We have a municipality we are working with that establishes two points on a site with their GPS and holds one of the Grid Coordinates, back sites the second one and then does everything with the Total Station on ground.?ÿ Since we are following their work flow for this project I need to put a note on my drawings.?ÿ There are like 20 sites along a corridor that this work flow was used for.?ÿ Would love some?ÿcomments on the note below.
- BASIS OF COORDINATES:?ÿ ALL DISTANCES SHOWN ARE GROUND MEASUREMENTS AT EACH STATION.?ÿ THIS PROJECT IS BASED ON WASHINGTON STATE PLANE SYSTEM, NAD83, NORTH ZONE, U.S. FOOT, MODIFIED TO GROUND.?ÿWE FOLLOWED THE CITY OF?ÿXXXXXX WORK FLOW OF ESTABLISHING ONE GRID COORDINATE AND GRID BEARING AT EACH STATION AND ADJUSTING TO GROUND DISTANCES AROUND THE HELD GRID COORDINATE.
This is a way that I have seen lots of surveys done and firms don't really tell you what they did on their surveys.?ÿ When you are close to grid that works, but at 2000' it shouldn't be a preferred work flow. UGH
here's what i'd do (being from a completely different surveying planet):?ÿ?ÿ
ALL DISTANCES SHOWN ARE GROUND MEASUREMENTS AT EACH STATION.?ÿ THE BASIS OF BEARINGS IS WASHINGTON STATE PLANE SYSTEM, NAD83(2011 [or whatever]), NORTH ZONE, AS STATED ON THE CITY OF XXXXXX [NAME AND/OR DATE OF MAP OR DATA RECEIVED].
If I'm holding somebody else's data, I want to include as specific a reference as possible to the source of that data. Just like a deed reference.?ÿ If it isn't of any kind of record then firm names, entity names, signatory/stamper info, and dates (of publishing, of somebody emailing it to you, whatever) are all helpful in that regard.
work flow should be one word, also I think a better word could be used than workflow.
Then again if I get a copy of a Survey and he tells what he did and why he did what he did, I do not care what wording he used.?ÿ
Give the conversion factor from grid to ground or visa versa.?ÿ I see a few power companies give the the conversion on ROW plats.?ÿ
Then again if I get a copy of a Survey and he tells what he did and why he did what he did, I do not care what wording he used.?ÿ
Amen.?ÿ Makes me think of the filed plat near a relative's property that I checked out of general interest.?ÿ Fits my measurement real well as SPC and not so well as ground distances or true azimuths.?ÿ Not a hint of that in its notes.
When I have to work with something started by another I say do.
My notes say I am working on control established by others, followed by a description of what they say they did.
The sticky part is when you know they blew it and they won't talk. Then I state what it appears they really may have done as well...
I'm not sure?ÿ you should be going from grid to ground in your situation.?ÿ There was probably a reason the City set its control on grid, for instance inclusion in a city wide GIS.?ÿ It is definitely worth chatting with them about.?ÿ It is not that hard to survey on the grid with your total station.?ÿ Most modern instruments have that capability.?ÿ If your instrument does not then it is simple to do in the office.?ÿ If you are preparing documents for recording I would state that the distances are grid and give a site combined factor for those who would like to see ground distances or just apply the factor to your measurements but leave the drawings on grid.?ÿ As others have said, I would include a note stating that your survey is based on the City's control.