In editing my area I noticed a fire station that wasn’t correct, I figured it was stray information and deleted it. Yesterday I found more! I did not delete those and am wondering if the whole layer needs to be shifted. An example is:
Baltimore County Police Department Precinct 06 Towson
source USGS Geonames
gnis: county Baltimore
gnis: feature 2087319
It appears in totally wrong county and miles and miles away from it’s actual location. I can go back through my history and put back the one I deleted, or should we see about shifting the whole thing, or delete each one of them. There are police stations (also in the wrong county) on the map too.
I see a bunch of these GNIS errors as well. The easy cases are where they are mis-located by a few dozen meters, and they should just be moved to their correct position. I haven’t found that the amount of shift is consistent; so I don’t think an whole layer can be shifted for that case.
For the case of many miles of error, it is interesting to see if the original gnis was wrong - search for the lat/lon at http://geonames.usgs.gov/pls/gnispublic/f?p=101:1:3701910930614165 . It appears that the OSM data matches the GNIS data, so the import was done correctly. I’m thinking that the data is either historical or there was a projection mismatch during some original GNIS data import. The easiest resolution will be to work with a mapper in the location where the POIs belong to shift them. Also, POIs for your area may be located in another zone. If there was a state or countywide problem with GNIS data, there might be some automation that can be applied.
It's important that the POIs not be deleted unless they are historical. GNIS is one of the few consumers of OSM data; if we correct the location of a GNIS POI, those corrections are fed back to GNIS. Similarly if you create a detailed mapping of a GNIS POI by creating an area, copy the tags from the GNIS node to the area before deleting it.
Thanks Mike for that link, I’ve looked at a bunch of different gnis police and fire departments in the state and they are not consistently off, so it’s not an importing problem it is a gnis problem. The ones that are wrong are off by about 30 miles and in some cases are even in the wrong state! I am going to see if I can put back the one I deleted. They are consistently Northwest of where they should be, but just looking at the group of 15 police departments in Baltimore County 7 of them are wrong.
GNIS has the wrong lat/longs.
I started looking for a way to correct a road that appeared on my Garmin through my property and now look what I’ve got myself into!!
Fortunately, the error in the Garmin is not from OSM and I haven’t found where the error originated from, but somebody drew a road through one of my ponds.
Interesting, before undeleting (was 3 according to my history) I checked for their correct locations. They do appear correctly on the OSM map! And I found were they were listed on GNIS search corrected but the old wrong one was never deleted. So the data was imported correctly hopefully GNIS will delete the erroneous ones.
Is there a chance they would ever be imported from GNIS again?
Well I contacted GNIS and this is their answer to me.
"Thank you for this notification. We have initially checked a random
sample from each of your files, and have found some to be located where
they are supposed to be located, and others that are indeed errors. So,
we shall analyze this in detail and get back to you when we have completed
the analysis. Thank you once again for your interest in the Geographic
Names Information System (GNIS), the nation’s official geographic names