Controlling Intermediate Corners ISPLS 2017

Transcription

1 Controlling Intermediate Corners ISPLS 2017 Instructor: Dennis J. Mouland, PLS Witness Tree Consulting, Inc., 2011, All Rights Reserved

2 Course Objectives Define CIC s for surveying purposes Familiarize with background of various CIC s Discuss evidence analysis Review use and application of CIC s Examine methods for restoration of lost CIC s

3 The textbook:

4 Define What was the normal level of control set by the GLO? Section and Quarter Section Corners These are controlling, but intermediate. Intermediate to the normal level of control But still control something Line, and most proportioning

5 Some CIC s exist due to procedure Meander Corners Closing Corners Crossing Closing Corners Subdivisional Corners set previously

6 Others due to field conditions On line Witness Corners Line Trees Witness Points

7 How do we know they exist? They must be in the official GLO/BLM record Always in the notes Sometimes also shown on the plat If they were noted, you MUST look for them If found, they MUST be used

8 Chains A pine, 36ins diam.

9 What CIC s will do to your survey LT LT 1/4 Lost 1/4 WP WP RECORD MEASURED

10 We will discuss some of the CIC s in detail:

11 Meander Corners Why set to begin with? What is a meander line? Why needed today? If found, how does it control line? Do we use it in proportions of lost corners? Do we use it to set subdivisional corners? If lost, should it be reset?

12 2009 Manual A meander corner is established at every point where a standard, township, or section line or special survey boundary intersects the OHWM of a navigable stream or other meanderable body of water. (3 173)

13 MC s

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15 Meander Corners Found? Use to re establish meander line itself Use to fix alignment at that point of section line Use to set lost corners on section line Use to proportion subdivisional corners along section line Lost? Must be re established to determine any riparian issues If there has been erosion or accretion, the original MC position must be determined AND a new MC set at the current OHWL

16 Lost ¼ Corner: Lost MC: (R) = (M) X X= (R) = (M) X X= 8.09ch

17 On line Witness Corners Why do WC s exist? What about off line WC s? New policy in the 2009 Manual which aligns with BLM internal policy Always controls the alignment Use differs between section corners and quarter section corners

18 True Story WC Sec. Cor. Private Land National Forest ¼ Cor.

19 Where Witness Corners might be a good idea!

20 WC 1/ WC /4 WC WC Record Measured Result

21 WC Section Corner WC 5.00 Brg Brk at Sec Cor WC Controlling bearing pushed through at 5.00 chains (Record) Record Result

22 Line Trees Must be called for in the notes, and cite species, diameter, and distance to the nearest link. Courts have ruled that they are monuments of the original survey, which causes an angle point in the line. Used for proportioning lost corners and subdivisional corners. See BLM 6 28.

23 40.00 M= = X Proportion for 1/ /4 ¼ LOST LT Record M=32.40 Measured S1/16 to be set X

24 Witness Points How differ from Witness Corners? Sometimes referred to as artificial line trees Utilized the same as line trees Control line and alignment for lost corners and subdivisional corners

25 Closing Corners ( ) When an original closing corner is recovered off the line closed upon and the new monument is established at the true point of intersection, the original position will control in the proportionate restoration of lost corners dependent upon the closing corner. In a like manner the positioning of sixteenth section corner(s) or lot corner(s) on the closing line, between the quarter section corner and the closing corner, will be based on the measurement to the original position of the closing corner.

26 True section corners at intersection points Proportions go to original CC positions CC CC CC N1/16ths to be set 1/4 1/4 Lost 1/4

27 Sec Cor CC Fd links north of twp. line ¼ Cor = X X=20.24 R=40.27 M= /16 th to be set MINUS 0.28 = = X X= ¼ Cor.

28 Crossing Closing Corners Closing corners in some cases have been established where a line of the survey crosses previously surveyed claim lines (section 3 74 Intersecting and Terminating Section Lines ). These corners are established after a retracement of the line intersected and monumented when administratively required. In the past, these corners have been termed crossing closing corners. ( )

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31 CCC s Will bend lines if it controls the line when created Can be used to proportion lost corners if it controls: Non rectangular corners Subdivisional corners Lost PLSS corners

32 When you find a CIC Remonument as an AP Take accessories Make the details part of your record Where on the line trees?

33 If they are lost Was it ever retraced and shown off line? Re establish by proper method (7 34) Never used by a survey? May not need to be re set MC s always should be re set CCC s usually should be re set B/B intersect WP still needed? CC s adjusted once: then treated as equal Rec. Measured

34 Remon as an AP Take accessories

35 Conclusion CIC s exist in the field You must search the record for their existence You must search for them in the field You must use them as appropriate control for the line as is, lost corners, or subdivisional corners to be set Their use is not optional They will change your survey results

36 CONTROLLING INTERMEDIATE CORNERS Witness Tree Consulting, Inc., 2011, All Rights Reserved