On 9/29/2017 11:06 PM, Kevin Kenny wrote:
On Fri, Sep 29, 2017 at 9:33 PM, Mark Bradley
<ethnicfoodisgr...@gmail.com <mailto:ethnicfoodisgr...@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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