[Talk-us] dubious church node

[Brian May]

On 9/29/2017 11:06 PM, Kevin Kenny wrote:
> On Fri, Sep 29, 2017 at 9:33 PM, Mark Bradley 
> <ethnicfoodisgreat at gmail.com <mailto:ethnicfoodisgreat at gmail.com>> wrote:
>
>
>     In the course of my mapping in the American Midwest, I have come
>     across several small country churches of GNIS origin that no
>     longer exist.  Often there will be a nearby cemetery, but the
>     church facility is gone.  I simply delete the node.  In one case I
>     know of, the church building was converted into a home, so I
>     remapped it accordingly.
>
>
> Of course, if the cemetery is there on the ground, then it should be 
> mapped. But deleting the node for a demolished church is entirely 
> appropriate. For a church converted to a private home, consider:
>
> building=detached historic:amenity=place_of_worship historic:name=* etc.
>
> if the building still resembles a church.
>
>
For any arm-chair mappers out there, you cannot assume the location of 
the original GNIS point is accurate at all, unless you have up to date 
evidence it is. So if you see a church point sitting on what looks like 
a house in a residential neighborhood on the aerial, then either delete 
it,  mark it as a FIXME or leave it alone. The person working for the 
Feds who originally mapped the point may have been miles off.

A few thoughts:

Churches from GNIS seem to be one of the biggest "map noise" features 
for areas I look at. Sometimes the locational accuracy is spot on, 
church is still there and everything is great. Sometimes the church is a 
mile and half down the road on a different block. Sometimes its in the 
middle of the highway. Sometimes in the water, etc. When I am quickly 
reviewing an area and I see a church point in the water or on a road, I 
usually just move it to a halfway plausible location without doing more 
research. It would be nice to have a fairly solid process for reviewing 
these with external data that is of known high quality.

I did a little playing around with the new USGS Map VIewer [1] and it 
has a Structures layer.  This appears to be part of the volunteer corps 
thing w/ USGS, which was (is?) a national program to provide higher 
accuracy points focused on buildings and structures.  I found this [2] 
from 2012 that provides an overview. Looks like they intended to 
contribute back to OSM - but no word on that in the doc. Found this site 
as well [3], but out of time to dig into it for now. Anyone know more 
about this Structures layer?

In the USGS Map Viewer, you can click on a structure and see details 
about it. Some say source=centroid - to me this means parcel centroid. 
Many have addresses as well. The map viewer allows you to switch the 
base map to OSM. So then you get a nice QA tool to check OSM features in 
an area. The structures layer doesn't include churches, but cemeteries 
are included. Other features include Post Offices, State Capitol 
Buildings, Hospitals / Medical Centers, Police Stations, Prisons, 
Colleges, Technical Schools, Schools, Campgrounds, Trailheads and 
Visitor Information Centers.

I have a statewide parcels layer that just shows church polygons and 
labels that I use sometimes use as well for checking churches - others 
are welcome to use it if interested.

[1] https://viewer.nationalmap.gov/advanced-viewer/
[2] https://pubs.usgs.gov/of/2012/1209/pdf/ofr2012-1209.pdf
[3] https://nationalmap.gov/TheNationalMapCorps/#

Brian
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