Surveying

  • November 2019
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Definition of a Surveyor A surveyor is one who has the ability to use mathematics as a means to visualize objects, measure distances, sizes, and other abstract forms. They have to work with precision and accuracy, as mistakes can be costly. Surveying is called both a science and an art. Measurements are never exact or perfect, legal principles change from case law and can be considered vague at best in many circumstances.

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A Surveyor’s Job • A surveyor shares many different roles/disciplines: –





– –



Historian - tracing deeds and ownerships to their past, determining original sizes of property, where roads and rights of way were located, etc. Archeologist - determining when buildings were constructed, ages of barbed wire and fence posts, dating monuments by materials, etc. Botanist - identifying trees called for in deeds (14” shagbark hickory or a 8” pin oak tree), If a deed in 1850 called for a 24” black oak, what would it’s diameter be in 2006? If only a stump is found – count the rings to date it. Mathematician - studying analytic geometry, statistics, and trigonometry. Artist - some maps and plats (especially the older hand drawn ones) are exquisite forms of artwork. Surveying is also known as both a science and an art form, due to some measurements and evidence not fitting together as they should. Lawyer - knowledge of Local, State and Federal laws pertaining to property (adverse possession, eminent domain, riparian rights, navigational servitude, rights of ways, etc.) 4

Types of Surveying • Geodetic –

High Precision, taking many variables into account for measurements (temperature, pressure, earth’s curvature, refraction, etc.). Used by other surveys (such as making projections, highly accurate control points, etc.)

• Topographic/Hydrographic –

Shows relief of the ground (and water) through contours and elevations.

• Construction/Engineering/Rout e –

Designing and laying out various civil/architectural projects (buildings, roads, railroads, sewers, underground mining, etc.)

• Property –

Cadastral (plane surveying), dealing with recorded deeds, plans of lots, rights of ways, easements, and other items dealing with real property.

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Surveying Techniques • Global Positioning Surveying (GPS) –

Positioning from satellites based on time, vectors and additional base station triangulation. Survey grade GPS is accurate to within 5mm (< 1/4”) AFTER least squares adjustment and network triangulation. On the fly (uncorrected) can vary from 2cm (3/4”) to 1m (3’). Mapping grade is anywhere from 1m (3’) to 30m (100’), with some increasing accuracy with post processing of points based upon control monumentation.

• Digital Theodolite/EDM –

Measuring through digital readout of horizontal circle (degrees, minutes, seconds) and distances (slope, horizontal, and vertical) through infrared. Typical accuracy of EDM is ¼”.

• Transit and Tape –

Measuring through a vernier readout of horizontal circle and using a steel chain (tape) to measure distances. 6

A surveyor cannot change or revise a property line – they would give his/her legal ‘opinion’ as to it’s location. Only a judge can move the boundary. Very similar to a lawyer who cannot give a judgment in a law case, but rather their ‘opinion’. Many times – the judge may not be very familiar with real estate and boundary law… he may split the difference of the dispute (regardless of any evidence and procedures that surveyors follow). 1 Kings 3:16–28 (King Solomon’s Decree) “And the king said, Bring me a sword. And they brought a sword before the king. And the king said, Divide the living child in two, and give half to the one, and half to the other.”

Surveying is known as the worlds second oldest profession. Listed in the Bible in various places: Joshua 18:4 “Appoint three men from each tribe. I will send them out to make a survey of the land and to write a description of it, according to the inheritance of each. Then they will return to me.” Deuteronomy 19:14 “Do not move your neighbor's boundary stone set up by your predecessors in the inheritance you receive in the land the LORD your God is giving you to possess.” Deuteronomy 27:17 "Cursed is the man who moves his neighbor's boundary stone."

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LICENSURE

All 50 states require a PLS for Cadastral work.

11 of the 50 States require a PLS for Cadastral survey work only (includes Pennsylvania). The remaining 39 States require a license for any one, parts, or all of the following: Photogrammetry, Geodesy, Topography (36 States), Mining, Subdivision Engineering, Construction, Land Planning, GIS, Hydrography, and Teaching Land Surveying. 10 states now require a PLS to oversee GIS (Alabama, California, Colorado, Indiana, Massachusetts, Minnesota, New Jersey, North Carolina, Oklahoma, and South Dakota) To obtain a professional surveyors license in Ohio (as well as some other States), a four year degree in surveying is now required. Pennsylvania is leaning towards the same, but has not enacted this into law.

In Pennsylvania, the exam for licensure is given twice a year, and is two 8 hour sessions (16 hours). Both Federal and State portions are 8 incorporated, including ethics, law, hydrology, and measurements.

Surveying Facts George Washington, Abraham Lincoln, and Thomas Jefferson were all land surveyors.

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Examples, Maps, and Diagrams

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Precision is a measure of repeatability while accuracy refers to how close the average value is to the ‘true’ value.

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Ellipsoid, Geoid, and Orthometric Heights H = Orthometric Height (NAVD 88) h = Ellipsoidal Height (NAD 83) N = Geoid Height (GEOID 03)

H =h-N

h A

Ellipsoid GRS80

Geoid

H

TOPOGRAPHIC SURFACE

N

GEOID03

B

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Trigonometry/Geometry Guyasuta Survey KNOWN: Point #10 (PK)

Slope Distance: 293.93’, Zenith Angle: 72° 37’ 35”

861.58’ Elevation

Horizontal Distance = SD * sine (ZA) Vertical Difference = SD * cosine (ZA)

Point #2 (PK) 774.36’ Elevation Using trig, you get 87.77’ difference, but need to account for the difference in the height of instrument and height of rod (-0.55’)

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Guyasuta Traverse: Closure Error: 0.26’ (3 inches) Total Distance Traveled: 3,085.08’ Precision = distance/error ??Answer??

1:11,866

Third Order=1:10,000 Second Order=1:50,000 First Order=1:100,000

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The pin is no where close to where the property line should be!!!!???

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KNOWN: Horizontal Distance: 100’, Zenith Angle: 75° 00’ 00” Vertical Difference = HD * cosine (ZA) 25.9’

75 degrees 5’

100’ 5’

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KNOWN: Length of tree shadow, your shadow length, your height your shadow/your height 3/5=0.6

41.7’

Your shadow is 0.6 times your height Take tree shadow length/0.6 = ?

3’

25 ’

5’

17

5’

40’

5’

20’

1’ 5’

House to be located

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5’

40’

5’

20’

1’ 5’

House to be located

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113.83 '

120.00'

0'27" E

'00" E

°50'0

115.9

3'

S 09°07

N

36 °5

5'2

2"

E

'01" W 322.00'

16

5. 82

8" E

N 09°5

S 75

'

S 81°00

.00' " E 106

'12 N 81°35

L10

L9

L3

N 77°

13'00

"W 2 31.0

0'

0' S 86°52'00" W 194.0

L4

L8

L7

L5 L6

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113.83 '

120.00'

0'27" E

'00" E

°50'0

115.9

3'

S 09°07

N

36 °5

5'2

2"

E

'01" W 322.00'

16

5. 82

8" E

N 09°5

S 75

'

S 81°00

.00' " E 106

'12 N 81°35

L10

L9

L3

N 77°

13'00

"W 2 31.0

0'

0' S 86°52'00" W 194.0

L4

L8

L7

L5 L6

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Trail located – 46 and 32’ off

3 points shot on pavilion… all good PDOP. Why one 127’ away? (Note elevation of 1059 compared with others adjacent at 850-889’)

Boy Scouts Camp Guyasuta 23 (Trimble GeoXT) – Typ. 3’ accuracy

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Majority of input data has been ‘rubbersheeted’ (stretched in either x, y, or both to fit all errors) – losing it’s integrity. Especially deeds and parcels. Unless metadata kept up – most points have no accuracy… they may be field surveyed accurately, spotted on (guessed), or done with a GPS with 10m accuracy. Ali Al Salem example (one survey grade GPS receiver with no base station for differential corrections – all of base buildings off by 0-30’)

Aviano example (no checks into base control monuments, no idea of accuracy, movement of base station with no ones knowledge – import it all into GIS for a nice looking (but very inaccurate) map.

Tyndall example (given coordinates to stake where a berm is to be constructed.

When first turned PLGR on – it gave me coordinates, distance and bearing – but the accuracy was >1 mile! After letting it gather almanac and more satellites, was able to navigate to the approximate area (where they were already working)). 25

Choosing the wrong projection can make a HUGE difference in location (Note California or Maine) 26

Using two different Datums:

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Road*

75’

Post in Road Tax Maps and GIS layers show the mathematical polygon of the deed description as recorded. The original survey may have been paced or even guessed, but the calls to monuments (stone, tree, road, etc.) hold.

150’

Stone Monument * Call in deed just for “road” – does it mean centerline, edge of road pavement, or edge of right of way?

12” Cherry Tree

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Road

150’

Stone Monument

75’

Post not found (you were expecting to find one?)

202’ measured

36” Cherry Stump with Iron Pin placed in center

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Edge of Pavement 75’

Centerline of Road

202’ Surveyed (150’ by deed)

Edge of Pavement

Stone Monument (FOUND)

How would this affect a GIS map if it was input as 75’ x 150’ as the errant deed called for? Original Deed Line (in error)

52’ was added to the ‘depth’ of the parcel from a survey.

36” Cherry Stump with Iron Pin placed in center (FOUND) 30

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90º 90º



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0º/360º

90º 270º

180º

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What would the Bearing be of this line? The Azimuth?

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Bearing: Due South (or South 0° East, or South 0° West) Azimuth: 180 degrees

How many feet in a mile?

5,280 feet

How many square feet in an acre?

43,560 square feet

How many feet in a rod/perch?

16.5 feet

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Lots 1 and 2 are adjacent to each other – but the common line between the two have different bearings (45° and 55°) – so they are different lines?

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Lots 1 and 2 common corner on the road moved to coincide with each other – note the gap – and also the call for a 24” Oak tree – which should be the same corner.

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Lot 2 is rotated to fit Lot 1 common line (as the subject survey parcel is lot #1). Note there is no gap, and the 24” Oak is common to both lots and shown correctly.

Can anyone answer WHY the common lines would have two separate/different bearings?

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15’ error Errant Deed Plotted

Call for Pin (FOUND)

Call for Pin (FOUND)

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Two Deeds Plotted with Iron Pins (called for) held at different deed corners

Adjacent Deed (parcel to the east) – also errant.

15’ error Note overlap between two adjacent deeds. Both have errors – so field evidence would hold. Errant Deed line

Call for Pin by deed and found location 46

Surveyed Field Evidence Brand new wire fencing installed – new fence posts (following errant deed line)

Existing, ancient fence (old posts and wire fencing – some grown into older trees)

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N 12

Surveyed line follows existing, original evidence, which does not correspond exactly as either deed (but generally).

"W 0 4 ' °50

89 352 .

'

Property Line Calculated from Field Evidence

30'

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Deleted Scenes • • • • •

Pennsylvania Law Legal Description of Pennsylvania from King George Delaware’s Boundary Dispute with Pennsylvania Corradene Survey Quandary (Deed overlay/Title) What is NOT a surveyor?

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Pennsylvania Law: 1.2 Statutory Definition of Land Surveying According to the Registration Law, Section 2. Definitions "Practice of Land Surveying" means the practice of that branch of the profession of engineering which involves the location, relocation, establishment, reestablishment or retracement of any property line or boundary of any parcel of land or any road right-of-way, easement or alignment; the use of principles of land surveying, determination of the position of any monument or reference point which marks a property line boundary, or corner setting, resetting or replacing any such monument or individual point including the writing of deed descriptions; managing or conducting as managers, proprietors or agent any place of business from which land surveying work is solicited, performed or practiced; . . . (p.2) "Professional Land Surveyor" means an individual licensed and registered under the laws of this Commonwealth to engage in the practice of land surveying. A professional land surveyor may perform engineering land surveys but may not practice any other branch of engineering. (p.3) "Engineering Land Surveys" means surveys for: (i) the development of any tract of land including the incidental design of related improvements, such as line and grade extension of roads, sewers and grading but not requiring independent engineering judgment: Provided, however, That tract perimeter surveys shall be the function of the Professional Land Surveyor; (ii) the determination of the configuration or contour of the earth’s surface, or the position of fixed objects thereon or related thereto by means of measuring lines and angles and applying the principles of mathematics, photogrammetry or other measurement method; (iii) geodetic survey, underground survey and hydrographic survey; (iv) storm water management surveys and sedimentation and erosion control surveys; (v) the determination of the quantities of materials; (vi) tests for water percolation in soils; and (vii) the preparation of plans and specifications and estimates of proposed work and attendant costs as described in this section. (p.3) 51

See also the “Licensure” slide further on.

Legal Description excerpt from King George to William Penn In consideration thereof, of Our Speciale grace, certaine Knowledge, and meere Motion have Given and Granted, and by this Our present Charter, for Us, Our Heires and Successors, doe give and Grant unto the said William Penn, his Heires and Assignes, all that Tract or Parte of Land in America, with all the Islands therein conteyned, as the same is bounded on the East by Delaware River, from twelve miles distance Northwards of New Castle Towne unto the three and fortieth degree of Northerne Latitude, if the said River doeth extende so farre Northwards; But if the said River shall not extend soe farre Northward, then by the said River soe farr as it doth extend; and from the head of the said River, the Easterne Bounds are to bee determined by a Meridian Line, to bee drawne from the head of the said River, unto the said three and fortieth Degree. The said Lands to extend westwards five degrees in longitude, to bee computed from the said Easterne Bounds; and the said Iands to bee bounded on the North by the beginning of the three and fortieth degree of Northern Latitude, and on the South by a Circle drawne at twelve miles distance from New Castle Northward and Westward unto the beginning of the fortieth degree of Northern Latitude, and then by a streight Line Westward to the Limit of Longitude above-mentioned. 52

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Corradene Parcel Red=Deed Blue=Survey of 1960 Green=Tax Map

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Corradene Parcel Chain of Title (Deeds) 1910 to Present

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What is NOT a Surveyor (but may be using the tools of the trade) Anyone measuring with a GPS, tape/chain, or Theodolite/Transit. – State Police (accident reconstruction) – Related Technical Professionals (Archaeologists, Biologists, Engineers, Geologists, etc…….. They may use the tools of the surveying trade, but may not know how to validate, verify and balance if necessary, and properly convey the data. – Anyone can be taught to turn an angle and shoot a distance, or write down coordinates. Many times I have asked those using GPS, “What is the accuracy of the locations?”, and 99% of the users do not know. They don’t record PDOP’s (or even know what that means), and do not know the accuracy of the equipment. Most say the coordinate readout is to 8 decimal places – so it HAS to be accurate. 56

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