From the manual on lost and obliterated corners;
>"Fifth: That in a fractional section where no opposite corresponding quarter-
section corner has been or can be established, the center line must be run from the
proper quarter-section corner as nearly in a cardinal direction to the meander line,
reservation, or other boundary of such fractional section, as due parallelism with the
section boundaries will permit."
I take this to mean that you run due north-south or due east-west, unless the adjacent section line bearings are both off due cardinal the same direction in which case you would hold the bearing closest to due cardinal.
The most accepted method I know of is a weighted mean bearing of the adjacent lines actually run on the ground.
Once recovered, 'stack' the adjacent lines together by traversing the bearings and distances. Now inverse to get the 'weighted mean bearing'. That in essence is the cardinal as run in the original survey...
Aye. But if I comprehend that fifth instruction correctly, that is not the correct method. For example, assume a man-made lake covered the north quarter corners and the common quarter corner of sections 10 and 11, what would the bearings to the centers of section or lake boundary be? I say in section 10 it would be east-west and in section 11 it would be N89-58W.
From the 2009 Manual:
3-120. The law provides that where no opposite corresponding quarter-section corners have been or can be fixed, the subdivision-of-section lines shall be ascertained, by running a line from the monumented corners due north and south, or east and west, as the case may be, to the water-course, reservation line, or other external boundary of such fractional section, as represented upon the official plat.
Under this subdivision-of-section method, the law presumes the section lines actually run and marked in the survey are due north and south, or due east and west lines, but usually this is not the case. Hence, in order to carry out the spirit of the law, it will be necessary in running the center lines through fractional sections to adopt mean courses, as ascertained from opposite corresponding section lines. Where an opposite corresponding section line does not exist, or the center line is platted parallel to one section boundary, run the center line parallel to the corresponding east, south, west, or north boundary of the section, as conditions may require.
3-121. The mean and parallel courses are based upon the weighted mean bearing of the controlling section line(s), equal to the bearing of the accumulated latitudes and departures of the controlling line(s) (figure 3-46).
This subdivision-of-section method is also used when the evidence conclusively shows that the meander as well as closing or equivalent corners was actually established as terminal corners.
3-122. The basic principles outlined generally give satisfactory results except in special cases. The rules cannot be elaborated to rectify conditions that are at gross variance with the representations of the official survey record. Examples of special cases that may warrant modification of the basic subdivision-of-section methods are situations where (1) the prescribed method does not result in lines and corners that represent the conditions on the official plat; or (2) a good faith rule occupation (section 6-35) has been established in reliance on a subdivision-of- section method reasonably consistent with the controlling survey plat(s). In such cases a corresponding modified plan of subdivision of section is proper.
NEW RULES
So the new manual has incorporated the "Lost and Obliterated" manual making it obsolete?
I'm still curious to know if I am getting the "Lost and Obliterated" instruction right. If so, I too have done it wrong for years by averaging the bearings. Fortunately I can only remember two instances where resorting to the fifth rule applied, I am in the process of a new one though.
NEW RULES
I was taught to establish lost corners per the instructions applicable to the date of the survey. The new manuals do not change the way things were already done. That’s why we retain copies of old instructions and manuals.
NEW RULES
> So the new manual has incorporated the "Lost and Obliterated" manual making it obsolete?
>
No, it is not obsolete. It is enhanced and clarified by the 2009 Manual.
> I'm still curious to know if I am getting the "Lost and Obliterated" instruction right. If so, I too have done it wrong for years by averaging the bearings. Fortunately I can only remember two instances where resorting to the fifth rule applied, I am in the process of a new one though.
The methods you have used are probably just fine, even though it wasn't perfectly, technically correct. In the past, the BLM publications didn't explain or publicize their evolving methodologies very well. Possibly the most important concept in the sections I posted is:
"... or (2) a good faith rule occupation (section 6-35) has been established in reliance on a subdivision-of-section method reasonably consistent with the controlling survey plat(s). In such cases a corresponding modified plan of subdivision of section is proper."
In general, the object is to "protect the plat", thus any reasonable method which does so is probably going to be acceptable.
Go forth and sin no more. 😉
The method I described is appropriate where the Corners have not and cannot be set. Obliterated corners and lines already run is a different ball game...
Don't forget to calculate the difference in magnetic declination from the time of the original survey to today. You will be more successful in your retracement.
:good:
Already found all the corners, this is a calculation exercise.
NEW RULES
:good:
