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Published Coordinates for Section Corners
Posted by ryancj31 on June 13, 2021 at 5:02 pmI??ve worked in a few counties with excellent county performed recovery and/or remonumentation of section corners throughout nearly the entire county. One county took 13 years to complete this task.
The county surveyors have made public the coordinates in county coordinate systems from their observations in various forms. Corners that have not been gps??d recently or have questionable coordinates for whatever reason are labeled as approximate or something of the like. In most cases the coordinate data is available in GIS shape files and includes attributes including the date they were shot, and quality of coordinates.
The coordinates are overwhelmingly of very good quality. It??s rare I find one listed as ??survey quality? off more than 0.10 feet. Often within hundredths (I??ve recently stated in another post about dialing up into NGS monument elevations within hundredths as well. Some were shocked. I??m not making this stuff up)
Obviously this is a huge help for coming up with search coordinates property corners. These coordinates have saved massive amounts of time by being able to stakeout to a corners within inches. At worst a few feet from some older surveys.
The question I have is using the section corner coordinates as gospel and never occupying yourself for each survey.
Let??s say you have a simple 40 acre parcel in very hilly and thick country. You need to get 5 section corners to break this parcel down.
All I??ll say is it kinda sucks to spend 4 hours of bushwhacking for section corners just to have your coordinates differ by a couple hundredths on any one corner.
Thoughts?
Mark Mayer replied 2 years, 10 months ago 9 Members · 17 Replies- 17 Replies
Part of our duty is to report conditions, another is to maintain the monuments. A spreadsheet of coordinates is not only useless to owners, it is legally subservient to nearly every other form of evidence.
Coordinates will eventually work thier way up the order of calls. A few places they already have. I don’t work in any and don’t plan to any time soon..
@thebionicman it??s just frustrating to know other surveyors are not taking the time to hunt them down every time.
And to me it seems almost verging on cocky to say my distance on a section line is 0.02?? different then every other survey for the last 12 years.
I guess part of me wishes the coordinates were never published? Or maybe the counties were kinda asking for trouble in doing so? But then again they are trying to build a strong and increasingly accurate framework for all sorts of data to be built on top of not solely for the purposes of land surveyors.
I do understand that if nobody hunts them down at least every once in a while bad things can happen.
I too agree coordinate values will work their way up the order of importance. 5 years? 10 years? Once every one is settled into the new 2022 coordinate system?
IMHO if a corner gets disturbed and needs to be reset I would feel better about its position resetting it from strong observed coordinates while it was still in good condition as opposed to blazes in a 80 year old tree that is now 2x the diameter it was when originally tied to witness blazes.
Just one weak but still pertinent example that comes to mind.
The segment of unethical surveyors unwilling to meet the standard of care is not a new thing. If you could ping a transponder to verify a corner they would avoid pushing the button. It’s in thier nature. That is what discipline is for.
I suspect coordinates will rise slower in some placss than others. The adoption of new datums won’t be the turning point. We already deal will unreliable garbage out of a significant number of practitioners, making it more complex won’t help. It will take a cultural change.
As for your example I gave another take. If the corner has a reliable coordinate and the best accessory is a BT, somebody needs to sell his GPS and buy a highway chain and two plumb bobs. Maybe a metal detector to go with it.
Coordinates can serve several valuable purposes. I have yet to see a device that would provide coordinates superior to decent accessories. Most of our profession points us to interpolate rather than extrapolate. Use verifiable data over independent data. The list goes on. Yes, we will see coordinates rise in the order of calls. At that point I’ll probably hang up my vest.
Whut? Coordinates are fabulous for searching but finding the original monument or restoring an obliterated corner position from accessories trumps any “coordinate” relocation. Coordinates are at the bottom of the hierarchy and maybe be worth considering for “lost” corners but adjacent corners may trump coordinates concerning a truly proportionate resolution.
Concerning local accessories 4′ trees with blazes even if dead are definitive evidence to within a few tenths. An actual bearing tree is definitive. I’m just saying bad coordinates could mess up what’s on the ground and result in clearly monumented positions losing their provenance and suffer from um “coordinate shifts” which could be tens of feet.
GPS surveying is totally cool and results an a few inches accuracy, but that’s not the same as resolving ancient ownership based on record monuments and occupation. Surveying is all local.
Just a talking point………. but wouldn’t a coordinate would make it an obliterated corner? …….
- Posted by: @ryancj31
it??s just frustrating to know other surveyors are not taking the time to hunt them down every time.
Why would you want to put yourself on that level?
I sleep better at night, knowing I did the best I could…
I do enjoy using those published coordinates to calculate where my corners are and finding those corners within a reasonable tolerance.
But if that’s the case; it’s usually not that difficult to find the published monuments…
I hope everyone has a great day; I know I will! @jpb evidence connected to the original monument or a reliable perpetuation thereof would make it obliterated. A coordinate by itself isn’t that. Add the right metadata and you could get there…
Maybe a slightly farfetched example but the following states what my dilemma is on this still relevent but somewhat side topic of restoring section corners based on coordinates:
you have a tie sheet that hasn??t been updated since 1980 perpetuating the bearing trees from 1910. Even though many people have been there over the years including yourself. Everyone who visited saw the 4 bearing trees, some taped in measurements for confirmation but nobody every updated a tie sheet.
Tie sheet shows 4 bearing trees. You find 3 remaining bearing trees and your section corner laying on its side under the forth.
Needing to reset the original monument you find the residuals from pulling arcs from the marked trees give you a triangle about 0.40 wide.
Do you give priority to resetting in the middle of that triangle? Do you use the coordinate you have from 3 years ago which agrees very closely with 10 other surveyors? Do you reset based on distances from adjacent corners? Isn??t that just based on coordinates a half mile away?
In all my years I only recall resetting a few section corners a so I am not too up to speed on procedures. Only one in recent history that I just assisted on. But I have shot in many witnesses to monuments and find a wide degree of accuracy. If anything my dilemma on this side topic is that I do not feel like ancient scribes in a tree are not a precise witness. I much prefer to have pipes or bars as witnesses.
I guess if anything this sums up why we need to visit each corner we use on every map every time despite the temptation of using published coordinates. And also updating tie sheets and adding new contemporary ties for when those witness trees finally fall.
A good coordinate base can be very useful and compelling. But in my mind it boils down to the question, “when are surveyors going to be willing to discount a physical monument in favor of (possibly adjusted) published data”?
200 years of case law says we shouldn’t be so quick to do that.
Consider this scenario – Surveyor Olds has surveyed a certain property and set monuments at the corners. His survey record, and the legal description he prepares includes ties to a number of section monuments. Owner occupies the property, maintaining the monuments and a stout, straight fence bang on the lines.
The County Survey, in subsequent years, recovers, renews, and documents the section monuments, including coordinate. The county surveyors dimensions between section monuments agree with Surveyor Olds dimensions within a few hundreths.
30 years pass and Surveyor Ryan comes along to survey the property again. He uses Surveyor Olds survey record/deed dimensions and the C.S.’s coordinates to figure coordinates for the property corner monuments, all of which he finds, practically spot on.
The state minimum standards require that the survey be tied to a section monument.
Can Surveyor Ryan just rely on the County Surveyors coordinate to show the section monument tie on his survey?
Who made the county survey crew the highest authority in the land? I know I didn’t. Maybe they got it wrong. The stone I find 20 feet away from the calculated position that the county crew decided was right should overrule the published coordinates because IT IS the original stone and fits all evidence other than pure math. Do you think the county crew will agree to admit they made an error and so notify all users of their faulty coordinates of which they are aware? Not likely.
@mark-mayer
If the minimum standards require tying to a section corner monument, you are not meeting those standards unless you measure to a monument. Coordinates are not monuments.
I say just do away with the requirement and let the professional determine when a tie is required.
The accessory is part of the monument and is legally superior to everything other than the undisturbed original monument itself.
If folks have been visiting that corner for over 40 years and nobody updated the corner record, the coordinates by that group are probably as useless as the surveyors are lazy.
In theory a nice spreadsheet with no error would solve many problems. In practice I have yet to see it work.
Another problem arises when the coordinates are not ground coordinates Those who attempt to do everything in state plane coordinates and then write their boundaries using those state plane coordinates are screwing up the cadastre, but they don’t know they are doing that. Black boxes turn peoples brains to mush.
Ooh, ooh, look. Look at the pretty numbers. Pretty numbers are always correct numbers. Never question the pretty numbers on the screen. So what if they tell me this mile is 18427.86 feet long by 40.01 feet wide, the pretty numbers never lie.
In the scenario I laid out both Surveyor Olds and the County Surveyor have surveyed the same monuments at different times and got similar results. What are the chances that they were both wrong to identical degrees?
If Surveyor Ryan knows that either Surveyor Olds, or the C.S. Surveyor, or both, are regular f’ups, then that does change things.
That is a different thing.
If. Typically such standards state that such ties must be shown but are silent on just how they are done.
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