Hi - name is Andy, and whilst not (and never will be) a professional land surveyor, I have a significant interest in it, and strong background in maths / navigation / computing (e.g. programming and Excel).
We have bought land in WA, near Oroville, on a HOA consisting of 20 acre lots. The HOA was set up in the 1990s, and the definitive boundaries etc are from PLSS Surveys in the 1990's. Ultimately my aim is to transfer the surveys, or at least the ability to for areas of interest, to KML / Google Earth. I have made fair progress so far, but areas of my poor understanding leading to obvious errors - consistent in an area, so confident that solving the errors has a prospect of success.
Rather than ask a lot of questions at once, I'll ask one area at a time with my (poor) understanding and issues I've found.
PLSS Bearings
The PLSS is WA R40N 28E Section 5 here, and the image above is the North edge (right on the Canadian border).
The N Edge survey gives a bearing of N 88 55 57 E which is 88.93250deg and 5323.60' - which is 5324.00' after Survey -> Ground distance correction on the survey [1.00007431]. Online tools give the Section as:
and in 'True Bearing' terms my maths gives the bearing (NW->NE) as 89.87566deg and 5274.92'.
The question(s) I guess come down to whether the Section corners are mathematically accurate, or where a surveyor a long time back placed the 'monuments'?
The survey states 'Basis of Bearings WA State Plane Coordinate System NAD 83 (91) 4601 WA North Zone'. Online searches give some hits, but not enough for me to understand the basis for the survey bearings. Is there a bearing correction I should apply, and if so where can I find it/work it out?
The distances are also in error. It might be the survey distance / bearings are basically not accurate enough, but the precision to which they are given seems unlikely?
I have learned of 'Closure' when applied to a closed ploygon, and for 4 sided Lots is typically giving errors of 0.01' which is of course (very) accurate.
Any basic help much appreciated - I do understand that for the prfessionals this will be noddy stuff
Thanks
Andy
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