got to import the DEC Lands data. I haven't reviewed them in
> detail myself, since all I was doing was to repeat an earlier import to
> tidy up some problems.
>
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