I'm about to begin work on a waterline project that is mainly in Texas, but extends into a Section in New Mexico. The person signing and resolving boundary is licensed in both states. I'm wanting to keep this in one basefile and everything we have in historical data is in the Texas Plane Coordinate System. I would prefer to not switch to a UTM based basefile.?ÿ
Main question is, is it unheard of doing work close to state borders in a different plane system? If so, can y'all help point me to the rule? (I did a quick look and didn't see anything related)
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Thanks in advance?ÿ
Sounds reasonable to me. If there is any rule about it, it's entirely bureaucratic, not practical.
The distortion does not instantly get huge when you cross a political line. It just keeps gradually increasing as you go further. Converting is more likely to cause problems than extending a mile or three past the nominal edge.
Check the CF and convergence angle in a few places to get a feel for it.
It's not a written rule, more of what's not written. They dont say you have to stick to the state's coordinate system, you have to be clear on which you're using.?ÿ
Although NM mentions something about NM Coordinates for easements: "shows the coordinates of the beginning, ending and all angle points in accordance with the New Mexico coordinate system and shows the grid bearing and ground distance between said points;" That part is only optional though
I agree with Bill93 that it's not practical
There's nothing wrong with creating a custom projection for the project if either of the state plane zones would cause issues with distortion or convergence. If the geodetic basis is NSRS it makes it a breeze to transform to SPCS if someone really needs to.
I doubt that NM or TX statutes explicitly forbid use of anything but SPCS. Here in WA SPCS is the "official" system, but we are not constrained to it as long as we document the parameters of the system we are using. Done it many times without a problem.
Splitting a project into different coordinate systems, in my experience, runs a much higher risk of a screwup than making everything consistent across the project.
The person signing and resolving boundary is licensed in both states.
The signing person in direct personal supervision should be making those decisions. If I were required to use SPCS anywhere I'd have to correct 49 years of work. Regardless of boundaries, one project coordinate system is the answer.?ÿ
Been crossing state lines with state plane for a long time, usually pick the zone that works best for your project, I would think it's the Texas Zone since most of the work is in Texas. I can't see doing a match coordinate line, that's not fun to deal with for anyone.?ÿ
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I've had a couple projects like this along the Vermont/NY border.?ÿ As Moe said, we just picked which zone seemed to work best, discussed it with the client, and went with it.?ÿ?ÿ No problems.
That said, what's your issue with UTM?
@norm of course he's the final judge. He's just not on this forum so I am asking as proxy.
Thanks for all the replies. I'm going to pose the options to him and get this resolved.?ÿ
With due respect, it's concerning that a licensed person would need to ask or have someone ask for them.?ÿ
I regularly do surveys on tracts that are on both sides of the Tennessee-Kentucky line.?ÿ I always pick one coordinate system for the entire project.
I believe that the nomenclature contributes to the reluctance here. Would anybody be concerned about extending a project done in Projection Zone 3601 into southern Washington State? I think not. But many would recoil from using Oregon North Zone.
@norm?ÿ
Eh, I know of a couple LS's who only have ever done boundary surveys, and have never dealt with SPC.?ÿ It ain't always about the math
Boundary survey is never about math but that wasn't the question. If the licensee isn't competent in SPC they should not be involved.?ÿ
If the licensee isn't competent in SPC they should not be involved.?ÿ
Or they should let another licensee handle that aspect of it.
Nothing wrong with that, although I personally am wary of a surveyor who consciously decides to be ignorant of SPCS. It really takes some effort, because there are literally hundreds of resources, books, videos, seminars, and conferences that explain SPCS in great detail. It's been around forever.
But it seems like for every "mathemagician" surveyor who slaps record on the ground and doesn't care about existing monuments, there's a "mOnUmENtS RooL!1!" surveyor who can solve a boundary but couldn't care less about how the physical monuments were observed.
Knowing one thing should not preclude knowing another thing...