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kayakbird

COUNTY ERROR DETECTION

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Hi All,

 

I am taking some icy road downtime to re-pin my DeLorme Topo North America 9 map program. My DATASHEET files are county based so that's how I download the NGS Shapefiles; having to swap the order of the L/L columns in the process. I also add the name and year set (or year NOT FOUND) information to the PID column. For UNK's I'll make a SWAG to some YYYY.##. With this info right there on the map I can then hi-grade target points when I'm on a random road trip - can't get em all, right!

 

After using this map program for 18 months I have finally figured out that by systematically changing the map pin style, the ones listed with the wrong county stand out like neon signs.

 

Eagerly awaiting dry roads in the Missouri Breaks.

 

kayakbird

Lewistown, Mont

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I've found a few listed in the wrong county. Mentioned one in the threads here, and NGS said that it didn't really care. But, hey, go for it.

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I don't know who at NGS would have told you we don't care but that's not true. Whenever a correction for the state or county has been posted to me I review it and if it's legit I have our database team make the correction ASAP. We have made numerous such corrections from this board over the years. Since one of the NGS database retrival options is by county we want to try and make sure that our information is as correct as possible.

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I don't know who at NGS would have told you we don't care but that's not true. Whenever a correction for the state or county has been posted to me I review it and if it's legit I have our database team make the correction ASAP. We have made numerous such corrections from this board over the years. Since one of the NGS database retrival options is by county we want to try and make sure that our information is as correct as possible.

 

Dave,

 

Thanks for that information. To clarify: do you take table exercise information, or must they have been recovered? With less than a third of Montana re-pinned I'm at 75 with about a dozen more on, or close to, a county line where I may be able to make a determination after reading the Data Sheet.

 

If you can take them all what information do you need? I have them in an Excel file.

 

Maybe I will do something productive while snowbound.

 

Mike

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Mike,

 

Give me whatever you have.Sometimes the error can be very obvious and I will easily accept the correction. Sometimes they can be very close and will require more scrutiny. If it's too close to call we'll usually error on the side of what we have published.

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Dave,

Glad to here that I misunderstood. The one I was thinking of is KV1351, which is in Hunterdon County, NJ, not Somerset.

There are a couple of others where the scaled coordinates seem to have a typo, which puts them in the wrong county. That's probably a trickier problem.

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I have validated that KV1351 (R 25) is in Hunterdon instead of Somerset county. I have sent a change notice to the NGS Records Managment Branch. Hopefully they will get to this in short order.

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It must be a quite day for the NGS Records Management team - KV1351 (R 25) has been corrected. Thanks Harry Dolphin for taking the time and effort to help us make the National Spatial Reference System as perfect as possible.

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Dave:

 

Here are 13 PIDs for Arkansas. They should constitute all of the adjusted marks in Arkansas with an incorrect County Name. I didn't see any point in checking scaled marks(coordinate accuracy) or intersection stations(relevance). I have checked each of these 13 against Bureau of the Census Arkansas county boundaries for 2010 and USGS 1:24,000 topo maps.

 

PID      WrongCounty    CorrectCounty
DG4779     CHICOT         DESHA
DK2001     DESHA          CHICOT
DK2009     DESHA          DREW
DL1575     MILLER         HEMPSTEAD
EH0993     LEE            PHILLIPS
EH2912     MONROE         PHILLIPS
EH3062     PRAIRIE        LONOKE
EH3076     PRAIRIE        LONOKE
EH3117     LEE            ST FRANCIS
EJ1878     PERRY          PULASKI
EJ1911     SALINE         GARLAND
EK0817     SCOTT          POLK
FF1965     MISSISSIPPI    CRITTENDEN

 

Tim

Edited by tosborn

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DV1907 HARQUAHALLA RESET is the highpoint of La Paz County AZ but it's listed in Maricopa County. The county line runs north/south through DV2275, about 3/4 mile to the east.

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DaveD,

 

Would you prefer that mis-assigned states/counties be posted here or emailed directly to you (or someone else at NGS)?

 

Also, do you want supporting data, or just PID and corrected county, as tosborn has posted?

 

-ArtMan-

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ArtMan - I would prefer that corrections be sent to me by e-mail -- dave.doyle@noaa.gov. Please provide the PID and what county you think it belongs in, I will do the rest of the reseach.

 

I have reviewed and confirmed the changes posted by tosborn and southpawaz and I have submitted a database change request to the NGS Records Management branch.

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When I first started benchmark hunting, I had a lot of fun going thru Missouri and finding county errors. For me, it was a nice combination of benchmark research and map research. I know I included scaled marks but I was more careful with them if they kicked out. I think Missouri should in pretty good shape now. I can't remember if I did Illinois or now, maybe I'll look it over.

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Dave & all,

 

Since there seems to be some interest in this activity I'll throw out this question here - how do you want to treat the PID's that are listed with a US county, but are physically located in Canada? I have an incomplete list of at least 64 of these. Would you like them identified by Province and the county that they are directly north of?

 

Such as: TM0867 ALBERTA-GLACIER

 

NOTE: You can't just filter by N 49 00 00.00 LAT. This one is over 500 ft south of there; and some US points are north of that number.

 

In Montana there is a "county" for Yellowstone National Park but not Glacier NP. Maybe each state could have a "north of the Medicine Line" county.

 

On including scaled mark I believe some professionals weighed in on a previous thread that in the near term 'future' of using existing points, Bench Marks will continue to be very important.

 

kayakbird

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I've been waiting for the Medicine Line issue. I'll be interested in Dave's input.

 

Cheers! :)

A bunch in Maine, NY and Vermont are like that. They're all IBC marks or marks set by GSC which were used by the IBC. They're placed in the nearest US county, which woks fine for someone like me who understands what is going on, but for someone unfamiliar with the situation it could be confusing.

 

I think the best was this one Hereford, QH0620

 

A beautiful stamped copper bolt (a first order station) set in 1909 by the GSC and used by the IBC in it's triangulation of the border in 1915. It's one of several points used to tie the border triangulation with the triangulations of the US and Canada, and thus tied those two national triangulations together. Here it is:

 

2e15493c-403e-48ed-8d6b-11501079ed4f.jpg

 

Although only a 3/4" bolt, they managed to stamp "GSC" and "1909" on it, together with a circle and a tiny cross at the datum point.

Edited by Papa-Bear-NYC

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For kayakbird - I hesitate to change the geographic designation for stations such as you mentioned as we have a general policy to not publish data for passive marks in Canada. If we change the country/county/province designation then they will immediately become unpublishable. I would let sleeping dogs lie.

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I would let sleeping dogs lie.

 

Sounds good to me. For general interest most of the ones north of Montana are not listed with the adjacent county; and the locations that I visited last summer were neither logged or recovered (only found one out of about 15). Below is a link to a thread from last year on this subject. MEL

 

Canadian Benchmarks

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We are about to side track this thread just a little. We were out benchmarking and found a glaring error that had us drive an extra 20+ miles to be sure we had found the benchmark described on the datasheet. We stopped for C 368 and became a bit confused when we saw the stamping on the disk.

 

65b40178-8600-4de0-9e54-76ae669b78a7.jpg

 

e040e8b1-6efb-4d69-957a-d51f03bebcbf.jpg

 

2 different disks with the same stamping - C 367. The top picture is the 1 at the described location for C 368 and the bottom picture is the 1 for C367. Both are in Kane County Utah.

 

After finding C 368 we found B 368, A 368 & Z 367. Then we drove to where C 367 was supposed to be located and sure enough it was in that spot.

 

We checked the NGS datasheet and it says the disk should be stamped C 368 not C 367.

 

Just thought you might want to have someone verify what we found and have the datasheet corrected.

 

John

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Just thought you might want to have someone verify what we found and have the datasheet corrected.

John

 

Looks like a clear case of a field stamping error. I would add a recovery remark to both PID's indicating that the erroneous disk is in sequence on this level run which started at the western edge of Kane County and went clear to the southeast corner. MEL

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65b40178-8600-4de0-9e54-76ae669b78a7.jpg

Your PN-40 is far, far too clean. Those IN.OUT buttons don't even LOOK worn!

 

Get out more! :)

 

They ALWAYS wear latex gloves when handling the unit. ;)

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Is it me, or does that one look a little more convex than usual?

 

Good eye, Duke. That style of disk does have a much higher crown. Seems like they started showing up in the early 80's. kayakbird

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Is it me, or does that one look a little more convex than usual?

 

Now that is a real dome question! ;)

 

All the vertical control disks from 1983 in this area have a high dome to them. We haven't seen any others that were that convexed, either earlier disk or later disks.

 

John

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I have a mark that may be NGS-listed in the wrong (adjacent) county. When I recovered the mark I got the GPS coordinates (HH2). Can anyone suggest an online map with county boundaries so I can confirm which county it is in based upon the coordinates?

 

Thanks,

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http://www.mappingsupport.com/p/gmap4.php?z=15&t=t2&icon=ch&ll=36.15438,-94.23657

 

Replace the coordinates at the end of the above URL with your hand-held coordinates (lat,lon) and view in your browser. A crosshair icon will be placed on the map at the location of your coordinates.

Edited by tosborn

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I have a mark that may be NGS-listed in the wrong (adjacent) county. When I recovered the mark I got the GPS coordinates (HH2). Can anyone suggest an online map with county boundaries so I can confirm which county it is in based upon the coordinates?

 

Thanks,

I've been using GPS Visualizer, which allows you to upload data in any of a variety of formats, and display the point(s) or a map.

 

The maps available include the usual (Google maps, USGS topo) as well as others ... including a bare map of county outlines.

 

I would not consider that definitive, however. I've been working on a fairly large group of suspected wrong-county PIDs, and my protocol has included using the county outline map just for the initial cut , then plotting on a USGS topo map (which usually has pretty authoritative boundaries marked), reviewing the description text (e.g., for street intersections), and in some cases checking my best assessment of the location of the mark against municipal or county GIS information posted online. If everything confirms a new county assessment, I'll report it. If there are discrepancies, I won't (or at least I'll flag it in my report).

 

good luck,

~ArtMan~

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I have a mark that may be NGS-listed in the wrong (adjacent) county. When I recovered the mark I got the GPS coordinates (HH2). Can anyone suggest an online map with county boundaries so I can confirm which county it is in based upon the coordinates?

 

Thanks,

 

I use randmcnally.com which can be surprisingly accurate. It shows county boundaries down to the lowest zoom level. If you go to the home page and then click the "Online Maps" radio button, you can enter coordinates. I use decimal coords and those work, I've never tried DM or DMS.

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Montana Trivia - rough draft

 

250 + total errors

81 IBC's - 27 of these listed in Teton Co, which lies sixty miles south of the Medicine Line.

54 Valley County

2 in Roosevelt belong to LEWIS & CLARK Co, 317 miles to the WSW.

 

kayakbird

Edited by kayakbird

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Illinois trivia - first pass:

57 potential problems

52 confirmed including one that is 13 feet east of the state line in Indiana

email sent to Dave for correction

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Multi-state trivia

 

188 submissions total, mostly in Virginia

 

121 that should be in City of Richmond, Virginia, but which are erroneously

listed in Chesterfield County, an adjacent suburb. At one point the

area was in the county, but that was before the city annexed the land.

(I believe the annexation was related to efforts to remedy school

segregation, but I haven't researched this enough to confirm it.)

 

3 listed in Richmond that should be in Chesterfield. In Virginia, it

should be noted, there are a bunch of cities that are independent,

county-level jurisdictions. So Richmond is not part of any county.

 

54 listed in Fairfax County that should be in the City of Alexandria,

City of Falls Church, Arlington County and, in one case, Washington,

DC. That last one is on Columbia Island, adjacent to the Virginia

shoreline of the Potomac River, but an historical anomaly places

the boundary along the Virginia shoreline (not down the middle of

the river, which is usually the case). The island is considered to

be in the river channel, so DC gets the island.

 

4 in New Jersey

 

3 in Maryland

 

1 in Missouri, with respect to RogBarn, who we thought got 'em all.

Apparently, this mark (JC1817) used to have incorrect coordinates,

which placed it in the wrong jurisdiction.

 

~ArtMan~

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