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Grid Ties

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(@landman)
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I thought the purpose of and the requirement for grid ties was for retracement and I always try to base all of my boundary surveys on grid, making it really easy to follow.  However, lately it seems that a lot of the surveys that I'm following show a grid north arrow but no grid coordinates or tie to a grid monument.  Is this keeping the coordinates "in house" on purpose or an oversite?

 
Posted : November 4, 2024 10:53 am
Norman_Oklahoma
(@norman-oklahoma)
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I might establish control and basis of bearings for a boundary job by reference to a VRN, or by getting an OPUS position for my GPS base station. Neither of these methods involves a local brass "grid monument". Especially in the case of the VRN there is no singular monument to point at. Even if I position my GPS base with an instantaneous autonomous position I'll still have a "grid" basis of bearings. These are all valid means to the intended end.

Tying any survey to a physical brass grid monument would be rather inconvenient in my area. There are very few still in existence, fewer still in GPS'able locations.

 
Posted : November 4, 2024 2:56 pm
(@landman)
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So if you establish control via VRN or OPUS solution why not show the grid coordinates on the survey?

 

 
Posted : November 4, 2024 9:30 pm
MightyMoe
(@mightymoe)
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I only show Lat Longs on my surveys for filing. NAD 1983 (2011), Or NAD 1983 (1993) are examples. As far as "grid" what "grid"? Unless you're surveying true north all the points have some type of "grid". 10,000 x 10,000? That's grid. UTM? State Coordinate System? 

We've been doing this a long time, the older State Plane coordinates don't hold up very well. I frankly would rather not see them on a plat, newer ones are much better once GPS came along, but tying to NGS monumentation set out for NAD27 is always problematic and moving forward the coordinates are going to become moving targets.

If you're going to do coordinates today, lots of metadata should be published on the face of the plat.  But the coordinates can never be authoritative. 

 
Posted : November 4, 2024 10:26 pm
thebionicman
(@thebionicman)
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Including coordinates on the map only reinforces the math over monuments mentality. For many it is an excuse to avoid observing important evidence.

 
Posted : November 5, 2024 12:03 am

(@wa-id-surveyor)
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Coordinates are near the very bottom of the hierarchy of data.  Unless required by an agency, they will never be on my recorded documents.  WA makes it so painful and burdensome (big surprise) that I'd be shocked if anyone ever put coordinates on a recorded document.  ID is significantly more flexible in this regards.   

 

 
Posted : November 5, 2024 1:09 am
(@murphy)
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Older topic but still relevant.  I don't care what state I survey in, I'm going to provide the means to anchor my client's boundary to planet Earth.  Natural disasters happen, such as the massive flooding in Western NC or the Maui fires.  I can't control what an incompetent surveyor will do with my plat.  I can, however, make sure that in the unlikely event that a flood, fire, earthquake, or volcano destroys everything, a competent PLS can grab a GNSS receiver and reestablish the boundary without much guess work.

 
Posted : November 17, 2024 9:58 am
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Norman_Oklahoma
(@norman-oklahoma)
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Posted by: @landman

So if you establish control via VRN or OPUS solution why not show the grid coordinates on the survey?

Because, here in Oregon, a recording state, the County Surveyor reviews submitted surveys very carefully. Showing coordinates is allowed, but not required. Adding them would introduce a whole new layer of information that the CS could review and critique - adding costs and time to the process. It's a case of the perfect being the enemy of the good. 

 
Posted : November 20, 2024 12:10 pm
(@landbutcher464mhz)
Posts: 19
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Posted by: @murphy

Older topic but still relevant.  I don't care what state I survey in, I'm going to provide the means to anchor my client's boundary to planet Earth.  Natural disasters happen, such as the massive flooding in Western NC or the Maui fires.  I can't control what an incompetent surveyor will do with my plat.  I can, however, make sure that in the unlikely event that a flood, fire, earthquake, or volcano destroys everything, a competent PLS can grab a GNSS receiver and reestablish the boundary without much guess work.

Exactly what we do. All of our Parcel Maps and ROS Maps are tied to NAD83. Those NAD83 coordinates make it easy for the next guy to get within a foot to find enough recorded points to start reestablishing the boundary. I do it all the time to find other surveyors pins and even with NAD27 and UTM when necessary.

This post was modified 7 days ago by Landbutcher464MHz
 
Posted : December 1, 2024 11:06 pm
1
Norm
 Norm
(@norm)
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Coordinates along with one or two validation monuments on a project is good. Coordinates with no validation monuments is risky because coordinate systems are abused, misused and too often misunderstood. Hopefully over time licensed surveyors are improving their competency in working with coordinate systems tied to geodetic datum by necessity and by learning the hard way. Not that I know anybody like that.


GIF
 
Posted : December 2, 2024 8:12 am

Williwaw
(@williwaw)
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Posted by: @thebionicman

Including coordinates on the map only reinforces the math over monuments mentality. For many it is an excuse to avoid observing important evidence.

I want to agree with you, but I think that blanket statement overlooks coordinates as another tool to help someone following to get back in your footprints to lead them to the monument's original location. Coordinate ties or at a minimum, a 'basis of coordinates' along with meta data, can be a very useful tool to someone attempting to follow your survey and if those monuments are gone, they are far more useful than nothing at all and having to resort to proportioning to put the monument back where they were most assuredly not located in the first place. I've gone back to monuments I surveyed in years before and found them replaced after being disturbed, sometimes feet from where I originally located them and when I question the surveyor that placed them, the story is nearly always the same, 'I proportioned it back in following the rules.' Now what? 

 

 
Posted : December 2, 2024 9:55 am
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(@bstrand)
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Posted by: @landman

show a grid north arrow

Whoa, I don't know if I've seen a grid north arrow before.  How can you tell it's not a geodetic or magnet north arrow?  😏

 

Posted by: @landman

tie to a grid monument

What is a grid monument?  Do you mean an NGS monument?

 

I don't put coordinates on my surveys at the moment for a few reasons most of which have been mentioned.  Last I checked it's ranked the lowest form of evidence (even below area) which would make me unlikely to reset a corner from it, and even if it were on a survey I was referencing I'd have to calc a point for it which is what I'm already doing with the bearing and distance calls... so I don't know that it would save me any time.

I don't think it helps the public really at all at the moment since smartphone GPS isn't good enough to make meaningful use of the data, but that's not to say it couldn't be useful in the future assuming consumer grade gadgets get more accurate.

Ultimately, I think it's like having too many elements of a curve on a survey; at a certain point the excess data creates conflicts that didn't need to be there.

 
Posted : December 2, 2024 2:43 pm
OleManRiver
(@olemanriver)
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I have seen a north arrow that states simply grid.  Also just the datum aka NAD83.  Then others that state NAD83 state coordinates and zone.  META data is very very important at least for me. When I see nad83 only the first thing that comes to my mind is geodetic north. I have learned I should assume its grid north. Which again META data is important. The same goes for placing coordinates such as state plane UTM or geodetic lat and longs. State the META data. Way to many surveys I have been involved with in the last few years where someone scaled state plane to ground stated grid north but the coordinates after reverse engineering them prove to have been scaled from some location on site or about 0,0. I keep and give the lat long and the ellipsoid height or orthometric height that I use to scale any coordinates to ground along with the combined factor.  Every project I work on that information is readily available. Along with the other meta data. Units datum etc etc. if I were stamping I would prefer lat long on POB and some corners a note and such stating datum etc. doesn’t matter then what new datum’s come out easier to perform the transformation and get to whatever system I choose.  But they are still just a portion of the information needed. 

 
Posted : December 2, 2024 10:00 pm