Doing some topo for water engineers. 19,000 foot long 36 inch irrigation pipeline. I also need to do an easement document. Had a good day on Wednesday, left 6:30 AM returned 9:30 PM (all billable). Collected about 1000 shots in various locations from one end to the other and located 5 section monuments. Pretty hard on the old bones, could drive to most areas, had to hike in a quarter mile to one å? corner. I had tie sheets with coordinates (SPC) for 3 of the corners from the county. I missed them all by about 14 feet so it appeared to be some systematic error. Tie sheet says NAD 83 Utah Central US Survey Feet. I had 10 hours static observations at the base running an R8 and R10 Rover (this works great compared to my retired 4700's). Processed through OPUS fine so I believe I'm good. Turns out if I change the units from survey feet to international feet I'm real close with the tie sheets (within a tenth on two and just under 1 foot on another). Good reason to stick with meters as there is only one meter used in surveying. Gotta keep your feet straight!
The Engineers want UTM 12N international feet. The pipeline is 10 feet shorter this way. Geez, the grid plane is way below the Ellipsoid using UTM. I've done several projects for these engineers and UTM is how they go. Nice to have software where you can make the changes with a few clicks.
The easement will need to be near ground distance and close to real North so I'll need to do some projection there so I'm pointed about the same as the BLM which owns on the other side of the section line. This is a title document not pipeline plans. Another coordinate system needed.
Sorta weird, this is way out in the boonies and all the section monuments are in place, county or BLM aluminum caps. In my home county in the occupied valley have very little of this, original section corners. We do have plenty of proportioned in corners though, every surveyor that visits thinks they need to leave one or more. More corners than you need, to bad most are just junk.
I was watching a TBC training video. Some one asked for a function to do single and double proportioning according to BLM rules. I about went crazy. That is the last function we need or want. They ought to require some special key to even access that part of the BLM Manual, the every possible kind of evidence has been determined to not exist before you get that key. I swear, some folks are mathematically determined to make the earth flat from round. We just hatch a new generation over and over.
I take it that they're laying grid pipe and not ground pipe. Can they change the diameter of the pipe by changing the scale factor?
I'm currently staking a power line for a local power company, the coordinate system is UTM zone 13, grid coordinates. I made an attempt once to explain grid to ground when they had another surveyor stake part of the line with a total station and were surprised when the PI I set didn't match what the other surveyor did. I'm doing a 24 mile stretch now, I haven't calculated the difference since all I have to do is check grid on the data collector, but I'm sure it's a substantial amount. We are at about 7800 feet elevation.
MathTeacher, post: 421430, member: 7674 wrote: I take it that they're laying grid pipe and not ground pipe. Can they change the diameter of the pipe by changing the scale factor?
No matter how hard you try to make grid pipe go geodetic north it always rotates to grid north 🙁
