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well, here's a new problem

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(@flyin-solo)
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got hired to lay out lot corners in a recently recorded phase of a subdivision (how we got here is too long and not particularly relevant to the question at hand).

as per changing requirements, SPC coords are listed on the plat for POB and a couple other corners.  day one, we go out and shoot in a bunch of rods to check, as well as a good chunk of built-out C&G in the new phase (which, roads are in, finish grading is done, they're ready to start building).

here's the deal: none of the boundary found along the perimeter, nor up the road leading in (also platted by the same firm) matches stated coords. found now fewer than 3 firms caps out there (including the firm that recorded the plat).  it's all reasonably consistent within itself, but from off the SPC values by 0.7-1.3' (across a couple thousand feet).

so, what holds?  just for the sake of argument, let's assume all the other firms vaporized yesterday and there's nobody to call to figure out who knows what and/or why this discrepancy is here.

i know what i would have done if i'd run into this with no stated SPC- best fit to the found monuments and set corners.  funny when i do that- the built streets are suddenly dead-ass centered between my calcs, instead of a foot+ discrepancy on BOC ties using stated coords...

just wondering where this requirement for coords falls now on the whole priority of calls...

 
Posted : April 7, 2020 8:11 am
(@andy-bruner)
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Question.?ÿ Are you staking property corners or State Plane Coordinates??ÿ For the past 50 years or so I've been taught that any verbiage (or coordinates) are only there to get me to the corner.?ÿ I don't mean to be snarky but some bureaucrats just plain don't understand what surveyors do.

With that being said I WOULD ask the client about re-recording the plat with the correct coordinates shown, if that is what is required.

Andy

 
Posted : April 7, 2020 8:18 am
(@flyin-solo)
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@andy-bruner

that's the phase of the conversation that was lobbed this morning.  client is, presumably, throwing coffee mugs at techs right now. (just kidding- he's actually an old boss and a really reasonable guy.)

 
Posted : April 7, 2020 8:23 am
(@nate-the-surveyor)
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Under the bosses desk. If wernt for idiots like you, nobody would be the wiser..... (Kidding there)

Did you wash her hands?

I'm sort of kidding you, but I once published wrong SPC on a project.

So, do what you should do. Ignore those coords, and hold them pins. Priori of calls.

Maybe he BIG error eclipses, with his 15 minute tie to cors. Um spell check never seen an ellipse!

N

 
Posted : April 7, 2020 8:24 am
(@bill93)
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What's the Combined Scale Factor for this location??ÿ Somebody may have had a design factor with no metadata, so they aren't true SPC.

Or they may have done a "Here" calibration with their GNSS without being properly settled in.

Monuments over coordinates, for sure when the points fit together well.

 
Posted : April 7, 2020 8:25 am
(@ric-moore)
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coordinates will always change.?ÿ Unless reliable evidence can support otherwise, the location of the undisturbed monuments will control.

 
Posted : April 7, 2020 8:44 am
(@holy-cow)
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Oh, for the good old days.?ÿ One standard unit and one way to measure.

 
Posted : April 7, 2020 9:15 am
(@bill93)
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Posted by: @holy-cow

Oh, for the good old days.?ÿ One standard unit and one way to measure.

... and a foot in a mile was good work.?ÿ We're worrying over a whole lot less now.

 
Posted : April 7, 2020 9:20 am
(@williwaw)
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Posted by: @flyin-solo

just wondering where this requirement for coords falls now on the whole priority of calls...

Are we now living in Bizzaro Land, where up is down, left is right, and coordinates hold over found monuments? It's all so surreal. Sigh

My WAG is the subdivision wasn't done in SP but the coordinates were computed later to check some box and don't control bubkis.?ÿ

 
Posted : April 7, 2020 9:37 am
(@flyin-solo)
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@williwaw

wanna guess what 3 letters most likely caused the thing that caused the problem that caused me to ask the question?

 
Posted : April 7, 2020 9:45 am
(@aliquot)
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This is not a new problem. This isn't different than the old "problem" of bearings and distances versus monuments.

?ÿ

 
Posted : April 7, 2020 10:07 am
(@aliquot)
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Posted by: @williwaw
Posted by: @flyin-solo

just wondering where this requirement for coords falls now on the whole priority of calls...

Are we now living in Bizzaro Land, where up is down, left is right, and coordinates hold over found monuments? It's all so surreal. Sigh

My WAG is the subdivision wasn't done in SP but the coordinates were computed later to check some box and don't control bubkis.?ÿ

This was my initial response too, but are we missing something? This sounds like Survey 101.

 
Posted : April 7, 2020 10:12 am
(@flyin-solo)
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@aliquot

 

yeah, i know.  me too, just... well, let's just say the circumstances here are unique.  i'm not holding the coords, btw.  this is just a scenario where i've stepped in at an awkward spot in the whole process (way more than i'd anticipated), and there are 3 entities all waiting anxiously for me to get them bailed out from a firm going under or going left or whatever happened to them.  there's a civil firm (my actual client), the developer, and now the big-time home builder with a fleet of equipment lined up at the entrance to this place waiting to start forming up slabs...

 
Posted : April 7, 2020 10:25 am
(@flga-2-2-2-2-2-2-2-2)
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Posted by: @flyin-solo

best fit to the found monuments and set corners

That's the best way to do it! Nobody cares about coordinates inside a platted subdivision. If they do they will find that in the grand scheme of things they are losing money on such frivolous details. ?????ÿ

 
Posted : April 7, 2020 11:20 am
(@nate-the-surveyor)
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Throw those coords in the trash. Was meant. Typing on tiny keyboard. With sp chk. Goofs it all up.

 
Posted : April 7, 2020 11:58 am
(@thebionicman)
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Found oroginal monuments or reliable perpetuations of their positions, followed by record dimensions, followed by proportion, then MAYBE followed by coordinates (but probably not)....

As Mr. Robbilard said (quoting Brown I believe), the owner could care less if his property relates well to some distant control point...

 
Posted : April 7, 2020 2:20 pm
(@bstrand)
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Coordinates are at the absolute bottom of the list of priority of calls, iirc-- less significant than even acreage.?ÿ I've always thought it was dumb that they were required on surveys anyway because what is a lay-person going to do with them??ÿ Everything else on a survey can be utilized by farmer Joe with a compass, pacing and a set of eyeballs.?ÿ But coordinates??ÿ Dumb...

 
Posted : April 7, 2020 2:43 pm
(@flyin-solo)
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@bstrand

this is undoubtedly a GIS driven requirement. 

and @thebionicman

that's the ONLY thing giving me any kind of pause- when we speak of "original" we (i believe) usually assume something with a nice bit of ripening to it- this entire development has been designed, platted, graded, built out in the past 12 months.  we found rods set by no fewer than 3 different firms- even the one who did the plats.  so this is all warp speed kind of stuff.  problem being the firm who platted it is... let's just say i don't know enough to know any more than they can't solve or fix this issue, either in the timeframe required or at all.  it's unclear as to what the status of that business is as of today.  bottom line- they got canned and somebody (me) gets to go in and make sense of things.

 
Posted : April 7, 2020 2:58 pm
(@murphy)
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Hold the monuments and accurately tie your work to SPCs.

I'm a firm believer in Grid ties. I've taken the time to get to know a few of the GIS techs around NC. Most of them care about getting things right and are aware of the limitations of fitting floating descriptions on spatially referenced maps. Providing accurate Grid ties helps them make an already useful map into a great aid to landowners, designers and planners.?ÿ I provide clients with an overlay of their boundary on an ortho-image.?ÿ The positive feedback from this makes it difficult for me to undervalue the importance of seeing a boundary in relation to Earth's surface.

 
Posted : April 8, 2020 1:49 am
(@mightymoe)
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Report measured and record, the monuments control.?ÿ

?ÿ

?ÿ

?ÿ

 
Posted : April 8, 2020 7:17 am
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