• Free 1 year academic license
  • Download from the Autodesk Student Engineering & Design Community (http://students.autodesk.com)
  • email
  • Tech Support
    • For support questions try sending an email to studentcommunity@autodesk.com
    • AutoCAD Civil 3D 2010 Installation and Licensing Training - YouTube video
  • Student Community Downloader
    • Autodesk Education Community Downloader

• based on Nadcon, Vertcon and GeoidXX (Geoid99/Geoid03)
• Download Corpscon Version 6.0.1 Complete Distribution from UNLV ( corpscon_complete.exe)
• Corpscon6_user_guide.pdf
• input format: degrees-minutes-decimal seconds (115-30-15.9)

Microsoft Excel

• Split text among columns by using functions

Special Characters

• Degree Symbol, ° = char(176)
• Single Quote, ' = char(39)
• Double Quote, " = char(34)
• Delta, Δ = delta, δ = char(68)

Named Cell, Named Range of Cells

• How do you reference named cells in a calculation? Just type in the variable/named cell name, no special characters are needed.
• 
• GraphCosine.xlsx

UNLV Library

• UNLV Library - Course Reserves - have 4 copies of the Surveying and Layout DVD on reserve
• Visit the Media Lab to gain access to an 11x17 scanner
• UNLV Library Media Lab
  • Dan Werra, Media Lab Supervisor. Email: dan.werra@unlv.edu, Voice: 702-895-2128

Jobs/Employment

• Indeed.com - one search for all jobs
• Nevada Job Connect
• Nevada Career Information System (NCIS)
  • to login, select your city (Las Vegas), Zipcode (89154) and phone area code (702)
  • click the Occupations link, search for Civil Engineering or Surveying. Then click the Outlook link on the right
  • alternatively, click on the NV Workforce Informer to see the job outlook
  • Darragh Huggins, Economist with the Department of Employment, Training and Rehabilitation - Research and Analysis Bureau. Voice: 775-684-0378, email: d-huggins@nvdetr.org
    • she sends out a yearly questionaire to 3000 employers to forecast the job demand
    • NCIS General Flyer 2010
• Tahoe Resources Inc a mining company, Cindy Saunders - Human Resources Manager (CSaunders@tahoeresourcesinc.com voice: 775-825-8574 x221)
  • Engineering Technician

Top Careers

• 2010 - 5. Environmental Engineer, 6. Civil Engineer (see CNN Money - Best Jobs in America)
• O*NET Online - Summary Report for 17-2051.00 Civil Engineers
• Bureau of Labor Statistics - Occupational Outlook Handbook - Engineers

Scholarships

• 2010 SolarNV Scholarship Application - American Solar Energy Society, Southern Nevada Chapter
• Nevada Contractors Association - David Papadopulo Memorial Scholarship application, $3750 and need to apply in the Dean's office. Due Friday 16 July 2010.

License and Certification

Fundamentals of Engineering (FE) Exam (formerly called the Engineer in Training - EIT)

Surveying Topics on FE Exam

• NCEES - Civil FE exam specifications or download FE Supplied-Reference Handbook
• Civil Afternoon Session of Fundamentals of Engineering (FE) Exam
  • distances, angles and trigonometry
  • Area computations
  • Closure
  • Coordinate systems (e.g., GPS, state plane)
  • Level (e.g., differential, elevations, percent grades)
  • Earthwork and volume computations
  • Curves (vertical and horizontal)
• approximately 11% of the test content is surveying questions
• FE sample questions
  • L:\Jeffery Jensen\CEE121\SurveyingTopicsFEExamReview2012Fall.docx or download SurveyingTopicsFEExamReview2012Fall.docx
  • FEExam-Survey.docx

California PE Exam - Surveying

• California Board of Professional Engineers and Land Surveyors
• Special Civil Engineering Examination - Engineering Surveying Test Plan

FE Review To Do

1. Earthworks - more problems, calculate cross-sectional area
2. Trig - need problems on simple areas
3. Horizontal curves - need problems

FE Survey Review and Practice Problems

1. Distances
   1. Given: Measurement of 1372.13 ft at temperature of 13°F. Find the measured distance adjusted for the correction. (Schaum's Outlines - Introductory Surveying, by James R. Wirshing and Roy H. Wirshing, Problem 3.11, p. 58)
      • see lecture notes on Steel Tape Temperature Corrections
      • corrected distance = 1372.13' + 0.00000645(13° - 68°)1372.13'
      • Solution: 1371.64 ft
   2. Given: Measurement of 697.13 ft at temperature of 72°F. Find the corrected measurement at this temperature. (Schaum's Outlines - Introductory Surveying, by James R. Wirshing and Roy H. Wirshing, Problem 3.12, p. 58)
      • see lecture notes on Steel Tape Temperature Corrections
      • corrected distance = 697.13' + 0.00000645(72° - 68°)697.13'
      • Solution: 697.15 ft
   3. Pythagoren Theorem and Rectangular Coordinates
      1. Given the coordinates of two points, Point A (125,25) and Point B (155,65), determine the length of the between them.
2. Angles
   1. convert an Azimuth of 123°17' to Bearings. (Answer: S56°43'E)
   2. convert a Bearing of S37°43'W to Azimuths. (Answer: 217°43')
      • see lecture notes on Angles - Azimuths and Angles - Bearings
   3. Add the following angles A) 100°45'37" B) 231°23'43" C) 17°12'59" D) 89°03'28" E) 101°34'24". (Answer: 540°0'11")
      • see lecture notes on Adding Angles
   4. convert Decimal Degrees (DD) to Degrees Minutes Seconds (DMS) given an angle of 236.345°. (Answer: 236°20'42")
   5. convert DMS to DD given an angle of 236°20'42". (Answer: 236.345°)
      • see lecture notes on Angle Conversions
   6. What is the sum, Σ of the interior angles for a 5 sided polygon?
      • see lecture notes on Angles of a Polygon
   7. What is the angular error/misclosure for the following angles in a 5 sided closed traverse polygon: A) 100°45'37" B) 231°23'43" C) 17°12'59" D) 89°03'28" E) 101°34'24". (Answer: 11")
      • see lecture notes on Closed Traverse Misclosure
3. Trigonometry
   1. Law of Sines
   2. Law of Cosines
      • Given a triangle with a=45.0, b=67.0, and angle C=145°, solve for side c and angles A and B. (Answers: c=107.0, A=14°, B=21°) (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanzafama, & Kissam, Example 3-15, p. 48)
      • see lecture notes on Law of Cosines
   3. Similar Triangles
      • Find the height of the tree
        
   4. Find the height of the structure
      • 
      • see lecture notes - height of objects
   5. If a map scale is 1:50,000, what does a 1-in length represent in terms of miles? What does a 1-cm length represent in terms of kilometers? (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanzafama, & Kissam, Problem 4, p. 224)
      • Answer: 1 in = 0.789 mi; 1 cm = 0.5 km
      • see lecture notes on Drawing Scales
4. Area computations
   1. Area of Triangle
   2. Area of a Trapezoid
   3. Area of a Polygon/Closed Traverse
      • Find the area of this polygon/closed traverse
        
5. Leveling
   1. 
6. Closure, Positional Certainty
   1. see lecture notes on Positional Certainty
   2. 
7. Earthwork Calculations
   1. 
   2. Given just black portion of the above figure in the problem description. The volume of the embankment per 100-ft length is most nearly equal to? (Civil Engineering Problems and Solutions , 14th Ed, Donald G. Newnan, p. 12-26 and 13-31)
      1. 5000 ft³
      2. 8250 ft³
      3. 52,000 ft³
      4. 82,500 ft³ (correct answer)
      5. 102,800 ft³
   3. see Average End Area Formula
8. Horizontal Curves
9. Vertical Curves

Fundamentals of Surveying (FS) Exam (formerly called the Land Surveyor Intern - LSI)

• 8 hr exam administered by NSCEE
• NV Land Surveyor Intern (LSI) Application Instructions
  • Land Surveyor Intern Experience Summary
• FS Sample Questions and Solutions Book
• FS Reference Formulas
• Education in Surveying: Fundamentals of the Surveying Exam by Robert J. Schultz, PE, PLS. Professional Surveyor Magazine, March 2006 Volume 26 Issue 3.
• 15 Major Topics, 170 Questions
  1. Algebra and Trigonometry - 11%
  2. Higher Math (beyond trigonometry) - 4%
  3. Probability and Statistics, Measurement Analysis, Data Adjustment - 5%
  4. Basic Sciences - 4%
  5. Geodesy, Survey Astronomy, and Geodetic Survey Calculation - 6%
  6. Computer Operations and Programming - 6%
  7. Written Communication - 6%
  8. Boundary Law, Cadastral Law and Administration - 13%
  9. Business Law, Management, Economics, Finance, and Survey Planning Process and Procedures. - 6%
  10. Field Data Acquisition and Reduction - 10%
  11. Photo/Image Data Acquistion and Reduction - 4%
  12. Graphic Communication, Mapping - 6%
  13. Plane Surveying Calculation - 10%
  14. Geographic Information System (GIS) Concepts - 4%
  15. Land Development Principles - 5%

Nevada Revised Statues - Professional Engineers and Land Surveyors

• NRS 625.270 Qualifications of applicant for licensure as professional land surveyor. [Effective July 1, 2010.]
• NRS 625.280
  • 3. The Board may administer or authorize an accredited college or university that offers a program in land surveying approved by the Board to administer the examination on the fundamentals of land surveying to persons who are not applicants for licensure as professional land surveyors in this state.
  • Emailed James Elithorp with Great Basin College (GBC) to see if he administers this test to his students at GBC on 19 June 2010
• NRS 625.386 Qualifications for certification as land surveyor intern or engineer intern.
  • 1. To be eligible for certification as a land surveyor intern, an applicant must:
    (a) Be a graduate of or in the final year of a land-surveying or engineering curriculum of 4 years or more that has been approved by the Board and have passed the examination on the fundamentals of land surveying provided for in NRS 625.280;
    
    or
    
    (b) Have had 4 years or more of experience in land-surveying work that is satisfactory to the Board and have passed the examination on the fundamentals of land surveying provided for in NRS 625.280.

State Board of Engineers and Land Surveyors

1. Alaska
2. Arizona
3. California
4. Colorado
5. Florida
6. Hawaii
7. Maine
8. Massachusetts
9. Minnesota
10. Nevada
11. New Mexico
12. New York
13. Oregon
14. Texas
15. Utah
16. Washington
17. Wisconsin

Surveying Certification

• National Society of Professional Surveyors (NSPS) Certified Survey Technician (CST) - 2009 CST Program Test Prep

Autodesk Academic Certification

• Two levels of Certification: 1) AutoCAD Civil 3D 2010 Certified Associate (student cost is $25) see autodesk.starttest.com and 2) AutoCAD Civil 3D 2010 Certified Professional (student cost is $50)
• Web-delivered exams requiring the students to demonstrate their skills by using Autodesk applications such as AutoCAD, Autodesk Inventor Professional, Revit Architecture and AutoCAD Civil 3D software products to solve real-world problems.
• www.autodesk.com/academiccertification
• Testing center email: certification@autodesk.com

Global Positioning System (GPS) Technology Certificate

• University of California, Riverside (UCR). UCR Extension Center on 1200 University Ave.
• Jennifer Campbell, Program Coordinator (voice: 951-827-1620, email: sciences@ucx.ucr.edu)
• No Federal Financial Aid is available
• ERT X440.1 - Principles of GPS Technology
• ERT X440.2 - Fundamentals of Geodesy
• ERT X440.3 - GPS Techniques: RTK, CORS and DGPS by Derek Main. Jan 30 (Mon 6-9pm) Feb 4 (Sat 8-5pm) Feb 13 (Mon 6-9pm) Feb 25 (Sat 8-5pm) Feb 27 (Mon 6-9pm) Mar 5 (Mon 6-9pm) Mon 6-9pm on Jan 30, Feb 13, Feb 27 and Mar 5, then Sat 8-5pm on Feb 4 and Feb 25
• ERT X440.4 - Control Surveys Using GPS by Arthur R. Andrew III, PLS for County of Orange. Sept 11-12, 2010
• ERT X440.5 - GPS Leveling by Jay Satalich, PLS for Landata Airborne Systems, Inc
• ERT X440.6 - Survey Data Adjustments
• ERT X440.8 - GPS Processing and Analysis
• ERT X440.9 - Map Projections by Kevin Kelly is a Geodetic Engineer with ESRI Redlands. Jan 21-22, 2012 cost is $345 Oct 23-24, 2010
• ERT X453.6 - GIS Data Capture Using GPS Technology by Warren Roberts (email: wroberts@riohondo.edu or gisteacher@gmail.com) GIS Coordinator with Rio Hondo College, Whittier CA.

Surveying and GIS

List of Professional Organizations

American Society for Photogrammetry and Remote Sensing

• Membership for those interested in the practice of photogrammetry, remote sensing, and/or geographic information systems and related sciences. Active ($135), Associate ($90) and Student ($45). Includes 12 issues of PE&RS
• ASPRS Student Advisory Council
  • Meghan MacLean (meghan.maclean@unh.edu) is the Student Advisory Chair and Rose Kearney (jmerose@gmail.com) is the former chair.
  • ASPRS Southwest Region Student Chapter - Creating_New_ASPRS_Student_Chapter.pdf
  • Will have a national chapter contest in Fall 2010, contact Rose Kearney for more info.
• Paul R. Wolf Memorial Scholarship

National Society of Professional Surveyors (NSPS)

Nevada Association of Land Surveyors

• Trent Keenan, PLS, President-Elect of NALS Southern Nevada Chapter. Diamondback Land Surveying, 4933 W Craig Rd, Las Vegas NV 89130 phone: 702-596-3257 email: tkeenan@diamondbacklandsurveying.com
• Terry W. McHenry, PLS, Editor, The Nevada Traverse
  14710 Rancheros Dr
  Reno NV 89521
  email: editornvtraverse@sbcglobal.net
  Bus/Fax: 775-852-7290
• Linda Armstrong, Executive Secretary, email: larmstrong@nv-landsurveyors.org
  NALS Central Office
  PO box 20522
  Reno NV 89515
  Bus/Fax: 775-624-6257
  ask about questions regarding student memberships

California Land Surveyors Association

• Scouting Merit Badge

American Congress on Surveying & Mapping (ACSM)

• Student Chapter Info
• The American Congress on Surveying and Mapping
  6 Montgomery Village Avenue, Suite 403
  Gaithersburg, MD 20879
  Phone (240) 632-9716 Fax (240) 632-1321
  
• Membership contact email: trisha.milburn@acsm.net voice: 240-632-9716 x105. Cost is $28 a year, gives membership to ACSM, NSPS, GLIS and ASPRS
• Can purchase the 2009 Manual of Surveying Instructions. Cost $125, if order 24 copies can get a 20% discount. If order 48 copies can get a 40% discount. Can also order other textbooks can get a 20% discount.
• Scholarships
  • $5000 for those who compete in the Tri-Star high school event

Geographic and Land Information Society

• GIS for Surveying - GLIS Annual GIS Competition contact ilse.genoveseo@acsm.net

Student Activities

• ASCE Student Chapter
  • Pacific Southwest Regional Conference (PSWRC) 2010
  • Survey Competition - Team Leader asce.unlv@gmail.com
  • Spring 2010 ASCE Survey Team: Alexander Wood (wood.alexander@rocketmail.com), Glenn Blake (gblake@unlv.nevada.edu), Alex Teran (ax.te@hotmail.com)

Surveying Colleges and Universities

• California State University, Fresno - Department of Civil and Geomatics Engineering and Construction Management - Geomatics Engineering Program

Class Roster

2010 Spring Semester - Instructor Jeff Jensen

Student Family Name, First Name	Preferred Email	Picture
Bernales, Lawrence	bernales@unlv.nevada.edu
Campuzano, Jesus	jesus_campuzano747@yahoo.com
Carlson, Matt	mcarlson91@gmail.com
Carral, Hugo	corral.hugo@yahoo.com
Dushane, Tanner	tdushane24@hotmail.com
Feige, Roxanne	feiger@unlv.nevada.edu
Fields, Jason	fieldsj8@unlv.nevada.edu
Gebilaguin, Adrian	gebilagu@unlv.nevada.edu
Hoese, Alexander	a11hoese@aol.com
Hernandez, Allison	herna613@unlv.nevada.edu
Hiko, Aly	cytotox1c@yahoo.com
Kazarin, Robert	robert_kazarin@yahoo.com
Lopez, Luky	rlpurplerose@gmail.com
Mejia, Dimaz	dimasmejia16@yahoo.com
Pfabe, Pisani "Blaise"	blaisepisani90@gmail.com
Pamintuan, Rommel	pnoyrcp@msn.com
Reynoso, Ryan	Ryonnn@gmail.com
Sadeh, Hooman	sadeh@unlv.nevada.edu
Sanchez, Alfredo	sanch430@unlv.nevada.edu
Shkrobat, Maryna	SHKROBAT@UNLV.NEVADA.EDU
Smiecinski, Peter	Sk8terx010@aol.com
Vallejos, Ricardo	vallej10@unlv.nevada.edu
Vincent, Brian	brianvinc@hotmail.com
Webber, Conor	conorwebber@mac.com
Winton, Reece	wintonr@unlv.nevada.edu
Wong, Nicolas	nwong1991@gmail.com

2010 Spring Semester - Instructor Jeff Jensen

Student Family Name, First Name	Preferred Email	Picture
Agpawa, Leo	leoagpawa@gmail.com
Almosawy, Jaffer	j.almosawy@live.com
Ayala, Johanan "Isaac"	ayala702@yahoo.com
Cisneros, Christian	cisner34@unlv.nevada.edu
Corniel, Darryl	cornield@unlv.nevada.edu
Cretty, Janegela "Jane"	crettyj@unlv.nevada.edu
Filter, Elizabeth "Liz"	littlelizf89@aim.com
Franco-Rivas, Humberto "Bert"	wario2060@hotmail.com
Goerl, Ryan	ryangoerl@gmail.com
Kaur, Gurtarpreet	gurtar_kaur@yahoo.com
Leon, Joseph	kxrider18@aim.com
Naccarato, Blake	blake.naccarato@gmail.com
Natale, Nicholas	hatnick@aol.com
Palmer, Joshua	jjpalmer81@gmail.com
Pascua, Juan	pascuaj@unlv.nevada.edu
Radke, Brittany	radkeb4@unlv.nevada.edu
Torio, Evander	TORIOE@UNLV.NEVADA.EDU
Villarosa, Manuel "Manny"	mmvillarosa@hotmail.com

2010 Spring Semester - Instructor Jeff Jensen

Student Family Name, First Name	Preferred Email	Picture
Alan, Milad	alanm2@unlv.nevada.edu
Avery, William	whythefxcknot@aol.com
Blake, Glenn	gblake@unlv.nevada.edu
Buzzone, Brooklyn	buzzone2@unlv.nevada.edu buzzoneb@gmail.com
Cretty, Janegela "Jane"	crettyj@scsv.nevada.edu
Daughenbaugh, John	daughenb@unlv.nevada.edu
Demarco, Jake	demarcoid@yahoo.com
Gebremichael, Negasi	hiyab29082008@yahoo.com
Groneman, Kurt	gronema4@unlv.nevada.edu ksgroneman@msn.com
Heraypur, Aria	aria_heraypur@hotmail.com
Holcomb, Ronald	rholcomb3@gmail.com
Inos, Vincent	vinceinos@gmail.com
Laramore, Edith	elaramore@gmail.com
Mclean, Adam	mcleana5@unlv.nevada.edu
Mora, Edgar	morae@unlv.nevada.edu
Murphy, Mary	murphy12@unlv.nevada.edu
Perez, Geraldine	g.joannaperez@hotmail.com
Pollock, Scott	pollock.scottj@gmail.com
Rocha, Jonathan	rochaj3@unlv.nevada.edu
Sacundo, Erwin	sacundo2@unlv.nevada.edu
Serrano, Alexy	marias18642@earthlink.net
Shrestha, Shailendra "Shale"	shresth6@unlv.nevada.edu
Teran, Emanuel "Alex"	ax.te@hotmail.com
Underwood, Nicholas	underw44@unlv.nevada.edu
Vazquez, Pablo	vazque63@unlv.nevada.edu vazlop90@gmail.com

Surveying Parties/Groups

1. Nicholas, Luky, Reese, Rommel, Peter
2. Brian, Alex, Tanner, Jason, Roxanne
3. Carlson, Pisani, Adrian, Jesus, Hugo
4. Ricardo, Allison, Maryna, Robert, Aly
5. Dimas, Ryan, Lawrence, Alfredo, Conor, Hooman

Web Grading and Roster

• Grades are always due on the Tuesday following the last final exam by 4:00pm. Please check with your units, as they may have set an earlier due date than the Registrar's Office
• Final grades submitted online at WEB GRADING/CLASS ROSTERS
• Username: jjensen
• L-Number/PIDN: L000577789
• any problems, contact Ruth.Garay@unlv.edu, voice 702-895-3372 or Jim, voice 702-895-0892
• College of Engineering Email: http://mail.egr.unlv.edu
  • Use if username@egr.unlv.edu
• UNLV Email: http://rebelmail.unlv.edu
  • Use if username@unlv.nevada.edu

Web Campus Support

• Call the OIT Help Desk at 702-895-0777 and use option 2 for Web Campus
• Courses should automatically be the first day of class but can request them to be added sooner, send an email to ithelp@unlv.edu and use a subject "adding a course onto web campus account"
• How do I add a teaching assistant to the web campus account?
• How do I use a login besides my L# (L000577789) and normal-web?

College of Southern Nevada (CSN) Web Grading

• Final grades submitted online at CSN Web Grading
• Username: Jeffery.Jensen
• Password: normalwebsite1
• C#: C000136261
• Employee ID: 000074476
• CSN Webmail: webmail.csn.edu
• CSN email: jeffery.jensen@csn.edu and voice: 702-651-4947 (Bob Diaz)
• FERPA Online Training completed on 12/15/2011
• Autodesk Training Videos
  • csn.cadlearning.com
  • login: jeffery.jensen@unlv.edu and password: normalweb

CSN VPN Account

• https://access.csn.edu
• H:\ Drive, need to map a network drive to \\otscyfs01.csn.edu\users\jeffery.jensen
• J:\ Drive, need to map a network drive to \\otscyfs01.csn.edu\users\departments
• login: CSN\jeffery.jensen
• password: normalweb

Survey Equipment

• UNLV Surveying Contacts
  • Allen Sampson - sampson@ce.unlv.edu is the supervisor over the College of Civil Engineering survey equipment
• GPS
  • UNLV Facilities Management
    • Ken Hughes, Construction Project Coordinator II (friend of Vern Little) voice: 895-5480, mobile: 301-1938, email: ken.hughes@unlv.edu
    • Tad McDowell, Director of Parking & Transportation Services, voice: 703-895-5531, email: tad.mcdowell@unlv.edu
  • Proposed - R8 GPS Receiver Model 1, 3 units of Trimble M3 Total Stations and 1 TSC2 Survey Controller
    • $19000 (PO-UNLV-Monsen-R8-M3-TSC2-05072010.pdf)
    • add 4 tape measures in decimal feet
    • ensure M3 comes with poles and prisms
    • add a barometer for Sokkia SET6, I think the M3 already have a built in barometer
  • Approved - Trimble R8 GNSS Rover, TSC2 Controller and misc equipment
    • $9400 ( PO-UNLV-Monsen-R8_GNSS.pdf
      PO-UNLV-Monsen-R8_GNSS_04162010.pdf
      Picked up the equipment 16 July 2010 from Bill at Monsen Engineering PackingSlip-UNLV-Monsen-R8_GNSS.pdf)
  • Trimble R8 GNSS
    • Trimble R8 GNSS Receiver User Guide
    • Front Panel
      • 
      • 
  • Trimble R8 GPS (Model 1)
    • Datasheet (TrimbleR8Datasheet.pdf)
    • User's Guide: R8GNSS-R6-5800_364_UserGuide.pdf
    • Serial Number: 4451142125
    • UNLV Purchase Order (PO#21002616)
    • This R8 GPS unit is better than the Trimble 5800 but not as good as the R8 GNSS (support the Russian GLONASS satellites)
    • Signals: L1, L2, L2C (L2 Civil Signal)
      • GPS Signal Frequencies (obtain from the front inside cover of Elementary Surveying, 12th Edition by Ghilani and Wolf)

        Code	Frequency (MHz)
        C/A	1.023
        P	10.23
        L1	1575.42
        L2	1227.60
        L5	1176.45

    • 
    • Online Positioning User Service ( OPUS) antenna type: TRM_R8
  • Trimble TSC2 Controller
    • Serial Number: SS08A03023
    • UNLV Purchase Order (PO#21002615)
    • Version: 12.45 build: 077
    • Authorization key: 7A8T-OXCX-3F4T-HOBO
    • Software Warranty Expiry: 12/2010
    • Trimble Survey Controller (TSC2) Support
    • User's Guide: TSCv1246_Help_English.pdf (from UNLV) or TSCv1246_Help_English.pdf (from Trimble)
    • Datasheet (download TrimbleTSC2Datasheet.pdf from UNLV)
    • 
    • Notes
      • Trimble Data must be stored under My Device -> Trimble Data and can only have one level below Trimble Data. All Map data must be in the same folder as the Job.
      • Map Files
        • graphic representation of features - points, lines, arcs (ESRI shapefiles .shp or AutoCAD (ASCII) .dxf), alignments/Trimble roads (.rxl), digital terrain models (.dtm .ttm). These must all be stored in the current project folder to access.
        • It appears aerial photos are not supported
        • Trimble Survey Controller (TSC) Help -> Job Operations -> Map of Current Job and Active Map
        • Questions
          • What is the benefit of using a Map File?
          • How does TSC handle the projection information for a shapefile?
          • Can Civil 3D Surface be exported into a .dtm or .ttm format and displayed in TSC?
    • Great Basin College
      • Trimble provided several Relectorless Total Stations with the necessary accessories to outfit two survey crews. The Nevada Association of Land Surveyors had monies in their "National Society of Professional Surveyors" equipment fund to purchase the equipment for the college at a very nominal fee.
      • Dr. James Elithorp, Land Survey/Geomatics Program Coordinator, voice: 775-753-2240, email: jamese@gwmail.gbcnv.edu
  • Software
    • soti.net Pocket Controller Pro V6. Questions contact sales@soti.net download trial copy of SOTI Pocket Controller-Pro or from here Pocket Controller-Pro V6.02 24 Mar 2009
      (L:\Jeffery Jensen\downloads\trimble.com\soti.net\PCPro602Setup.exe)
    • Trimble Business Center 2.20 (Nero ISO DVD image L:\Jeffery Jensen\downloads\trimble.com\TrimbleBusinessCenter2-20.nrg)
    • TSC version 12.42 Emulator ( L:\Jeffery Jensen\downloads\trimble.com\TSCv1242_Installation_Emulator.exe)
    • Microsoft ActiveSync 4.5 download for Windows XP
      (L:\Jeffery Jensen\downloads\trimble.com\ActiveSync4.5\setup.msi)
      • Click cancel on the Pocket PC Sync dialog box when connecting the TSC2 to the desktop computer using Microsoft ActiveSync.
      • 
    • Windows Mobile Device Center for Windows 7
• Automatic Levels
  • 5 automatic levels
    • Pentax AL-M2c, Serial Numbers: 821402, 821406, 821407, 821409, and 821410.
    • 
    • 
• Tribrachs and Tribrach Adapters
  • Monsen Engineering Supply tribrach adjustment invoice (MonsenInvoiceTribrachAdjust.pdf)
• Level Rods
  • 3 Philadephia Rods
  • 3 Fiberglass Telescoping Leveling Rods, CR-13-T, Crain Enterprises, Inc Mound City, IL. On 10 Jan 2008 Trimble Navigation Ltd purchased Crain Enterprises Inc (see Trimble buys Crain Enterprises)
  • 
• Tripods
  • 4 - Pentax Tripods
  • 2 - Ingenuity Inc Tripods
  • 1 - Wild GST20 Tripod
  • Invoice for Tripod leather straps, 3 fiberglass telescoping leveling rods, single job field books, tribrack adapter and a prism. (PO-UNLV-Monsen-Tripods.pdf)
  • 
• Electronic Level
  • Spectra-Physics EL-1. Serial Number 19136. Manufactured April 1987. Model 1044.
• Prisms
  • Omni Prisms - Optical Products, Inc. Phone: 949-833-3388
  • Wild GPH1A snap on prism
    • 
    • 
  • • "Once known, the electrical center of the EDM can be shifted forward to compensate for the reflector constant. However, if an EDM instrument is being regularly used with several unmatched reflectors, this shift is impractical. In this instance, the offset for each reflector should be substracted from the observed distances to obtain corrected values." (Elementary Surveying, 12th Edition by Charles D. Ghilani and Paul R. Wolf, p. 158-9)
    • Figure 6.16 Schematic of retroreflector where D is the depth of the prism
    • 
• Total Stations
  • Sokkia SET6, Serial Number: D20833
    • 
    • Invoice for Battery Charger, RS232 to 9-pin cable and tripod TSC2 holder (PO-UNLV-Monsen-Set6-Battery.pdf)
    • SokkiaSet6F-TotalStation.pdf obtained from Scribd - Sokkia SET 6F Total Station Brochure
    • Sokkia technical support, email: support@sokkiacorp.com or support@topconsokkia.com
    • SokkiaSET6-Manual.pdf
    • Data Collector
      • Set6 has an RS-232C data output connector. Using a cable with a 9-pin connection, the Set6 can be connected to a Trimble TSC2 data collector
    • SET6 Parts
      • 
  • SET6 Instrument Parameters
    • 
  • Error Codes
    • b. dEd is displayed, the battery voltage is too low for measurement. Turn the power switch off and re-charge the battery. (This display also occurs during measurement when the battery power is low.) Sokkia SET6 Operator's Manual, p. 13
    • V 0 display indicates that the instrument is ready for vertical circle indexing. Sokkia SET6 Operator's Manual, p. 13
      • 
      • Indexing the vertical circle - Loosen the vertical clamp and rotate/flop the telescope to break the horizontal plane or can just completely rotate the telescope around 360° in the vertical. Indexing occurs when the objective lens crosses the horizontal plane in face left. The audio tone sounds and the vertical angle (V) is displayed.
      • Angle measurement can now begin. The instrument is now in the theodolite mode. Each time the instrument is switched on, the vertical index must be redetermined. Sokkia SET6 Operator's Manual, p. 15
      • 
    • E 114, E 115, E 116 or E 117 is displayed when the tilt angle exceeds 10'. Re-level the SET6 using the plate level bubble. Sokkia SET6 Operator's Manual, p. 13
    • Battery Power - when the SET6 power switch is ON and after successful completion of the checks, the batter power is displayed as a numeric code for three seconds.
      • 

        Error Code	Battery Life Remaining in (Angle only mode)	Battery Life Remaining in (Distance and Angle mode)
        bA 0	Less than 1 hr 20 min	Less than 30 min
        bA 1	1 hr 20 min to 11 hrs 50 min	30 min to 2 hrs 30 min
        bA 2	11 hrs 50 min to 20 hrs 50 min	2 hrs 30 min to 2 hrs 50 min
        bA 3	20 hrs 50 min to 21 hrs 40 min	2 hrs 50 min

        
        
    • E 201 is displayed, the return signal is absent. In this situation, sight the prism correctly and remeasure. Sokkia SET6 Operator's Manual, p. 28
• Theodolites
  • Pentax FX-1DE, Serial Numbers: 810868, 810857, 810808 (missing a case), 810774 and 810816
  • Instruction Manual
  • 
  • Horizontal angles, smallest reading is 20" (20 seconds)
  • Purpose of Lower Tangent Screw and Lower Clamp Screw
    • Used by the telescope cross-hairs to sight a point
    • With the lower clamp screw loose, can roughly turn the theodolite onto a point and line up with the gun sight/collimator/peep sight.
    • With the lower clamp screw tighten, can finely tune the telescope cross-hairs onto a point
  • Purpose of Upper Tangent Screw and Upper Clamp Screw
    • Used to zero out the theodolite when looking into the angle reading eyepiece. Also need to use the micrometer/micro knob to zero out the minutes and seconds in the angle display.

Survey Control by TRC

• $2400 to update and expand the existing survey control on UNLV campus by Scott Hill, PLS with TRC
  • Revised and condensed into a single Purchase Order
    • PO-UNLV-TRC-DeliverableAll.pdf
  • Original Purchase Orders
    • Deliverable 1 - Procurement of UNLV Survey Markers for Record of Survey, $750 due 6/1/2010 PO-UNLV-TRC-Deliverable1-Procurement.pdf
    • Deliverable 2 - Record of Survey to be filed with the Clark County Recorder's Office, $850 due 6/1/2010 PO-UNLV-TRC-Deliverable2-RecordSurvey.pdf
    • Deliverable 3 - Land Surveying Field Courses, $450 due 6/1/2010 PO-UNLV-TRC-Deliverable3-FieldCourses.pdf
    • Deliverable 4 - Existing Survey Control Inventory, $350 due 6/1/2010 PO-UNLV-TRC-Deliverable4-SurveyControl.pdf

Guest Speakers

• Scott Hill, TRC Solutions. Mobile: 702-208-4766, Work: 702-248-6415, email: shill@trcsolutions.com, address: 1009 Whitney Ranch Dr, Henderson NV 89014
• Trent Keenan. Mobile: 702-596-3257
• Jan Van Sickle (GPS & GNSS for Geospatial Professionals video modules)

Instructor To Do List

• Where is the NAVD88 datum in relationship to the topographic surface of the earth, the geoid and the WGS84 ellipsoid?
• Where is the NAD83 datum when moving positions from Lat/Long to ellipsoid to the Stateplane Grid?
• Lab Module Template
  • Purpose or goal of the module, for example why are we teaching engineering students on how to use a theodolite?
  • Student Outcomes - what do we want the student to know when they are done
  • Procedures - for example steps to setting up a tripod
  • Example Practice Problems
  • Homework questions that support the lab topics
  • Test to verify students obtain the desired outcome.
  • Reading Materials - references to the textbook and DVD videos to enhance knowledge on the lab topic
  • Time Frame - how many lectures and/or labs needed for the student to learn the materials
• Create Lab Modules for the following topics
  • FE exam - survey questions (March 1, 2010)
    • Add question references
    • Add similar questions from textbook used by Tom Barnes (Schaum's Outline of Introductory Surveying)
  • Setup a tripod (March 7, 2010)
  • Using a Theodolite (March 14, 2010) - how to zero out the instrument, turn single and double angles, record measurements in the field book, how to calculate average measurement and adjust errors
  • How to use the Chain/Steel Tape to measure distances
  • Plumb Bob
  • GPS
  • Total Station
  • Automatic Level - include benchmark books from the cities and counties
  • Rotational Level
  • Importing points to create a surface and topo map
  • CAD - drafting from the field book notes and measurements
  • Research Record of Surveys from the County Recorder's Office (can get from their website).
  • Horizontal and Vertical Curves - how to layout
• Class Advisors - Ed Neumann and Barbara Luke (email: barbara.luke@unlv.edu voice: 702-895-1568)
• How to create a Civil 3D Field Book file (.fbk) from Trimble GPS or a total station instrument?

Surveying Topics on Exams

• NCEES - Civil FE exam specifications
• Civil Afternoon Session of Fundamentals of Engineering (FE) Exam
  • Angles, distances and trigonometry
  • Area computations
  • Closure
  • Coordinate systems (e.g., GPS, state plane)
  • Curves (vertical and horizontal)
  • Earthwork and volume computations
  • Level (e.g., differential, elevations, percent grades)
• approximately 11% of the test content is surveying questions
• FE sample questions - FEExam-Survey.docx

California PE Exam - Surveying

• California Board of Professional Engineers and Land Surveyors
• Special Civil Engineering Examination - Engineering Surveying Test Plan

Grading

Lecture Homework

Email Rules when submitting answers to homework assignments

• Email answers to class email address (formerly cee301spring08@gmail.com, cee301@egr.unlv.edu, cee301fall07@gmail.com )
• Email subject Line must contain Week number and name. Example Week 5 - John Doe
• Typically must attach a JPEG image, PDF or DWF of homework assignment. Each email must include all the .jpg images for that weeks assignment. For example if your Week 3 home is to do Module 3 and it has 4 exercises, I want one email with 4 attachments instead of 4 emails with one attachment each.
• Always use the same email account when submitting homework. Don't send email assignment from UNLV email account one week, next from a work email account, and then another time using a personal email account. Use one account only when corresponding with the Instructor.
• Item to email will identified below with the heading Email

Lecture Homework

1. Lecture Homework #1 (assigned week 1)
   • bring headphones/earphones if you want to watch Survey & Layout DVD in class
   • CEE121HW01-Worksheet.doc - Angle conversion and reading a ruler
   • Obtain UNLV Computer Account to login to computers in TBE-B367 and A311 labs. Example UNLV email (e.g. username@egr.unlv.edu or username@unlv.nevada.edu)
   • Create an Autodesk Community Student account at http://students.autodesk.com
     • email
   • Know how to Transfer files between home/work and UNLV. Recommend using SSH, NetStorage, USB Thumbdrive, email or burning a CD
   • Download and Install Autodesk Civil 3D at home/work from http://students.autodesk.com
   • Email send an email from your preferred email account to class email address Subject line must be as stated in the Email Rules above.
   • Email a thumbnail picture of yourself
   • Email members of your group, no more than 3 students per group
2. Lecture Homework #2 (assigned week 1)
   • Webcampus: Tripod setup rule of thumb, determine the following 1) length of your foot/shoe 2) TripodX distance from lecture notes on Instrument Setup 3) InstrumentY height for the Total Station, 4) InstrumentY height for the Theodolite, 5) InstrumentY height for the Automatic Level, 6) rule of thumb, what body part is used to measure the height of a closed tripod (e.g. chin, shoulder, chest) to ensure a proper tripod setup?
3. Lecture Homework #3 (assigned week 2)
   • Practice setting up a tripod in the field
   • Webcampus: measure your pace distance. See class notes on Pacing
4. Lecture Homework #4 (assigned week 3)
   • Webcampus: upload a scanned copy of your field notes which contain the following:
     • Pick a minimum of 2 UNLV Survey points/monuments/benchmarks per person in your surveying party/group/crew. So if your group has 3 people, need a minimum of 2 x 3 = 6 points
     • Determine the approximate distance between the selected points using your pacing skills.
     • Hand draw a sketch on a landscape 8.5"x11" piece of paper. Reference the class lecture on proper field notes. Mainly, the right side of the page will have the field sketch and the left side of the page will have the pace measurements (i.e. tabulations).
5. Lecture Homework #5 (assigned week 3)
   • Solve for the distance AB from the example triangle shown on the website (TrianglesSimilarExample) when distance ab = 638, distance bC = 903 and distance BC = 1732. See lecture notes on similar triangles
   • Using the automatic levels, determine the horizontal (stadia) distance of the same points measured in the previous homework using a steel tape/chain and pacing.
     • Upload a scanned a copy of your field notes and sketch.
     • see lecture/class notes on how to Measure Horizontal Distances using the Stadia method from an automatic level.
6. Lecture Homework #6 (assigned week 3)
   • Webcampus: a scanned copy of your field notes from the in class assignment: with the survey field book/paper passed out in class, copy the level circuit/loop recordings from the textbook (see Chapter 5, p. 108 and class notes on Leveling). Note, you do not have to show the adjusted elevation calculations. Remember the UNLV Library has scanners.
   • Email the solution to these problems on level loop field notes and reading a level rod - Level Field Notes from 1001 Solved Surveying Fundamentals Problems, 2nd Edition by Jan Van Sickle, PLS. ISBN-13 978-1-888577-12-9 Provide the values for U, V, W, X, Y and Z in the email.
   • Perform one of the following level circuits which are located just south of the UNLV TBE building. Record measurements in your field book. Add a sketch of the site. Show a north arrow. Provide names of the group members. Have the Notekeeper (N) sign the bottom right corner of the field notes. Make a photo copy of your groups Field Notes for the given Level Loop and turn in by next Saturday.
     • Map of survey points on UNLV campus
     • Check your assigned Loop# under Surveying Parties/Groups
   • Check the following instruction Using calculators
   • Email the solution to these problems (conversion between DMS and DD)
     • CEE121HW04-Worksheet.docx - dms calculations
   • Email a scanned copy of your field book (.pdf or .jpg) showing your closed traverse using a theodolite and chain/steel tape. This is just your raw field notes before you do the Compass Rule traverse adjustment.
   • Balancing Angles - using your field notebook and textbook, recreate the Figure 10.1 sketch and calculate the adjustment of angles (Table 10.1). Use the class notes on Traverse - Balancing/Adjustment of Angles for the procedure. Email a scanned pdf or jpg image of your field notebook page.
   • Email pdf of textbook closed traverse. Using AutoCAD Civil 3D and the class notes from CEE 301 - Drafting a Traverse recreate Figure 10.1 sketch from the textbook. Plot to a PDF using 8.5"x11" papersize and a viewport scale of 1"=200'. Label the bearing and distance of each line. Include your name, date and week# on the plot.
   • Email scanned copy of Azimuth angles. Determine the Azimuth for each segment in the textbook (Figure 10.1 and Example 10.2 for Table 10.2). Draw a hand sketch of each point (A,B,C,D,E) showing the North Meridian line, the backsight point, the foresight point, and reference angle arrows.
   • Email Excel spreadsheet of the Compass Rule used to adjust your UNLV loop (1, 2, 3, 4, or 5)
   • Email a scanned copy of your field book showing the Compass Rule adjustment done by hand.
   • Email a scanned copy of your field book showing the differential leveling on your UNLV loop (1, 2, 3, 4, or 5). Also include a copy of the stadia distances.
   • Adjust the distances using the compass rule in the Textbook, Figure 10.1 page 240. Calculate the coordinate values for each point (A,B,C,D,E). Can submit a print out from Excel if used to calculate the coordinates (northing and eastings).
7. Lecture Homework #7 (assigned week 10)
   • Email a scanned copy of your field book showing the differential leveling to determine the Finish Floor Elevation of Artemus Ham Concert Hall (HCH)
     • 
8. Lecture Homework #8 (assigned week 5)
   • Email the area from Problem 12.22 in Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 321
     • The (X,Y) coordinates (in feet) for a closed-polygon traverse ABCDEFA follow. A (1000.00, 1000.00), B (1661.73, 1002.89), C (1798.56, 1603.51), D (1289.82, 1623.69), E (1221.89, 1304.24) and F (1048.75, 1301.40). Calculate the area of the traverse by the method of coordinates.
   • Email an Excel spreadsheet. Use Excel to solve Problem 12.22 above. See class notes on Area of a Closed Traverse - Coordinate Method
   • Email a screen shot AutoCAD image of Problem 12.22 above. Draw the closed-polygon traverse using the POLYLINE (PLINE) command. Determine the area by selecting the properties of the traverse.
   • should look similar to this
   • 
   • ElemSurvey12th-Prob12_22.dwg
9. Lecture Homework #9
   • Field Exercise: Total Station Topo (TopoSummer2010.vce)
   • Email the answers from Steve Youngberg's Lecture on Public Land Survey System (PLSS) (Chapter 22 from textbook)
     1. What is the name of the initial point that Nevada surveys are based on?
        • Mount Charleston Base and Meridian
        • Tahoe Peak Base and Meridian
        • Mount Diablo Base and Meridian
        • Gila and Salt River Base and Meridian
     2. Charleston Boulevard is the south line of Township 20 South and is a standard parallel. Which parallel is it?
        • Forth Standard Parallel South
        • Fifth Standard Parallel South
        • Eighth Standard Parallel South
        • Tenth Standard Parallel South
     3. How many miles south from the Initial Point is it (Charleston Blvd)?
        • 96
        • 120
        • 150
        • 240
     4. What section is directly south of section 23?
        • 22
        • 24
        • 25
        • 26
     5. What are the numbers of sections which usually have irregular areas in a typical Township?
        • 1-6 and 7-12
        • 1-7, 18,19,30 and 31
        • 1,12,13,24,25, and 31-36
        • 1-6 and 31-36
     6. What are the dimensions of the sides, in feet, of a parcel described as the SE 1/4, NW 1/4, Section 14?
        • 660’x660’
        • 1000’x1000’
        • 1320’x1320’
        • 2640’x2640’
     7. A father gave his son the S 3/4 of the SE 1/4 of a regular 1/4 section. What is the area of the parcel?
        • 30 acres
        • 40 acres
        • 120 acres
        • 160 acres
10. Lecture Homework #10
    • Email a pdf map created in AutoCAD Civil 3D to the UNLV campus topographic drawing created by AeroTech in 2007 ().
11. Lecture Homework #11
    • Email a pdf map created in Google Earth Pro of the State Plane Coordinate Zones from the usstpln83.shp. Add a placemark showing the origin of the Nevada East Zone (without applying a false northing and easting). It should look similar to this.
    • 
12. Lecture Homework #12
    • Email a legal description written from the following figure:
    • 
    • HWLegalDescription.dwg
    • HWLegalDescription.pdf
    • Use the legal description from Clark County Assessor Plat Book 94 Page 86 as an example. HWLegal-PlatBook94Page86.pdf
    • See chapter 21 in the textbook and class notes on Writing Legal Descriptions
13. Lecture Homework #13
    • For the following circular curves having a radius R, what is their degree of curvature by (1) arc definition and (2) chord definition? Given answers in Degrees, Minutes and Seconds
      1. 300.00 ft (answer D_a = 19°05'55" and D_c = 19°11'17")
      2. 1500.00 ft (answer D_a = 3°49'11" and D_c = 3°49'14")
      3. 4000.00 ft (answer D_a = 1°25'57" and D_c = 1°25'58")
      • Elementary Surveying, 12th Edition, by Ghilani and Wolf, p. 741
      • see notes on Degree of Circular Curve
14. Lecture Homework #14
    • Email a screenshot of the Civil 3D TIN surface and contours created from TOPO survey done with Bill from Monsen Engineering UNLVTopoLabNAD27-June2010-rotate.txt
    • Email a screenshot of all the NGS monuments near UNLV. See notes on NGS Data Sheets

Final Exam

Send answers to the class email by Friday, 7 May 2010 at 10:00am

1. A differential leveling loop began and closed on BM Tree (elevation 323.48 ft). The plus sight and minus sight distances were kept approximately equal. Readings (in feet) listed in the order taken are 3.18 (BS) on BM Tree, 4.76 (FS) and 2.44 (BS) on TP1, 3.05 (FS) and 6.63 (BS) on BM X, 3.64 (FS) and 2.35 (BS) on TP2, and 3.07 (FS) on BM Tree. Prepare, check, and adjust the notes.
   1. What is the misclosure? A) 0.02 ft B) 0.08 ft C) 8 feet D) 0
   2. How many instrument setups were done? A) 1 setup B) 4 setups C) 8 setups D) 0 setups
   3. What is the correction per setup (ratio of misclosure/number of instrument setups)? A) 0.02 ft B) -0.002 ft C) -0.2 ft D) 2 ft
   • Elementary Surveying, 12 Edition by Ghilani and Wolf. Chapter 5 - Leveling - Field Procedures and Computations, problem 5.11
   • Class Notes - Leveling
2. Create field notes and a sketch from the data in Elementary Surveying, 12 Edition by Ghilani and Wolf. Chapter 10 - Traverse Computations, problem 10.6 and 10.7
   • Create the sketch using AutoCAD Civil 3D. Dimension the unadjusted interior angles. Plot to PDF or make a screenshot image of the drawing. Attach this to your email when submitting the answers.
   • Class Notes - Traverse Field Notes
3. Balance the following interior angles (angles-to-the-right) of a five-sided closed polygon traverse using method 1 of Section 10.2 If the azimuth of side AB is fixed at 48°31'43", calculate the azimuths of the remaining sides. A = 41°09'44", B = 200°52'14", C = 124°57'26", D = 64°28'16", E = 108°32'10", (note: Line BC bears NE)
   1. What is the misclosure? A) 9" B) 10" C) 11" or D) 12"
   2. What is the adjusted angle for D? A) 64°28'16" B) 64°28'18" C) 108°32'12" D) 64°28'20"
   • Notes
   • Elementary Surveying, 12 Edition by Ghilani and Wolf. Chapter 10 - Traverse Computations, Problem 10.6
   • Class Notes - Traverse - Balancing/Adjustment of Angles
   • Remember, once you have adjusted the interior angles, the starting and end point still will not match. Need to do the compass (Bowditch) rule to adjust the lengths.
     • 
4. Compute departures and latitudes, linear misclosure, and relative precision for the traverse of Problem 10.6 if the lengths of the sides (in feet) are as follows: AB = 150.50, BC = 610.39, CD = 485.14, DE = 735.35, and EA = 647.34 (Note: assume units of feet for all distances)
   1. What is the sum of lengths? A) 2601.27 ft B) 2628.72 ft 2601.72 ft C) 2600.27 ft or D) 2600.72 ft (answer was off by 27 ft, correct answer is B = 2628.72 ft)
   2. What is the sum of departures? A) 0.03 ft B) 0.019 ft C) -0.042 ft or D) 0.046 ft (remember if the departure value is positive then you need to substract your correction in departure)
   3. What is the sum of latitudes? A) 0.042 ft B) -0.042 ft C) 0.024 ft or D) -0.24 ft (remember if the latitude value is negative then you need to add your correction in latitudes) then you need to substract your correction in departure)
   4. What is the Linear Misclosure? A) 0.03 ft B) 0.046 ft C) 0.064 ft or D) 0
   5. What is the Relative Precision? A) 1:57146 1:10000 B) 1:60000 1:56000 C) 1:57100 1:65000 or D) 1:57000 1:100000 (calculated relative precision is 1:57146 but needs to be rounded to what precision?)
   • Elementary Surveying, 12 Edition by Ghilani and Wolf. Chapter 10 - Traverse Computations, Problem 10.7
   • Class Notes - Traverse - Compass (Bowditch) Rule and
     Traverse - Compass (Bowditch) Rule: Relative Precision
5. Using the compass (Bowditch) rule, adjust the departures and latitudes of the traverse in Problem 10.7. If the coordinates of station A are Eastings (X) = 20,000 ft and Northings (Y) = 15,000 ft calculate coordinates for the other stations and then the lengths and azimuths of lines AD and EB.
   1. Length of AD? A) 1000 ft B) 1123.58 ft C) 2311.58 ft or D) 543.14 ft
   2. Azimuth AD? A) 30° B) 45°42'14" C) 45°14'43" or D) 176°51'29"
   3. Length of EB? A) 1000 ft B) 543.14 ft C) 453.14 ft or D) 1123.58 ft
   4. Azimuth EB? A) 45°42'14" B) 176°51'29" C) 376°51'29" D) 124°57'28" (hint: Bearing EB is S 3°08'31" E)
6. You are working on neighborhood preservation project to rebuild an antiquated school, moderize it like the more sophisticated A-Tech High School. Please find the closest NGS Datasheet in the Valley to the intersection of Eastern and Karen. Note, this NGS survey control point must exist, that is the LAST_COND cannot be DESTROYED or MARK NOT FOUND. Also, for safety reason, please don't try to visit the sight in attempts to find the monument/benchmark :-)
   1. What is the Permanent IDentifier (PID) station name? A) AC3363, B) GR1312, C) GR1954, D) 2653
   2. What is the NAVD 88 elevation in feet at this point? A) 556.318, B) 1825.12, C) 1852.91, D) 2012
   • Class Notes: NGS Data Sheet
   • Tip: to import an ESRI Shapefile into Google Earth Pro, use File -> Import... then change the file type to ESRI Shape (*.shp).

Introduction to Surveying

1. Definition of Surveying
2. Math Review
   • Trigonometry Review
   • Area of a Triangle

Definition of Surveying

• Field Measurements
• "Surveying, which is also interchangeably called geomatics, has traditionally been defined as the science, art, and technology of determining the relative positions of points above, on, or beneath the Earth's surface, or of establishing such points. In a more general sense, however, surveying (geomatics) can be regarded as that discipline which encompasses all methods for measuring and collecting information about the physical earth and our environment, processing that information, and disseminating a variety of resulting products to a wide range of clients." (Elementary Surveying, 12th Edition by Charles D. Ghilani and Paul R. Wolf, p. 1)
• Geodetic Surveys
  • "In geodetic surveying, the curved surface of the Earth is considered by performing the computations on an ellipsoid (curved surface approximating the size and shape of the Earth)" (Elementary Surveying, 12th Edition by Charles D. Ghilani and Paul R. Wolf, p. 7)
• Plane Surveys
  • "In plane surveying, except for leveling, the reference base for fieldwork and computations is assumed to be a flat horizontal surface. The direction of a plumb line (and thus gravity) is considered parallel throughout the survey region, and all observed angles are presumed to be plane angles. For areas of limited size, the surface of our vast ellipsoid is actually nearly flat. On a line 5 mi long, the ellipsoidal arc and chord lengths differ by only about 0.02 ft." (Elementary Surveying, 12th Edition by Charles D. Ghilani and Paul R. Wolf, p. 9)

Trigonometry and Coordinate Geometry Review

Oblique Triangle

• 
• A° + B° + C° = 180° (for a triangle on a flat plane)

Law of Sines

Law of Cosines

• a² = b² + c² - 2bc cos A
• b² = a² + c² - 2ac cos B
• c² = a² + b² - 2ab cos C

Area of a Triangle

• How to calculate the area of an oblique triangle (triangle that does not contain a right angle)
• 
• 

Area of a Parallelogram

Area of a Trapezoid

• 
• Math Open Reference - Area of a Trapezoid
• Math Open Reference - Video: Area of a trapezoid - derivation of the formula

Area of a Closed Traverse - Coordinate Method

• "When the coordinates of the stations of a closed traverse are known, it is a simple matter to computer the area within the traverse, either by computer or handheld calculator." (Surveying Principles and Applications, 8th Edition by Barry Kavanagh, p. 215)
• 
• Math Open Reference - Area of a Polygon (Coordinate Geometry)
• "Because of the effects of error propagation, it is important to remember that it is better to be conservative when expressing areas, and thus a phrase such as '6.258 acres more or less' is often adopted, especially when writing property descriptions." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 309)
• Area by Coordinates: "The areas of trapezoids are, in effect, being summed with appropriate algebraic signs. The result of the computation is double the area, which must be divided by 2." (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanzafama, and Kissam. p. 157-8)
• "State simply, the double area of a closed traverse is the algebraic sum of each X coordinate multiplied by the difference between the Y coordinates of the adjacent stations. The double area is divided by 2 to determine the final area. This rule applies to a traverse with any number of sides. The final area can result in a positive or negative number, reflecting only the direction of computation (clockwise or counterclockwise). The physical area is, of course, positive; there is no such thing as a negative area." (Surveying Principles and Applications, 8th Edition by Barry Kavanagh, p. 215)
• Area by Coordinates formula
  • n = number of vertices in the polygon
  • x_ny_n = x₀y₀ where the first and last vertices are the same
  • vertices must be ordered clockwise (negative area) or counterclockwise (postive area)
  • 
  • 
  • "The subscript n stands for the total number of stations in the traverse. The coordinates for the first station are repeated at the end of the sequence, but it really does not matter which is considered the first station..." (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanzafama, and Kissam. p. 157-8)

Similar Triangles

• Requirement: all angles are the same, so in the case of a pair of triangles, all three pairs of corresponding angles are the same, AAA (angle angle angle).
• 
• 
• Example Problems
  • 
  • Civil 3D 2010 drawing - TrianglesSimilarProblem.dwg and TrianglesSimilarProblemSolution.png

Sigificant Figures

• "In recording observations, an indication of the accuracy attained is the number of digits (significant figures) recorded. By definition, the number of significant figures in any observed value includes the positive (certain) digits plus one (only one) digit that is estimated or rounded off, and therefore questionable. For example, a distance measured with a tape whose smallest graduations are 0.01 ft, and recorded as 73.52 ft, is said to have four significant figures; in this case the first three digits are certain, and the last is rounded off and is therefore questionable but still significant." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 27)
• "...if data are recorded with more figures than those that are significant, false precision will be implied." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 27)
• "The number of significant figures is often confused with the number of decimal places. Decimal places may have to be used to maintain the correct number of significant figures, but in themselves they do not indicate significant figures. Some examples follow:
  
    Two significant figures: 24, 2.4, 0.24, 0.0024, 0.020, 2.4 X 10³ (2400)
    Three significant figures: 364, 36.4, 0.000364, 0.0240, 2.40 X 10³ (2400)
    Four significant figures: 7621, 76.21, 0.0007621, 24.00, 2.400 X 10³ (2400)
  
  Zeros at the end of an integral value may cause difficulty because they may or may not be significant. For example, in a value expressed as 2400, it is not known how many figures are significant; there may be two, three, or four, and therefore definite rules must be followed to eliminate the ambiguity. The preferred method of eliminating this uncertainity is to express the value in terms of powers of 10. The significant figures in the measurement are then written as a number between 1 and 10, including the correct number of zeros at the end, and annexing a power of 10 places the decimal point. As an example, 2400 becomes 2.400 X (10)³ if both zeros are significant, 2.40 X (10)³ if one is, and 2.4 X (10)³ if there are only two significant figures." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 27-28)

Angles

• How to add Angles in DMS format? Recommend converting to DD, then add, and then convert back to DMS
• Convert Decimal Degrees (DD) to Degrees Minutes Seconds (DMS)
  • 236.345° = 236° + 0.345° = 236° + 0.345° (60'/1°) = 236° 20.7' = 236° 20' + 0.7'(60"/1') = 236° 20' 42"
• Convert Degrees Minutes Seconds (DMS) to Decimal Degrees (DD)
  • 236° 20' 42" = 236° + 20' (1°/60') + 42" (1'/60")(1°/60') = 236° + 0.333° + 0.012° = 236° + 0.345° = 236.345°

Microsoft Calculator

• Has the ability to convert between DD and DMS
• Must use Scientific View (Menu bar: View -> Scientific)
  • 

TSC2 Calculator

• How to open the Calculator program on the TSC2. Within Trimble Survey Controller, click Cogo and then Calculator
  • 
• Calculator Settings, click the checkbox button to set the Calculator mode into Standard or RPN (default)
  • 
• To enter angles in Degrees Minutes Seconds format, type the degrees value then click the ° ' " button. Then type in the minutes value and again click the ° ' " button. Finally type in the seconds value and click the ° ' " button.
  • 

Using calculators in degree mode

• Texas Instruments - TI-Nspire Solution 26570: Converting Degrees/Minutes/Seconds (DMS) to Decimal Format Using the TI-Nspire Family Handheld and Computer Software
• TI-36II Angle Modes
• TI-83 Angle Operations
• TI-84 Plus Angle Operations
• Examples
• Convert decimal degree to radians
  236.345° = 236.345° (π radians/180° )= 4.125 radians

Matrices

Multiply (Product) of two Matrices

• "The matrix multiplication is not commutative, the order in which matrices are multiplied is important. In fact, this little setback is a major problem in playing around with matrices. This is something that you must always be careful with." (S.O.S. Math - Multiplication of Matrices)
• 

Horizontal Curves

Types of Horizontal Curveys

• Horizontal Curves - "curves used in horizontal planes to connect two straight tangent sections" (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 703)
• Simple Curve
  • "A simple curve is a circular arc connecting two tangents (straight sections)." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 703)
• Compound Curve
  • "A compound curve is composed of two or more circular arcs of different radii tangent to each other, with their centers on the same side of the alignment.... often used on exit and entrance ramps of interstate highways and expressways, although easement [spiral] curves are generally a better choice for these situations." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 703)
• Broken-back Curve
• Reverse Curve
  • Often seen at street intersections which have a left turn lane and an island/median.
  • Used to shift the travel direction of a vehicle. For example at standard parallels, the townships and ranges are adjusted to compensate for the curvature of the earth. This causes a shift in the section lines, that is they are no longer continuous. Problem is sections lines are typically the right of way of a street. To keep the movement of vehicles flowing, a reverse curve is often used in urban design.
  • "A reverse curve consists of two circular arcs tangent to each other, with their centers on opposite sides of the alignment.... reverse curves are unsuitable for modern high-speed highway, rapid transit, and railroad traffic and should be avoided if possible." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 703)
  • example of a rural highway with a reverse curve
  • 
    View Larger Map
• Spiral Curve
• Simple, Compound, Broken-back and Reverse Curves
• 
• Compound and Reverse Curves
• 

Degree of Circular Curve

Circular Curve Formula

Instrument Setup

• When placing the instrument on the tripod, it is customary to align the base of the instrument with the head of the tripod as shown in this figure.
  • 
• With the tripod still closed, loosen the tripod thumbscrews, extend the tripod legs until it stands about shoulder height. Then slightly tighten the thumbscrews.
  • 
  • Height of SET6 Total Station (distance between base of instrument and eyepiece/scope)
    • 
  • Height of Automatic Level
    • 
  • Height of Theodolite
    • 
  • Height of Tribrach
  • How to calculate ideal tripod setup
    • Determine eye height of the surveyor/instrument man. Using a tape measure, measure the vertical distance from the ground to the surveyor's eye height. Record this value as EyeY
    • Determine the instrument height (will vary between equipment). Record this value as InstrumentY
    • Tripod height (TripodY = EyeY - InstrumentY). Determine this height on your body, maybe it is your shoulder or chest height and use this as a rule of thumb when extending the tripod legs.
    • using the Law of Sines and that the tripod metal shoes are tilted about 75°, calculate TripodX distance (TripodX = TripodY * sin15°/sin75°)
    • Measure the length of your foot and use this as a rule of thumb to identify the distance between the ground monument and the tripod metal shoe.
• For a firm and secure tripod setup, the tripod metal shoes are inserted vertically into the ground. Note the angle of the metal shoe tips is about 75° from the horizontal, see figure below.
  • 
• Make a mental note of your foresight and backsight. When setting up the tripod want to avoid straddling one of the tripod legs to make a measurement. It is easy to bump/misalign the tripod if you straddle it.
• Rotate the tripod and hold the two legs closest to you. Place the 3rd leg about 1.5'-2.0' feet beyond the ground monument point. Then pull back the other two legs and place equal-distance from the ground monument point. The top of the tripod must be directly over the ground monument point.

Tripod Setup

• Background
  • Almost impossible to setup a tripod at 1) a given height, 2) directly over a monument/point and 3) level. Typically disregard #1 and just use a tape measure to record the instrument height in the field notes. The following tripod setup procedure will address #2 and #3 requirements.

Three-Screw Leveling Head

• Paul Holley Method of Tripod and Instrument Setup
  • Only adjust 2 legs on the tripod. This will ensure the head plate of the tripod remains fixed over a point.
  • Only adjust 2 thumbscrews (A and B on figure below) on the instrument. Do not adjust the third thumbscrew C.
• Before placing the instrument on the tripod and before storing the instrument in the case, check to see the screws are indexed.
  • "On most instruments, the midpoint of the leveling screw is shown with a line on the screw body. When the top of the knob is on the line, an equal amount of rotations of the screw can be made up, and an equal amount down. Store your instrument with all leveling screws indexed." (Construction Surveying and Layout, 3rd Edition by Wesley G. Crawford, Creative Construction Publishing, Inc. p. 3-45)
• "The advantage of the three-screw leveling head system is that an instrument can be leveled more quickly. It is indeed quicker if a systematic approach to leveling the instrument is followed. Persons have been observed going around in circles trying to level this type of system because they were using it improperly." (Construction Surveying and Layout, 3rd Edition by Wesley G. Crawford, Creative Construction Publishing, Inc. p. 3-47)
• 
• 

Procedure to measure horizontal angles using a Theodolite

• 
• Step 0: setup, level the instrument and plumb over a monument/point
• Step 1: zero out the instrument
  • A. loosen the upper and lower clamp screws
  • B. rotate the black circle rotating ring until you read 0 in the graduation display cutout. Then tighten the upper clamp screw.
  • C. look in the angle reading eyepiece and rotate micro knob until you read 00 on the center right side of the field view for clockwise horizontal angles. Note the micro knob can only fine tune 60 minutes (1°).
    • "Adjust the openess and direction of the reflecting mirror for obtaining optimal brightness for circle reading." (Pentax Theodolite FX-1DE Manual, p. 21)
    • 
  • D. look in the angle reading eyepiece and turn the upper tangent screw until the horizontal graduation line is in the center of the indexing lines. Note the upper tangent screw can turn ~ 6°
    • 
  • E. the instrument should now be set to zero. Do not touch the micro knob, upper tangent screw and upper clamp screw until Step 3.
• Step 2: focus on your backsight
  • A. with the upper clamp screw tighten and the lower clamp screw loose, rotate the theodolite/instrument until the object lens is pointing at the target. Use the clear white triangle in the collimator/gun sight/peep sight to line up the instrument with the backsight. Might need to rotate the telescope if the collimator/gun sight is on the bottom.
    • 
  • B. tighten the lower clamp screw
  • C. while looking in the eyepiece, rotate the eyepiece ring until the cross hairs/reticle appears as its maximum sharpness. In otherwords focus the cross hairs using the eyepiece ring.
    • "If focusing is correct, the cross hairs will not move in relationship to the object when you move your eye slightly left and right while looking through the eyepiece. This will eliminate any parallax." (Pentax Theodolite FX-1DE Manual, p. 15)
    • 
  • D. while looking in the eyepiece, rotate the focussing knob on the telescope until the backsight becomes clear/in focus.
  • E. use the lower tangent screw to line up the vertical cross hair with the backsight. The lower tangent screw adjusts the telescope left and right.
    • If you cannot rotate the lower tangent screw any more and still not on the backsight, then rotate the lower tangent screw back about 3° and then loosen the lower clamp screw and resight on the backsight. Tighten the lower clamp screw and then again try adjusting the lower tangent screw.
  • F. (Optional) use the telescope clamp and upper tanget screw to line up the horizontal cross hair with backsight. This adjusts the telescope up and down.
  • G. look in the angle reading eyepiece to double check the angle is zero.
  • H. Double check the optical plummet is still centered on the ground mounment.
• Step 3: turn the angle
  • A. loosen the upper clamp screw. This keeps the circle rotating ring fixed.
  • B. rotate the instrument to the foresight. Line up the foresight with the collimator/gun sight/peep sight. Remember in a closed traverse it is customary to turn angles to the right, so rotate the instrument clockwise.
  • C. tighten the upper clamp screw
  • D. while looking in the eyepiece, rotate the focussing knob until the backsight becomes clear/in focus.
  • E. use the upper tangent screw to line up the vertical cross hair with the foresight. This adjusts the telescope left and right.
  • F. (Optional) use the telescope clamp screw and telescope tangent screw to line up the horizontal cross hair with the foresight. This adjusts the telescope up and down.
  • G. look in the angle reading eyepiece, rotate the micro knob until the graduation line is in the center of the indexing lines. Read outloud the clockwise angle (angle turned to the right).
    • 
  • H. record the horizontal angle in the Field Book
• Step 4: repeat the angle measurement (double angle) on backsight
  • A. flip the telescope 180°, that is flop the scope. So if the collimator/gun sight is on top of the telescope it is now on the bottom. Might need to loosen the telescope clamp screw.
  • B. loosen the lower clamp knob/screw and rotate the instrument back onto the backsight. Use the clear white triangle in the collimator/gun sight to line up the instrument with the backsight. Note the circle rotating ring will rotate with the instrument.
  • C. Tighten the lower clamp knob/screw
  • D. while looking in the eyepiece, rotate the focussing knob until the backsight becomes clear/in focus.
  • E. use the lower tangent screw to line up the vertical cross hair with the backsight. This adjusts the telescope left and right.
  • F. (Optional) use the telescope clamp and telescope tangent screw to line up the horizontal cross hair with backsight. This adjusts the telescope up and down.
  • G. look in the angle reading eyepiece to double check the clockwise angle (angle turned to the right) is still reading the same angle measurement as it was on the foresight.
• Step 5: turn the double angle to the foresight
  • A. loosen the upper clamp screw
  • B. rotate the instrument to the foresight. Line up the foresight with the collimator/gun sight. Remember in a closed traverse it is customary to turn angles to the right, so rotate the instrument clockwise.
  • C. tighten the upper clamp screw
  • D. while looking in the eyepiece, rotate the focussing knob until the backsight becomes clear/in focus.
  • E. use the upper tangent screw to line up the vertical cross hair with the foresight. This adjusts the telescope left and right.
  • F. (Optional) use the telescope clamp and telescope tanget screw to line up the horizontal cross hair with backsight. This adjusts the telescope up and down.
  • G. look in the angle reading eyepiece, rotate the micro knob until the graduation line is in the center of the indexing lines. Read outloud the clockwise angle (angle turned to the right).
    • 
  • H. record the double angle in the Field Book.
• Step 6: divide the double angle by 2. Record this as the average/mean angle between the backsight (BS) and the foresight (FS).
  • example: 77°56.8'/2 = (77 + 56.8' (1°/60'))/2 = 38°58'24"
• Step 7: relocate theodolite to next point
  • "Just before taking up the transit, center the instrument on the foot plate, roughly equalize the leveling screws, clamp the upper motion, unclamp (or clamp lightly) the lower motion, point the telescope vertically up, and clamp the telescope lightly." (Surveying Theory and Practice, 3rd Edition by Raymond Davis and Francis Foote, p. 283)

Positional Certainty

• "Positional certainty means a measurement of the relative accuracy of positions with respect to the location of a controlling monument." (NAC 625.651)
• Positional certainty: Horizontal and vertical components of certain land surveys (NAC 625.666)
  • Topographic Surveys
    • Engineering Design Surveys... ±0.03 ft to ±0.3 ft
• When submitting a Plat to Clark County, it must close within 0.01 ft according to Erik Denman, PLS (voice: 702-455-2103, edenman@co.clark.nv.us)

• "Because many existing products, including control datasheets in the NAD83 datum, refer to the 1984 standards, these will also be described. This eariler set of standards established three distinct orders of accuracy to govern traditional control surveys, given in descending order:"

Accuracy for Vertical Control Surveys

• "The relative accuracy required for a vertical control or leveling survey depends on its purpose. A set of standards and specifications has been prepared by the federal government for the national control network; this also serves as a guide for surveyors in private practice. There is a hierarchy of several different orders and classes for vertical accuracy standards. These standards are expressed in terms of an allowable error of closure, as well as relative accuracy between points." ( Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanazfama and Kissam, ISBN-13 978-0-13-500037-3, p. 100-1)
• "The allowable error of closure is a function of the length or total horizontal distance of the leveling line or circuit. The function is expressed in the following form: error = constant x √distance. The higher the order of accuracy, the smaller the constant." (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanazfama and Kissam, ISBN-13 978-0-13-500037-3, p. 100)

Accuracy for Horizontal Control Surveys

• "Relative Accuracy for horizontal distances, the ratio of the error of closure to the actual distance is called the relative accuracy. (In some other textbooks, it is also referred to as the degree of accuracy, order of accuracy, accuracy ratio, relative precision or just plain precision. No matter what it is called, the concept is essentially the same.)" (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanazfama and Kissam, ISBN-13 978-0-13-500037-3, p. 28)
• 
• "Distance measurements of very high precision, such as made with EDMIs, may be characterized in terms of parts per million (ppm) of accuracy. For example, a relative accuracy of 5 ppm is equivalent to the ratio 5:1,000,000, or 1:200,000. In a distance of, say 1 km, or 1000 m, an accuracy of 5 ppm would be caused by an error of 5 mm[i.e., 1:(1000 m/5 mm) = 1:(1,000,000 mm/5 mm) = 1:200,000]." (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanazfama and Kissam, ISBN-13 978-0-13-500037-3, p. 29)

Linear Error of Closure (LEOC)

• "The linear error of closure is the net accumulation of the random errors associated with the traverse measurements." (Surveying with Construction Applications, 7th Ed by Barry F. Kavanagh, p. 172)
• "After measuring 3739 feet, the traverse had an LEOC of 0.1131 feet. Expressed as a ratio, 1 foot in 33000 feet means that if the field crew had measured 33000 feet using the same techniques and precision, they would have been off 1 foot." (Construction Surveying and Layout, 3rd Edition by Wesley G. Crawford, Creative Construction Publishing, Inc. p. 14-24)
• "When writing the specification for a survey, it is very impractical to specify the exact degree of accuracy that is to be attained in each of the measurements. For this reason, specifications are based on the minimum degree of accuracy for the particular survey. The range between the allowed degrees of accuracy is known as an order of accuracy. The orders of accuracy for surveys are called first order, second order, third order, and lower order. The measurements for first-order surveys are the most accurate, and the measurements for the other orders are progressively less accurate." (Introductory Surveying - Schaum's Outlines by James R. Wirshing and Roy H. Wirshing. ISBN-13: 978-0-07-071124-2, p. 88)
• 

Differential Leveling - Allowable Misclosure

• 
• 1998 - National Spatial Data Infrastructure - Geospatial Positioning Accuracy Standards - Part 2: Standards for Geodetic Networks
• 1984 - Federal Geodetic Control Committee - Standards and Specifications for Geodetic Control Networks
  • 3.5 Geodetic Leveling
  • "Geodetic leveling is a measurement system comprised of elevation differences observed between nearby rods. Leveling is used to extend vertical control."
  • Office Procedures
  • 

ALTA/ACSM Land Title Surveys

• Allowable Relative Positional Accuracy for Measurements Controlling Land Boundaries on ALTA/ACSM Land Title Surveys
  • ±[0.07 feet (or 20 mm) + 50 ppm]
  • 2005 Minimum Standard Detail Requirements for ALTA/ACSM Land Title Surveys as adopted by American Land Title Association and National Society of Professional Surveyors
  • Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 636

Field Notes

Field Notes - Background

• Considered to be one of the most important aspects of a survey
• Must be recorded at the time of the survey
• Record field notes with a pencil
  • "Recording Data - A 4H pencil, well pointed, should be used. Because of its simplicity, Reinhardt's style of slope lettering (Fig. 76a) is generally conceded to be the best form of lettering for taking notes rapidly and neatly." (Surveying Theory and Practice 3rd Edition by Raymond E. Davis and Francis S. Foote, p. 45, also see 6th Edition, p. 55-6)
  • Reinhardt Lettering
    • font is very similar to romans.shx or simplex.shx AutoCAD Shape Fonts or romans.ttf or simplex.ttf True Type Fonts also from Autodesk.
    • The Technic of Mechanical Drafting by Charles W. Reinhardt (download from UNLV mechanitechnicof00reinrich.pdf)
    • 
    • Lettering for Draftsmen, Engineers and Students by Charles William Reinhardt
  • "A hard pencil- 4H or harder- should be used to prevent smearing. The notebook should be of good quality, since it is subjected to hard usage. No erasures should be made, because such notes will be under suspicion of having been altered. If an error is made, a line should be drawn through the incorrect value and the new value should be inserted above." (Surveying, 10th Edition by Francis H. Moffitt and John D. Bossler, p. 9)
• Digital photos may be attached to the field notes as supporting info
• "If corrections to the notes are necessary, a line will be drawn through the error (without obscuring it) and the correct value or information written adjacent to it. Any entries made to the field notes subsequent to the actual survey should be shown in RED." (ODOT Survey Field Note Standards p. 2)
• "Each time the instrument is set up the field note will contain a 'Setup Line'. This will include: Instrument @ Point (#), height of instrument, description of occupied point, backsight @ point (#), description of backsight point, and height of backsight target (ODOT Survey Field Note Standards p. 3)
• Oregon Dept of Transportation - Survey Field Note Standards

Field Notes - Outside Cover and Title Page

• Outside Cover
• Title Page (1st inside page)
  1. title sheet (first page) to include
     • full names of all crew members. Crew member initials can then be on the subsequent pages
     • Project name
     • Location
     • Description
     • Date
     • Equipment used
  2. Contact info of Notebook Owner
     • "Letter the notebook owner's name and address on the cover and first inside page using permanent ink. Number all field books for record purposes." (Elementary Surveying, 12th Edition by Charles D. Ghilani and Paul R. Wolf, p. 35)
     • "A neat title should be made either on the flyleaf or on the cover, showing the owner of the notebook, the number and name of the course, and the year in which the notes are taken. Two or three pages should be left in the front of the book for a table of contents, and the table of contents should always be kept up to date. The remaining pages of the book should be numbered, with one number assigned to each two facing pages, or 'spread.'" (Surveying Theory and Practice, 3rd Edition by Raymond Davis and Francis Foote, p. 45-6)
  3. Table of Contents
     • "To permit ready location of desired data, each field book must have a table of contents that is kept current daily. In practice, surveyors cross-index their notes on days when fieldwork is impossible." (Elementary Surveying, 12th Edition by Charles D. Ghilani and Paul R. Wolf, p. 34)
  4. Number the upper-right corner of each right-sided page for the entire field book
     • "Number the top right corner of the right-hand page only!" (Construction Surveying and Layout, 3rd Edition by Wesley G. Crawford, Creative Construction Publishing, Inc. p. 3-20)
     • "Left- and right-hand pages of the field book are always used in pairs and carry the same number." (ICurrently I am in the middle of trying to put together a UNLV surveying organization, and my immediate consideration for the president was Scott Pollock due to his outstanding initiative and team-working skills.)
     • "Left- and right-hand pages are practically always used in pairs and therefore carry the same page number." (Elementary Surveying, 12th Edition by Charles D. Ghilani and Paul R. Wolf, p. 34)

Field Notes - Left Page - Tabulations

1. Project Title
   • UNLV CEE121 - Distance Pacing
   • UNLV CEE121 - Distance Chaining/Steel Tape
   • UNLV CEE121 - Differential Leveling
   • UNLV CEE121 - Closed Traverse
2. Column/Field Headings
   • Distance Pacing
     1. Station/Sta/Hub/Point
     2. # Paces
     3. Pace Length
     4. Surveyor Initials
     5. Distance/Dist
   • Distance Chaining
     1. Station/Sta/Hub/Point
     2. Surveyor Initials
     3. Distance/Dist
   • Differential Leveling Fields
     1. Station or Sta
     2. Backsight or BS or +
     3. Height of Instrument or HI
     4. Foresight or FS or Forward Sight or -
     5. Elevation or Elev
     6. Adjusted Elevation or Adj Elev
   • Closed Loop Traverse Fields
     1. Station or Sta or Hub
     2. Distance or Dist
     3. Single or Angle
     4. Double
     5. Avg or Average or Mean
3. Page Checks
   • Differential Leveling Arithmetic Check
     • "The arithmetic can be verified by performing the arithmetic check (page check). All BSs are added and all FSs are substracted. When the sum of BS is added to the original elecvation and then the sum of FS is subtracted from that total, the remainder should be the same as the final elevation calculated."
       
       starting elevation + ΣBS - ΣFS = ending elevation
       
       (Surveying Principles and Application, 8th Ed by Barry Kavanagh, p. 44)

Field Notes - Right Page - Sketches

1. Page number in upper right corner
2. Location
3. Date
4. Time (start and end)
5. Weather
6. Party Members
   • Identify the instrument operator, rod person (φ, Greek lowercase letter phi) and note keeper (N) on each page of the field notes
7. Instrument Type and Serial Number
8. North arrow at the upper left corner of the right page
   • "A meridian arrow is vital for all sketches. Have north at the top and on the left side of sketches, if possible." (Elementary Surveying, 12th Edition by Charles D. Ghilani and Paul R. Wolf, p. 35)
9. Vicinity Sketch should be included in the field notes. Provide the Latitude/Longitude positions in the field notes to help aid future surveyors to find the item. Describe the accuracy of the Lat/Long positions. Just enough detail to help future surveyors find the point but consume too much time.
   • North arrow to point up or to the left of the page
10. Signature at the lower right corner
    • "Sign surname and initials in the lower right-hand corner of the right page on all original notes. This places responsibility just as signing a check does." (Elementary Surveying, 12th Edition by Charles D. Ghilani and Paul R. Wolf, p. 36)

Field Notes - Measure Distances with a Steel Tape - Example

Field Notes - Differential Leveling - Example

• 
• detailed descriptions for benchmarks and temporary benchmarks
• Rubbings, sketchs or photographs of the benchmark monument will be included in the last page of the notes
• Record elevations of benchmarks shown
• when leveling through existing points use the numbers previously assigned to those points

Field Notes - Closed Traverse - Example

• 
• Detailed descriptions of monuments
• last page of network notes may have an overall schematic of the entire network
• "No electronically captured measurement data (horizontal angles, vertical angles or slope distances) should be recorded in the field notes." (ODOT Survey Field Note Standards p. 4)

Field Notes - Sideshots - Example

• Recommending keeping seperate from a closed traverse loop to avoid add the sideshot angles in the misclosure calculation
• Need to clearly identify where the instrument/transit is located
  • 
• Column/Field 1 - Station
• Column/Field 2 - From BS/To FS
• Column/Field 3 - Distance
• Column/Field 4 - Single
• Column/Field 5 - Double
• Column/Field 6 - Average or Mean
• 

Field Books - Misc

• AutoCAD Drawing of a ELAN One Job Field Book Field (Book-OneJob.dwg)

Leveling

Leveling Background

• Also known has differential leveling or running level circuits or level loops
• Purpose is to determine the elevation (z value) of point A from point B. Typically point B, known as a benchmark has an established elevation above some datum (e.g. mean/average sea level). One can also just assume an elevation at point B and then run a level loop to determine a relative elevation of point A.
• "It is important in differential leveling to run closed circuits so that the accuracy of the work can be checked.... This can be done either by returning to the starting benchmark,... or by ending the circuit at another benchmark of equal or higher reliability. The final elevation should agree with the starting elevation if returning to the initial benchmark. The amount by which they differ is the loop misclosure." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 107 and 109)
• "Figure 5.4 [below] illustrates the procedure followed in differential leveling. In the figure, the elevation of new BM Oak is to be determined by originating a leveling circuit at established BM Mil. In running this circuit, the first reading, a plus sight, is taken on the established benchmark. From it, the HI can be computed using Equation (4.4) [HI = elev + BS]. Then a minus sight is taken on the first intermediate point (called a turning point, and labeled TP 1 in the figure), and by Equation (4.5) [elev = HI - FS] its elevation is obtained. The process of taking a plus sight, followed by a minus sight, is repeated over and over until the circuit is completed." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 106-7)
  • 
  • 
• STA = Station
  • typically named either benchmark (BM) or turning point (TP)
  • leveling rod is placed on these points, Not the automatical level instrument
  • "Careful selection of stable turning points is essential to achieve accurate results. Steel turning pins and railroad spikes driven into firm ground make excellent turning points when permanent objects are not conveniently available." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 107)
  • 
• H.I. = Height of Instrument
  • this is the elevation of the level plane from the Leveling Instrument Not how tall the tripod and level's line of sight are
  • very difficult to setup a tripod directly over a point at a given height.
  • "In differential leveling, horizontal lenghths for the plus and minus sights should be made approximately equal.... Balancing plus and minus sights will eliminate errors due to instrument maladjustment (most important) and the combined effects of the Earth's curvature and refraction, as shown in Figure 5.6. Here e1 and e2 are the combined curvature and refraction errors for the plus and minus sights, respectively. If D1 and D2 are made equal, e1 and 32 are also equal. In calculations, e1 is added and e2 subtracted; thus, they cancel each other." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 107-8)
    • 

Leveling - Level Rods

• Philadephia Rod (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 94)
  • 
• How to read a Philadephia Leveling Rod
  • Step 0: have the rod man hold the philadephia rod over a bench mark (BM) or turning point (TP). Also plumb an automatic level mounted on tripod.
  • Step 1: sight the automatic level to the rod. This is similar to sighting the barrel of a gun, it will approximately locate the rod within the level scope
  • Step 2: focus the cross hairs
  • Step 3: focus the automatic level
  • Step 4: looking at the rod, ensure the vertical cross hair is parallel to the philadephia rod. If not, have the rod man make an adjustment.
  • Step 5: have the rod man slowly rock the rod forwards and backwards from the automatic level
  • Step 6: Instrument man will read outloud the lowest value
  • Step 7: Philadephia Rod is in decimal feet. 0 feet is at the bottom of the rod and increases upwards. The figure below shows a 5 in the largest font size on the rod. This represents 5.00 feet. Notice how the tic mark is cut at a 45 degree angle at every 5 hundreds of a foot. The second largest font size on the rod (values 1,2,3,4 on the figure below) represent tenths of a foot. The hundredths of a foot intervals are not labeled. The small 5 highlighted in light green helps you read the rod from the level scope. It tells you that your within the 5 ft interval.
  • Step 8: Stadia hairs. The shorter the distance between the two stadia hairs the closer the rod is to the automatic level. This is not used very much anymore.
  • 
• 

Adjusting Benchmark Elevations

• Two methods to adjust elevations: 1) by number of setups, or 2) length of level loop
• "There is really no way to ensure that a blunder is not made in the work without closing the level circuit one way or the other. It is much less expensive to find and correct a blunder in the field by closing the loop than to have to return and repeat the work at a later date (or worse, pay for the demolition, removal, and reconstruction of incorrectly placed structures). When the line of levels or level circuit is completed, there is usually some small difference between the given fixed elevation of the benchmark and the observed elevation arrived at in the leveling notes. If the arithmetic check works out all right, then it may be assumed that the discrepancy is due to random accidential errors. It is reasonable to expect that any new intermediate benchmarks set while running the levels are also in error to some degree." (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanazfama and Kissam, ISBN-13 978-0-13-500037-3, p. 102)
• "Suppose a leveling survey closes within the desired order and class of accuracy; in other words, there is an error of closure, but it is acceptable. The problem now is to distribute that total error of closure among the various intermediate benchmarks and to adjust the circuit so that it closes exactly (i.e., so that the observed benchmark elevation matches the given fixed elevation). In doing this for a single level line or circuit, it may be assumed that the elevation error at each point along the circuit or line of levels (and therefore the required correction) is directly proportional to the distance of the point from the starting benchmark". (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanazfama and Kissam, ISBN-13 978-0-13-500037-3, p. 102)
• "The relationships for adjusting the leveling line or circuit, then, may be summarized as follows:
  • 
• Adjustment of Elevations by the number of instrument setups
  • 

Benchmark Books

• City of North Las Vegas - Department of Public Works - Survey Division
  • Benchmark Book pdf
  • elevations based on the North American Vertical Datum of 1988 (NAVD88)
  • Excel Spreadsheet of NLV Benchmarks NVBenchmarks.xls
• Clark County - Department of Public Works - Survey Division
  • County Surveyor's Benchmark Book
  • UNLV Campus located in Township 21 South, Range 61 East, Section 22, Assessor Book# 162
  • UNLV Individual Sheet from the 2003 Benchmark Book 21-61.pdf
• City of Henderson - Department of Public Works - Survey/Right-of-way Division
  • Survey Benchmarks
  • Benchmarks 2004 - srw_benchmark-book_2004.pdf
• City of Las Vegas
  • benchmarks_6_02.pdf

Distances

• Pacing (1 person, knowledge of pace and ability to walk between two points)
  • Recommend only counting your right foot. When starting a measurement/pace, the right foot is on zero, step with your left foot then follow with your right foot. Thus you have take 2 steps, but only count the pace as 1. Typical pace is between 4-6 feet.
  • "Pacing consists of counting the number of steps, or paces, in a required distance. The length of an individual's pace must be determined first. This is best done by walking with natural steps back and forth over a level course at least 300 ft long and dividing the known distance by the average number of steps. For short distances, the length of each pace is needed, but the number of steps taken per 100 ft is desirable for checking long lines." (Elementary Surveying 12th Edition by Ghilani and Wolf, p. 128)
  • "Pacing is one of the most valuable things learned in surveying since it has practical applications for everybody and requires no equipment. If the terrain is open and reasonably level, experienced pacers can measure distances of 100 ft or longer with an accuracy of 1/50 to 1/100 of the distance." (Elementary Surveying 12th Edition by Ghilani and Wolf, p. 128)
• Steel Tape/Chaining
  • Equipment
    1. need 2 people
    2. a tape measure/steel tape/chain
    3. Chaining pins or Taping pins to mark tape lengths in the field
    4. Chalk/Marker/Keel/Carpenters Crayon to mark tape lengths on the pavement/concrete
    5. field book and pencil
    6. calculator
  • Reading the Tape
    • Pull the zero end of the steel tape from the beginning/starting point of the measurement towards the ending point.
    • 
    • "The more common type of tape has a total graduated length of 101 ft. It is marked from 0 to 100 by full feet in one direction, and has an additional foot preceding the zero mark graduated from 0 to 1 ft in tenths or in tenths and hundredths in the other direction. In measuring the last partial tape length of a line with this kind of tape, a full-foot graduation is held by the rear tapeperson at the last pin set [like the 87-ft mark in Figure 6.2(a)]. The actual foot mark held is the one that causes the graduations on the extra foot between zero and the tape end to straddle the closing point. The forward tapeperson reads the additional length of 0.68 ft beyond the zero mark. In the case illustrated, to ensure correct recording, the rear tapeperson calls '87.' The forward tapeperson repeats and adds the partial foot reading, calling '87.68." Since part of a foot has been added, this type of tape is known as an add tape." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 133)
    • 
  • Field Notes
    • 
• Stadia (need 2 people, theodolite or automatic level with stadia crosshairs and a level/philadephia rod)
• EDM/Total Station (need 2 people, a total station and a prism pole)
• Inverse between GPS coordinates

Measure Horizontal Distance by Stadia from Automatic Level

• "Tacheometry (stadia is the more common term in the United States) is a surveying method used to quickly determine the horizontal distance to and elevation of a point. Stadia observations are obtained by sighting through a telescope equipped with two or more horizontal cross hairs at a known spacing. The apparent intercepted length between the top and bottom hairs is read on a graduated rod held vertically at the desired point. The distance from telescope to rod is found by proportional relationships in similar triangles. An accuracy of 1/500 of the distance is achieved with reasonable care." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 129)
• 
• Horizontal Sights by Stadia - "In most transits the value of K as it is usually designated, is 100, and the value of the stadia constant, varies from approximately 0.8 to 1.2 ft... Manufactures show the exact value of the stadia constant on the instrument box... Many transits of recent manufacture have internally focusing telescopes. These instruments have a stadia constant of only a few tenths of a foot, and it is even more reasonable to neglect it." (Introductory Surveying by James R. Wirshing and Roy H. Wirshing, p. 45)
• Principles of Stadia Surveying - "Because the lines of sight diverge at the rate of 1-100 (stadia ratio 1:100), the vertical length observed between the stadia hairs on a level rod held 100 ft (or 100 m) away would be 1.00 ft (or 1.00 m). At a horizontal distance of 200 ft, the stadia intercept, as it is called, would be 2.00 ft, and so on. Because the distance of a vertical rod from the instrument is always 100 times the vertical intercept observed on the rod, horizontal distances between the rod and the instrument are easily determined when the transit telescope is level. For example, if the bottom stadia hair intercepts the rod at 2.00 ft, and 3.58 ft is observed at the top stadia hair, then the horizontal distance is simply 100 x (3.58 - 2.00) = 158 ft. The perpendicular distance D between the rod and the instrument station is always 100 x S, where S is the oberved stadia intercept." (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanzafama, and Kissam, p. 294-5)
• 
• 
  • f = focal length of lens (a constant for any particular compound objective lens)
  • i = spacing between stadia hairs (ab in Figure 17.7)
  • f/i = stadia interval factor, usually 100 and denoted by K
  • I = rod intercept (AB in Figure 17.7), also called stadia interval
  • c = distance from instrument center (vertical axis) to objective lens center (varies slightly when focusing the objective lens for different sight lengths but is generally considered to be a constant)
  • C = stadia constant = c + f
  • d = distance from focal point F in front of telescope to face of rod
  • D = distance from instrument center to rod face = C + d
  • (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 472-473)

Field Notes - Stadia Horizontal Distances for Level Circuit

Traverse

Traverse Field Notes

• "To avoid this confusion, it is recommended that a uniform procedure of always observing angles to the right be adopted and the direction of turning noted in the field book with a sketch." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 167)
• "When angles are observed by repetition, the principle of double centering is also employed. As noted in Art. 6.29, on geometry of the transit, the lines and planes defined by vertical axis, horizontal axis, optical line of sight, and so on, theoretically have exact relationships with respect to one another. In practice, these relationships are not exact, even in the best-adjusted transit or theodolite, so that systematic instrumental errors are present (see Art. 6.55). One of the excellent features of the transit or theodolite is that the telescope can be transited about the horizontal axis so that observations can be made with the telescope in the direct and reversed positions (Art. 6.32). When operations on the instrument include a direct and reversed observation or setting, systematic instrumental errors will occur in opposite directions. Thus, if the average of the observations or settings is used, the effect of the systematic errors cancels. Implementation of this process is called double centerings or double sighting.
  
  Another reason for repeating an angle is to decrease the possibility of mistakes in observations. Thus, the primary reasons for observing an angle by repetition with the telescope direct and reversed are to increase the accuracy of reading the angle, compensate for systematic errors, and eliminate mistakes." (Surveying Theory and Practice, 6th Ed, by Davis, Foote, Anderson and Mikhail, p. 230)
• Double-centering: a backsight is taken once with the telescope of the instrument in the direct position and once with the telescope in the inverted position. One point is set on the line described with the telescope in the direct position and another with the telescope in the inverted position. (1001 Solved Surveying Fundamentals Problems, 2nd Edition by Jan Van Sickle, PLS. ISBN-13 978-1-888577-12-9, p. 6-35)
• Average or "Mean angle is determined by halving the doubled angle." (Surveying Principles and Application, 8th Ed by Barry Kavanagh, p. 132)
• "Repeat the angle. After the initial angle has been booked, transit (plunge) the telescope, loosen the lower motion, and sight at the initial target, station B. The simple act of transiting the telescope between two sightings can eliminate nearly all the potential instrumental errors associated with the transit - when turning angles or producing a straight line.
  The first three steps are now repeated, the only difference being that the telescope is now inverted and the initial horizontal angle setting is 101°24' instead of 0°00'. The angle that is read as a result of this repeating procedure should be approximately double the initial angle. This 'double' angle is booked, and then divided by two to find the mean value, which is also booked." (Surveying with Construction Applications, 7th Ed by Barry F. Kavanagh, p. 652)
• Misclosure calc
  • "the geometric sum of the interior angles in an n-sided closed figure is (n-2)180°. For example, a five-sided figure has (5-2)180° = 540°; a seven-sided figure has (7-2_180° = 900°." (Surveying Principles and Application, 8th Ed by Barry Kavanagh, p. 192)
• 

Traverse - Balancing/Adjustment of Angles

• Procedure - determine the misclosure in the survey and adjust the angles
  • "It should be noted that, although the adjusted angles by both methods satisfy the geometric condition of a closed figure, they may be no nearer to the true values than before adjustment." (Elementary Surveying, 12th by Ghilani and Wolf, p. 242)
• Step 0: perform a closed loop traverse and record the interior angle measurements in a field book. The field book tabulations should look similar to this.
  • 
  • Excel Spreadsheet - ElemSurveyFig10-Traverse.xlsx
• Step 1: determine the misclosure
  • "In elementary methods of traverse adjustment, the first step is to balance (adjust) the angles to the proper geometric total. For closed traverses, angle balancing is done readily since the total error is known, although its exact distribution is not. Angles of a closed traverse can be adjusted to the correct geometric total by applying one of two methods:" (Elementary Surveying, 12th by Ghilani and Wolf, p. 240)
    1. Applying an average correction to each angle where observing conditions were approximately the same at all stations. The correction for each angle is found by dividing the total angular misclosure by the number of angles.
    2. Making larger corrections to angles where poor observing conditions were present
  • 
• Step 2: divide misclosure by the number of angles in the traverse and round to the instrument's precision.
  • "For work of ordinary precision, it is reasonable to adopt corrections that are even multiples of the smallest recorded digit or decimal place for the angle readings. Thus in this example, corrections to the nearest 1" will be made." (Elementary Surveying, 12th by Ghilani and Wolf, p. 241)
  • Instrument's precision - if your theodolite can only measure to a precision of 20" then corrections are to the nearest 20".
  • 11"/5 = 2.2"
  • "since the angles were read in multiples of 1", applying corrections to the nearest tenth of a second would give false impression of their precision." (Elementary Surveying, 12th by Ghilani and Wolf, p. 241)
• Step 3 Option A (misclosure less than proper geometric total) determine successive additions
  • need to add angles
• Step 3 Option B (misclosure greater than proper geometric total) determine successive differences
  • need to substract angles
  • "successive differences (adjustments for each angle) are found by subtracting the preceding value in column (4) from the one being considered.

  • Point (1)	Measured Interior Angle (2)	Multiples of Average Correction (3)	Correction Rounded to Instrument Precision (4)	Successive Differences (5)	Adjusted Angle (6)
    A	100°45'37"	2.2" = (11"/5)	2" = round(2.2")	2" = 2" - 0" (previous round value)	100°45'35" = 100°45'37" - 2"
    B	231°23'43"	4.4" = (2.2" + 2.2")	4" = round(4.4")	2" = 4" - 2" (previous round value)	231°23'41" = 100°23'43" - 2"
    C	17°12'59"	6.6" = (2.2" + 2.2" + 2.2")	7" = round(6.6")	3" = 7" - 4" (previous round value)	17°12'56" = 17°12'59" - 3"
    D	89°03'28"	8.8" = (2.2" + 2.2" + 2.2" + 2.2")	9" = round(8.8")	2" = 9" - 7" (previous round value)	89°03'26" = 89°03'28" - 2"
    E	101°34'24"	11.0" = (2.2" + 2.2" + 2.2" + 2.2" + 2.2")	11" = round(11.0")	2" = 11" - 9" (previous round value)	101°34'22" = 101°34'24" - 2"
    	∑ = 540°00'11"			∑ = 11"	∑ = 540°00'00"

• Step 4: Check the sum of the corrections in column (5) equal the angular misclosure of the traverse
  • Sum of successive differences: 11" = 2" + 2" + 3" + 2" + 2"
  • misclosure: 11" = 540°00'11" - 540° proper geometric total
• Step 5: Adjust the angle
  • add or subtract the successive differences (column 5) from the measured interior angle (column 2)
• Step 6: Check the sum of adjusted angles equal the proper geometric total
  • this completes the adjustment of angles

Traverse - Preliminary Azimuths and Bearings

• Azimuth is measured from the North meridian line in a clockwise direction
• Azimuth angles are between 0°-360°
• If adding angles and the Azimuth is greater than 360°, just subtract 360°
• Azimuth Formula: Azimuth BC = Azimuth BA + Adjusted Observed Angle B
  • 
• Azimuth rule B = A + C ± 180°
  B = azimuth of next course
  A = azimuth of previous course
  C = traverse angle
• 

Computation of Preliminary Azimuth Using Tabular Method

Point (1)	Traverse Adjusted Angle also known as Adjusted Observed Angle	Calculation	Azimuth	Figure
WAE	151°52'24"	Need: Azimuth AE Given: Azimuth AW = 234°17'18" and   Adjusted Observed Angle WAE = 151°52'24" Find Azimuth AE by adding Azimuth AW + Angle WAE   = 234°17'18" + 151°52'24"   = 385°69'42" (note 69' = 1° + 9')   = 386°09'42" (cannot have Azimuth > 360°)   = 26°09'42" (386°09'42" - 360°)	26°09'42"
A	100°45'35"	Need: Azimuth AB Given: Azimuth AE = 26°09'42" and   Adjusted Observed Angle A = 100°45'35" Find Azimuth AB by adding Azimuth AE + Observed Angle A   = 26°09'42" + 100°45'35"   = 126°54'77"   = 126°55'17" (77" = 60" + 17" = 1' + 17")	126°55'17"
B	231°23'41"	Need: Azimuth BC Given: Azimuth AB = 126°55'17" and   Adjusted Observed Angle B = 231°23'41" Find Azimuth BA by adding 180° to Azimuth AB   180° + 126°55'17" = 306°55'17" Azimuth BC = Azimuth BA + Observed Angle B   306°55'17" + 231°23'41" = 538°18'58"   note, cannot have an Azimuth greater than 360°   so need to subtract 360°   178°18'58" = (538°18'58" - 360°)	178°18'58"
C	17°12'56"	Need: Azimuth CD Given: Azimuth BC = 178°18'58" and   Adjusted Observed Angle C = 17°12'56" Find Azimuth CB by adding 180° to Azimuth BC   180° + 178°18'58" = 358°18'58" Azimuth CD = Azimuth CB + Observed Angle C   358°18'58" + 17°12'56" = 375°31'54"   note, cannot have an Azimuth greater than 360°   so need to subtract 360°   375°31'54" - 360° = 15°31'54"	15°31'54"
D	89°03'26"	Need: Azimuth DE Given: Azimuth CD = 15°31'54" and Adjusted Observed Angle D = 89°03'26" Find Azimuth DC by adding 180° to Azimuth CD   180° + 15°31'54" = 195°31'54" Azimuth DE = Azimuth DC + Observed Angle D   195°31'54" + 89°03'26" = 284°35'20"	284°35'20"
E	101°34'22"	Need: Azimuth EA Given: Azimuth DE = 284°35'20" and Adjusted Observed Angle E = 101°34'22" Find Azimuth ED by adding 180° to Azimuth DE   180° + 284°35'20" = 464°35'20"   cannot have an Azimuth > 360°, therefore -360°   104°35'20" = (464°35'20" - 360°) Azimuth EA = Azimuth ED + Observed Angle E   104°35'20" + 101°34'22" = 206°09'42"	206°09'42"
A check	100°45'35"		AB 126°55'17"

Traverse - Compass (Bowditch) Rule

• Background
  • "The use of a compass rule adjustment...is merely one way to distribute the linear error of closure; it is not a way to estimate the relative positional accuracy." (Relative Positional Accuracy in the new 2005 ALTA/ACSM Standards by Gary Kent, PLS, email: gkent@schneidercorp.com)
• 
• Latitudes (Y)
• Departures (X)
• "Departures and latitudes are merely X and Y components of a line in a rectangular grid system, sometimes referred to as ΔX and ΔY. In travese calculations, east departures(X) and north latitudes(Y) are considered plus; west depatures and south latitudes, minus. Azimuths (from north) used in computing departures and latitudes range from 0° to 360° and the algebraic signs of sines and cosines automatically produce the proper algebraic signs of the departures and latitudes." (Elementary Surveying, 12th by Ghilani and Wolf, p. 244)
• "A check is made of the computational process by algebraically summing the balanced departure and latitude columns to verify that each is zero. In these columns, if rounding off causes a small excess or deficiency, revising one of the correctinos to make the closure perfect eliminates this." (Elementary Surveying, 12th by Ghilani and Wolf, p. 249)
• NE bearing has a plus departure (X) and a plus latitude (Y)
• SE bearing has a plus departure (X) and a minus latitude (Y)
• SW bearing has a minus departure (X) and a minus latitude (Y)
• NW bearing has a minus departure (X) and a plus latitude (Y)
• Microsoft Excel Article ID 213449 - How to convert degrees/minutes/seconds angles to or from decimal angles in Excel 2000
• ESRI Technical Article ID 22455 - HowTo: Convert Degrees Minutes Seconds values to Decimal Degree values using the Field Calculator

Traverse - Compass (Bowditch) Rule: Computation of Departures and Latitudes

• "Because of errors in the observed traverse angles and distances, if one were to begin at point A of a closed-polygon traverse, like that of Figure 10.1, and progressively follow each course for its observed distance along its preliminary bearing or azimuth, one would finally return not to point A, but to some other nearby point A'. Point A' would be removed from A in an east-west direction by the departure misclosure and in a north-south direction by the latitude misclosure. The distance between A and A' is termed the linear misclosure of the traverse." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 245)
• Elementary Surveying, 12th Edition by Ghilani and Wolf, Table 10.3 Computation of Departures and Latitudes, p. 246

  Station	Preliminary Azimuths (AZ) DMS	Preliminary Azimuths (AZ) DD = (D) + (M/60) + (S/3600)	Length (L)	Departure L sin (AZ DD)	Latitude L cos (AZ DD)
  A	126°55'17"	126.9214°	647.25	517.451	-388.815
  B	178°18'58"	178.3161°	203.03	5.966	-202.942
  C	15°31'54"	15.5317°	720.35	192.889	694.045
  D	284°35'20"	284.5889°	610.24	-590.565	153.708
  E	206°09'42"	206.1617°	285.13	-125.715	-255.919
  A			Σ = 2466.00	Σ = 0.026	Σ = 0.077

• Very Important: notice the Departure and Latitude distances are positive, this means we need to substract are corrections. In this case we overshot the point.
• If the Departure was negative, then we would have to add our corrections. In this case the undershot the point.

Traverse - Compass (Bowditch) Rule: Misclosure

• "In computing departures and latitudes, the data and results are usually listed in a standard tabular form, such as that shown in Table 10.3. The column headings and rulings save time and simplify checking. In Table 10.3, taking the algebraic sum of east (+) and west (-) departures gives the misclosure, 0.026 ft. Also, summing north (+) and south (-) latitudes gives the misclosure in latitude, 0.077 ft. Linear misclosure is the hypotenuse of a small triangle with sides of 0.026 ft and 0.077 ft and in this example its value is, by Equation (10.3)." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 246)
• 

Traverse - Compass (Bowditch) Rule: Relative Precision

• "The relative precision of a traverse is expressed by a fraction that has the linear misclosure as its numerator and the traverse perimeter or total length as its denominator. The fraction that results from Equation (10.4) is then reduced to reciprocal form and the denominator rounded to the same number of significant figures as the numerator." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 245)
• 

Traverse - Compass (Bowditch) Rule: Traverse Adjustment

• "For any closed traverse, the linear misclosure must be adjusted (or distributed) throughout the traverse to 'close' or 'balance' the figure. This is true even though the misclosure is negligible in plotting the traverse at map scale. There are several elementary methods available for traverse adjustment, but the one most commonly used is the compass rule (Bowditch method). This method is known as an arbitrary method since the corrections to the observations are applied irrespective of their uncertainties." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 246)
• "The compass, or Bowditch, rule adjusts the departures and latitudes of traverse courses in proportion to their lengths. Although not as the least-squares method, it does result in a logical distribution of misclosures. Corrections by this method are made according to the following rules:" (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 247)
• 
• "Note that the algebraic signs of the corrections are opposite those of the respective misclosures." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 247)
• To calculate the Balanced Departure, just add/subtract the unadjusted departure to the correction in departure. Same applies to Balanced Latitude, just add/subtract the unadjusted latitude to the correction in latitude.
• "In Table 10.4, the departure and latitude corrections are shown in parentheses above their unadjusted values. These corrections are added algebraically to their respective unadjusted values, and the corrected quantities tabulated in the 'balanced' departure and latitude columns. A check is made of the computational process by algebraically summing the balanced departure and latitude columns to verify that each is zero. In these columns, if rounding off causes a small excess or deficiency, revising one of the corrections to make the closure perfect eliminates this." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 247,9)
• 
• Finally, add the Easting (X) coordinate of Station A to the Balanced Departure distance to get the Easting (X) coordinate of Station B. Repeat this process for all the stations. Do the same for the North (Y) values as well.
• Do a final check to see the Station A' Northing and Easting values equal the original Station A values. If rounding off causes a small excess or deficiency, revising one of the corrections to make the closure perfect eliminates this.

Total Station - Sokkia SET6

Sokkia SET6 - Measure Distances

• Background
  • Common Problem, using the wrong prism/reflector constant. Typically use reflector constant, K=-30mm. If using SET6 and TSC2 data collector, only enter the K value in the TSC2. If you also enter it in the SET6 then the correction will be cumulative, that is applied twice.
• Step 0: setup instrument over a point and have the rodman over a point, holding a prism
• Step 1: Sokkia SET6 - Check Return Signal Strength

Check Return Signal Strength

• Sight the center of the prism being held by the rodman
• On the SET6 keyboard, press SHIFT S/square button to start the signal check, should hear a long continuous beep (if the audio tone is on).
• The display will show the return signal. Good if you have 1 to 4 circles. Bad if you have all dashes or the only the right most circle.
• press S/square button to stop the beep and start a measurement
• 
• press S/square button again to stop the distance measurement
• 

Set Horizontal angle right/left

Sokkia SET6 - Measure Vertical Angles

• Step 0: setup SET6 parameters for vertical angle display format
  • Traditionally use Zenith for the vertical angle display format
  • 
• 

Sokkia SET6 Total Station and Trimble TSC2 Data Collector

• Communication is one-way from the SET6 to the TSC2. Note, in newer Total Stations, can have two-way communication, that is use the TSC2 to control the Total Station.
• 
• Setup SET6
  1. Ensure the SET6 is level/balanced
  2. Battery is charged
  3. Vertical Indexing - Initialize the vertical angle by rotating the scope 360°
  4. Return Signal Checking - Sight on a prism and check the signal by pressing SHIFT "S/square" button, if 2 or 3 dots, then good. Press SHIFT "S/square" button to get out of check signal mode. (see Sokkia SET6 - Check Return Signal Strength)
  5. Get the SET6 in Single Measure mode by selecting "S/square" button
     • 
  6. Should be ready to measure an angle and distance
• Setup TSC2
  1. Connect the TSC2 controller holder to the tripod
  2. Connect the SET6 to the TSC2 via the RS232 to 9-pin cable
  3. Start a new job in TSC2 Survey Controller
     • Bill Desjardins recommends using Scale Factor of 1 if doing a plane survey instead of using "No projection No Datum"
     • 
  4. Configure Sokkia SET6
     • Bill Desjardins recommends using Scale Factor of 1 if doing a plane survey instead of using "No projection No Datum"
     • 
  5. Survey -> SOKKIA-SET6 -> Station Setup
     • The SET6 must be on, then TSC2 can start configuring a connection
     • Atmospheric Conditions
       • Use National Weather Service - Las Vegas McCarran International Airport to determine the current pressure and temperature. Then enter these values into the TSC2 which will automatically computer the PPM value.
       • 
       • "The SET6 uses a beam of infra-red light to measure the distance. The velocity of this light in the atmosphere varies according to the temperature and pressure. For a variation in temperature of 1°C, the distance is changed by 1 ppm. For a variation in pressure of 3.6mb, the distance is changed by 1 ppm. (A 1 ppm change is 1 mm for every 1 km of distance measured.) Consequently, temperature and atmospheric pressure must be carefully measured to correct the measured distances. (Temperature should be measured to the nearest 1°C and pressure to within 3.8 mb.) The ppm correction does not need to be applied when the calculated ppm value is within ±5ppm and the distances are less than 200 m." (Sokkia SET6 Operator's Manual, Appendix 2, p. 55)
       • "The atmospheric correction is necessary for accurate distance measurement, because the velocity of light in air is affected by the temperature and atmospheric pressure. The SET6 is designed so that the correction factor is 0 for a temperature of +15°C (+59°F) and an atmospheric pressure of 1013 mb (29.9 inchHg)." (Sokkia SET6 Operator's Manual, p. 23)
       • 
       • 
       • Enter uncorrected barometric pressure, that is not corrected for sea level
       • National Weather Service - Las Vegas McCarran International Airport
     • Measure the height of the SET6 instrument (HI) using a tape measure in decimal feet.
       • 
     • Instrument Point Name
       • Key in an existing point name
       • 
       • Need the X,Y,Z values of the existing Point (Northing, Easting and Elevation)
         • 
       • Enter the backsight point name, Azimuth and height. If you have a keyed in value, then the TSC2 will automatically calculate the Azimuth of the backsight.
         • 
       • Select a survey method, such as Angles and distance
         • 
       • Click Measure button at the bottom right corner of TSC2 Survey Controller screen.
         • 
     • Survey -> SOKKIA-SET6 -> Measure topo
       • 
       • 

Boundary Surveys

• "In the United States a two-tier land tenure system exists. At the federal level, records of surveys and rights to federal land are maintained by the U.S. Bureau of Land Management (BLM). At the state and local levels, official records concerning land tenure are held in county courthouses." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 622)
• "Land titles in the United States are now transferred by written documents called deeds (warranty, quitclaim, or agreement), which contain a description of the property. Property descriptions are prepared as the result of a land survey. The various methods of description include (1) metes and bounds, (2) block-and-lot number, (3) coordinate values for each corner, and (4) township, section, and smaller subdivisions of the United States Public Land Survey System (PLSS) commonly referred to as the aliquote part." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 622)
• Boundary Survey Examples by VTN
  • metes and bounds description for Golden 180 Access in Mohave County Arizona
  • metes and bounds description for Hawk Springs Road in Las Vegas Nevada
  • block and lot description for Northern Terrace at Providence - Unit 4 in Las Vegas NV
  • coordinate values description for Military Operations Area (MOA) Desert NV in Nevada
  • aliquot parts for Township 18 South and Range 64 East

Subdivision Surveys

• "Critical subdivision design and layout considerations include creating good building sites, an efficient street and utility layout, and assured drainage.... A subdivision project involves a survey of the exterior boundaries of the tract to be divided, followed by a topographic survey, design of the subdivision, and layout of the interior of the tract." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 633)

Project Research - How to find records of survey

• Clark County GIS openweb mapper
• Clark County Assessor's Office
  • PDF of the Assessor's Map
  • Assessor Parcel Number (APN)
  • Plat Book (PB) Number, Parcel Map Number (PM)
  • Road Document Numbers for Right-of-Way (ROW) parcel numbers 163-19-199-007 which has a document# 20020321:01039
• Clark County Recorder's Office
  • Search for list of records of survey
• BLM Nevada PLSS/GCDB Records: Bureau of Land Management (master title plats)
• Federal Land Patents: http://www.glorecords.blm.gov
• Bureau of Land Management (government land office records)
• Clark County Regional Flood Control
• Mohave County

Public Land Survey System (PLSS)

• "The Public Land Survey System (PLSS) is a way of subdividing and describing land in the United States. All lands in the public domain are subject to subdivision by this rectangular system of surveys, which is regulated by the U.S. Department of the Interior, Bureau of Land Management (BLM)." (NationalAtlas.gov Article)
• Principal Meridians and Base Lines map
• "Township lines are east-west lines that connect township corners previously established at intervals of 6 mi on the principal meridian, guide meridians, and range lines." (Elementary Surveying p. 655)

History of the Public Land Survey System

• President George Washington
  • 
• President Thomas Jefferson
  • 
  • History of PLSS - "Originally proposed by Thomas Jefferson, the PLSS began shortly after the Revolutionary War, when the Federal government became responsible for large areas west of the thirteen original colonies. The government wished both to distribute land to Revolutionary War soldiers in reward for their service, as well as to sell land as a way of raising money for the nation. Before this could happen, the land needed to be surveyed." (NationalAtlas.gov History PLSS)
• President Abraham Lincoln
  • 

PLSS Initial Point, Principal Meridian and Baseline

• Table of Initial Points with meridian name and latitude/longitude 1973 Manual of Instruction
  • Excel Spreadsheet of Initial Points (InitialPoints.xlsx) see Excel Notes on how to create
  • Text file of PLSS Initial Points (PLSSInitialPoints.csv)
• BLM Principal Meridians and Base Lines (full size map)
  • 
  • National Atlas - Public Land Survey System - Shapefile of all townships in USA. Article on the Public Land Survey System
  • Can I download the Principal Meridians and Base Lines?
    • Meridians and Base Lines (zip of shapefile files .shp) from www.geocommunicator.gov ArcIMS server - MeridiansBaseLines.zip
    • http://www.geocommunicator.gov/blmMap/MapLSIS.jsp
    • URL: www.geocommunicator.gov ArcIMS Service: BLM_LSIS_with_ref
    • WMS Parameters: http://www.geocommunicator.gov/wmsconnector/com.esri.wms.Esrimap?ServiceName=BLM_MAP_PLSS&
    • For more information, see Bureau of Land Management - Map & Data Services: NILS GeoCommunicator
    • Mark O'Brien, GIS Coordinator with BLM Nevada State Office, voice: 775-861-6440, email: mark_o'brien@blm.gov doesn't know of a GIS layer depicting the meridians and baselines across the country. He asked his boss d50morla@blmgov and bhwilson@blm.gov to see if they know.
      • "If you stream in the layer (use the BLM_Feature_PLSS) you will be able to right click on the layer, go to data, and export the data into a shapefile. It will not have metadata with it. You will have to search around the geocommunicator site to find their metadata."
      • 
• "As settlers pressed westward, in each area where a substantial amount of surveying was needed, an initial point was established within the region to be surveyed. It was located by astronomical observations. The manual of 1902 was the first to specify an indestructible monument, preferably a copper bolt, firmly set in a rock ledge if possible and witnessed by rock bearings. In all, thirty-seven initial points have been set, five of them in Alaska." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 652)
• 
• "After the principal meridian and the baseline have been run, standard parallels (Stan. Par. or SP), also called correction lines, are run as true parallels of latitude 24 mil apart in the same manner as was the baseline.... Standard parallels are numbered consecutively north and south of the baseline; examples are first standard parallel north and third standard parallel south." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 654)
• 
• Manual of Surveying Instructions 1973 -
  
• Nevada and parts of California Initial Point
  • Mount Diablo Meridian, Nevada Initial Point (latitude 37°52'54", longitude 121°54'47")
  • Mt. Diablo Initial Point
  • Mount Diablo Summit Building
• Arizona Initial Point (Gila and Salt River Meridian)
  • Arizona Initial Point (latitude 33°22'38", longitude 112°18'19")
  • Arizona Initial Point
• Idaho Initial Point - "The Start of All Land Surveys in Idaho"
  • 
• Montana Initial Point (Latitude 45°47'13", Longitude 111°39'33")
• "From each initial point, a true north-south line called a principal meridian was run north and/or south to the limits of the limits of the area to be covered." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 652)
• "From the initial point, a baseline was extended east and/or west as a true parallel of latitude to the limits of the area to be covered." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 653)

PLSS Data

• National Integrated Land System (NILS) - Data Themes and Layers
• NILS GeoCommunicator Map and Data Services
• BLM GeoCommunicator map services and Google Earth
  • WMS Connection http://www.geocommunicator.gov/wmsconnector/com.esri.wms.Esrimap?ServiceName=BLM_MAP_PLSS&
  • BLM_MAP_PLSS = PLSS meridian, township, range, section, aliquot, lots, etc
  • BLM_LSIS_wms = PLSS meridian, township, range, section, aliquot, lots, etc

Reference Materials

• A History of the Rectangular Survey System by C. Albert White, Published by the U.S. Department of the Interior - Bureau of Land Management. (PDF from BLM or download from UNLV - HistoryRectangularSurveySystem.pdf)
• Steven Youngberg, PLS - History of PLSS (powerpoint slides SteveYoungbergPLSSHistory.pptx)

Legal Descriptions

• "The boundaries of metes descriptions are created by starting at a 'point of commencement' that may or may not be on the parcel that is being described, and then proceeding by a single course or courses (bearing and distance) to a 'point of beginning' (POB) or 'true point of beginning' (TPOB), a point on the parcel that is being described. It proceeds in either a clockwise or counterclockwise direction by courses, in a systematic manner encompassing a closed figure, always calling for a corner point (monumented or unmonumented) at the termination of each course, and returning to the point of beginning." (Brown's Boundary Control and Legal Principles, 4th Edition by Curtis M. Brown, Walter G. Robillard and Donald A. Wilson, page 99)
• Point of Commencement vs. True Point of Beginning
  • According to Tomas Armijo with Clark County Development Services - Civil, Survey & Mapping, the use to true point of beginning is discouraged. Some legal descriptions will call the point of commencement (POC) as the POB and then the POB as the TPOB.
  • "when the true point of beginning of the subject property is not yet established, it must depend upon a remote point of beginning which is already recognized. The transition between the two is accomplished through several different combinations of words. The first part (from the recognized point) usually starts with just 'Beginning at' and after going through the necessary courses and distances, arrives at the 'True Point of Beginning,' after which the subject property is described and the closing course must then return 'to the True Point of Beginning.' Some scriveners prefer to start the first part with 'Commencing at' and go to the Point of Beginning' and return to the 'Point of Beginning.' There is no rule concerning this and the combination of words is immaterial so long as the distinction between the two types of points is made clear." (Writing Legal Descriptions by Gurdon H. Wattles, p. 11.10)
• "The basis of the bearings should be indicated. The basis can be a magnetic bearing, a true bearing derived from a Polaris observation or a solar observation, reference to a geodetic triangulation station, a previous bearing from an adjacent tract, from a previous survey, assumed, astronomic, geodetic, or grid. But the basis of the bearings must and should be indicated in the description." (Brown's Boundary Control and Legal Principles, 4th Edition by Curtis M. Brown, Walter G. Robillard and Donald A. Wilson, page 99)
• "Two mathematical elements of a curve are all that are needed, although three are usually quoted. Radius, central angle (delta), and curve length are more often used than are chord, middle ordinate, tangent, degree of curvature, or external distance." (Evidence and Procedures for Boundary Location, 5th Edition by Walter G. Robillard, Donald A. Wilson and Curtis M. Brown, page 447)
• "To define a curve in a description, at least two elements of the curve must be stated, and in addition (1) the relationship of the curve to the previous line, (2) the direction of the curve, and (3) the direction of travel of the curve must also be stated." (Brown's Boundary Control and Legal Principles, 4th Edition by Curtis M. Brown, Walter G. Robillard and Donald A. Wilson, page 110)
• "In description work, at least five elements are necessary to determine a curve:
  
  1 and 2. The elements of dimension (R & L; etc.)
  3. The direction of curvature (concave to SE; convex to W - convex rarely used).
  4. The direction of extension (travel) along the curve (Ely; Sly).
  5. The relation of the curve to the next preceding course (or curve) (tangent, compound, or radial bearing or beginning of curve, etc.).
  
  Optional additions to the five elements may include one or more dimension elements (central angle or angle of arc, tangent, chord bearing and/or length, etc.); relation of the curve to the next succeeding course or curve; any other data for clarity or interpretation. It is evident that the additions must be precisely consistent with the necessary elements given.
  
  In reciting such additions, name them in the order of intended superiority so that any inconsistency may be properly analyzed; for example: if length is recited prior to central angle even though calculated therefrom, it will probably prevail over the angle, while if the angle is first stated, the weight of probability tends toward the angle." (see Land Survey Descriptions by Wm. C. Wattles, 1956 p. 16)
• "a radial bearing to or from the 'center of said curve' is a bearing of the radial line passing through the midpoint of the arc." (see Land Survey Descriptions by Wm. C. Wattles, 1956 p. 16)
  • Problem, which of the two circles is being used with the radial bearing line and distance, see Definition of Radial Line
• "Although the bearing of a radial line on a map may be shown in either direction (N 10° E, S 10° W), the description should always recite the proper direction conformable with the context; the extension of a radial line is correctly from the center of the circle to the circumference." (see Land Survey Descriptions by Wm. C. Wattles, 1956 p. 18)
• "The bearings of radials (unless otherwise definitely stated) are expressed in a direction from the center of the circle to its circumference. The radial line stops at the circumference of its circle. If you wish to follow a radial line beyond that, you must use the expression, 'along the prolongation of said radial line...'" (Writing Legal Descriptions in Conjunction with Survey Boundary Control by Gurdon H. Wattles, page 4.26)

Glossary of Deed Terms

• Concave - the inside of a curve; toward the center of the circle
  • "The concavity direction of a curve is that of the direction of the center of the circle of said curve from the mid-point of the arc described; a described segment of a record curve may be concave to the Ease, while the whole of the record curve may be concave to the North. Fig. 5." (see Land Survey Descriptions by Wm. C. Wattles, 1956 p. 17)
  • "...direction of the concavity of a curve which is based on the bearing of a line passing through the midpoint of the arc toward the center of that circle. If it is near the bearing between two 'ly directions (e.g. norhterly, northeasterly, etc.) either one can be used or both can be expressed." (Writing Legal Descriptions in Conjunction with Survey Boundary Control by Gurdon H. Wattles, page 4.11)
• Radial or Radial Bearing - a radial line is any straight line extending from the center of a defined circle to the circle's circumference. A radial bearing is the direction of a given radial line. On plats the word radial next to a bearing indicates that that line is radial from the center of the given circle.
  • The radial bearing line and distance will give you two circles which can intersect the point. Problem is most legal descriptions, unknown if the surveyor is describing the arc by going from the center of circle to the circle's circumference or vise-versea from the circle's circumference to the center of the circle. Need another piece of information about the arc which is the concave direction. With the concave direction, you can easily identify which of the two circles are being used to define the arc in the legal description.
  • Radial Bearing Drawing - radial-line-bearing.dwg
  • Radially or in other words at right angle to. "...distance is measured at right angles, or radially..." (Writing Legal Descriptions in Conjunction with Survey Boundary Control by Gurdon H. Wattles, page 4.12)
  • ArcMap COGO Toolbar -> Curve -> Radial direction wants the radial bearings from the curve/circumference of the circle to center of the circle. So you might need to enter the opposite bearing direction. For example, my legal description gives a bearing of N45-15-7E from the center of the circle/curve to the circumference of the curve. When I enter this curve into ArcMap, I want to use bearing S45-15-7W.
• Thence - from that place; the following course is continuous from the one before it.
• Brown's Boundary Control and Legal Principles, 4th Edition by Curtis M. Brown, Walter G. Robillard and Donald A. Wilson, - Glossary of Deed Terms pages 374-400)

Definition of Curves

• 
• CHORD - also known as the Long Chord, LC. "is that segment of a straight line which is intersected by two points on a curve, or, in other words, the straight line distance between the two ends of a segment of arc." (Writing Legal Descriptions in Conjunction with Survey Boundary Control by Gurdon H. Wattles, page 4.21)

Aliquot Descriptions

• "...an aliquot description is a perfect description. According to federal law the least aliquot description available (or legal) is a quarter-quarter or one-sixteeth or 40 acres, according to the GLO survey. Yet many individuals may describe a section as small as a 1/64 or 1/256 or even smaller. It must be remembered that these boundaries are invisible and set by law as being a direct proportion, without a remainder." (see Brown's Boundary Control and Legal Principles, 4th Edition by Curtis M. Brown, Walter G. Robillard and Donald A. Wilson, page 102)

Legal Description and Figure

• "Thence from a tangent line bearing N 38° 13' E, northeasterly 60.00 feet along a curve concave to the southeast having a radius of 100.00 feet to the beginning of a reverse curve concave to the northwest having a radius of 60.00 feet; thence northeasterly 40.00 feet along said curve." (Writing Legal Descriptions in Conjunction with Survey Boundary Control by Gurdon H. Wattles, p. 4.25)
  
  WritingLegalDesc-Fig32a.dwg
• "If the line previous to the curve had already been cited, it would be unnecessary to repeat the bearing because it would be properly assumed that the curve was tangent unless otherwise stated."
  
  "Thence from a tangent line bearing N 29° 40' E, easterly 60.00 feet along a curve concave to the south having a radius of 60.00 feet to the cusp of a curve concave to the southeast having a radius of 50.00 feet, to which point of cusp a radial of the last mentioned curve bears N 23° 15' W; thence southwesterly 40.00 feet along said curve." (Writing Legal Descriptions in Conjunction with Survey Boundary Control by Gurdon H. Wattles, p. 4.25)
  
  
  WritingLegalDesc-Fig32b.dwg

Writing Legal Descriptions

• "Your slogan should be, 'Concise Clarity Without Ambiguity.' Do not use time or space for superfluous words, but, on the other hand, do not omit words or phrases that are necessary. Ask yourself the question 'Will the omission of these words change the meaning?' or 'Will the use of these additional words add to or subtract from the actual meaning of the whole phrase?'" (Writing Legal Descriptions in Conjunction with Survey Boundary Control by Gurdon H. Wattles, p. 11.2-3)
• Description of land by metes and bounds in a deed should always contain the following information in addition to the recital:
  1. Point of commencement (POC). This is an established reference point such as a corner of the PLSS or National Spatial Reference System (NSRS) monument to which the property description is tied or referenced. It serves as the starting point for the description.
  2. Point of beginning (POB)
  3. Definite Corners - provide a description of the point, for example a 1 inch iron pipe
     • Such corners are clearly defined points with coordinates if possible.
     • "The importance of permanent monuments to mark property is evident. In fact, some states require pipes, iron pins, and/or concrete markers set deep enough to reach below the frost line at all property corners before surveys will be accepted for recording. Actually, almost any suitable marker could be called for as a monument. A map attached to the description will contain a legend, which identifies all monuments." (Elementary Surveying, 13th Ediion by Ghilani and Wolf, p. 636)
  4. Lengths and directions of the property sides
  5. Names of adjoining property owners
  6. Areas
• (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 625 or Elementary Surveying, 13th Edition by Ghilani and Wolf, p. 637)

Example Legal Description

• 
• Reference the initial point meridian
  • "Being a portion of section 16, Township 22 South, Range 60 East, M.D.M, Clark County, Nevada, more particularly described as follows:"
• Point of Commencement
  • "Starting at the point of commencement, which is a 1 inch iron pipe at the southwest corner said section, township and range;"
• Point of Beginning
  • "thence north 87°52'37" East, along the south line of said section, a distance of 387.62 feet to a 1 inch iron pipe at the point of beginning of this description;"
• Lengths and directions of the property sides
  • "Thence continuing north 84°52'4" east, a distance of 460.45 feet to an 1 inch iron pipe;
  • "thence north 5°44'38" west, a distance of 213.77 feet to an 1 inch iron pipe;
  • which is the beginning of a curve, concave southwesterly having a radius of 150.00 feet; thence northwesterly, 211.30 feet along said curve through a central angle of 80.7123° to an 1 inch iron pipe;
  • thence north 86° 27' 23" west, a distance of 302.16' to an 1 inch iron pipe;
  • thence south 0° 36' 43" east, a distance of 407.29 feet to an 1 inch iron pipe which is the point of beginning."
• Areas
  • said parcel containing 3.67 acres, more or less
  • side note, remember 1 acre = 43,560 ft²
• Boundary Survey Examples by Vern Little with VTN
  • metes and bounds description for Golden 180 Access in Mohave County Arizona
  • metes and bounds description for Hawk Springs Road in Las Vegas Nevada
  • block and lot description for Northern Terrace at Providence - Unit 4 in Las Vegas NV
  • coordinate values description for Military Operations Area (MOA) Desert NV in Nevada
  • aliquot parts for Township 18 South and Range 64 East

Experts at Writing Legal Descriptions

• Kay Adams, retired, former County Surveyor for Clark County. Contact Calvin Black (voice: 804-2020, email: cblack@gcwallace.com)

Global Navigational Satellite Systems (GNSS)
Global Positioning Systems (GPS)

GNSS/GPS Overview

• "It was developed by the Department of Defense for military use; however, it has been adapted for a wide range of civilian navigational needs." (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanazfama and Kissam, ISBN-13 978-0-13-500037-3, p. 59)
• "Radio signals transmitted by orbiting earth satellites can be used to determine the horizontal coordinates, as well as the elevation, of any point on the earth's surface. A small portable antenna receiver and power source are set up over the survey station to track the radio signals." (Surveying Fundamentals and Practices, 6th Edition by Nathanson, Lanazfama and Kissam, ISBN-13 978-0-13-500037-3, p. 168-9)
• "Global geodetic applications require three different surfaces to be clearly defined. The first of these is the Earth’s topographic surface. This surface includes the familiar landmass topography as well as the ocean bottom topography. In addition to this highly irregular topographic surface, a definition is needed for a geometric or mathematical reference surface, the ellipsoid, and an equipotential surface called the geoid." (Department of Defense World Geodetic System 1984, p. 3-1)
  • 

Earth’s topographic surface - Orthometric Height (NAVD 88)

• The height between the geoid and a point on the Earth's topographic surface measured along the the plumb line (see Introduction to Geodetic Vertical Datums by Dave Doyle)
• H = orthometric height (NAVD88)
• This is the heights/elevations in which water runs downhill,
• don't get this value from GPS observations, get little h which is the Ellipsoidal Height
• 

Ellipsoid

• Elevation from the GPS unit
• "A spheroidal (ellipsoidal) vertical coordinate system (VCS) defines heights that are referenced to a spheroid of a geographic coordinate system. A Global Positioning System (GPS) unit natively reports heights relative to the World Geodetic System of 1984 (WGS84) ellipsoid. An onboard geoid model in the GPS unit converts the ellipsoidal heights to gravity-related elevations. A spheroidal height is a geometry quantity and does not have a physical sense, as a geographic coordinate system's spheroid may fall above above or below the actual earth surface. Spheroidal heights for an area may not reflect movement due to gravity, that is, the flow of water. Water can run uphill when working with spheroidal heights." (ESRI ArcGIS Vertical Datums)
• mathematical model of the size and shape of the earth
• Ellipsoid GRS80
• Principal Reference Ellipsoids in the U.S.A.
  • Datum, Heights and Geodesy by Daniel R. Roman and Geoid Surfaces and Theory See Presentations by the NGS Geoid Team
  • North American Datum of 1983 (NAD 83)
    • Many versions. The newer versions provide XYZ (lat, long and ellipsoid height)
    • Uses a Geodetic Reference System of 1980 (GRS-80) ellipsoid shell which was adopted by the International Association of Geodesy (IAG)
      • Geodetic Reference System 1980 by H. Moritz - "The Geodetic Reference System 1980 has been adopted at the XVII General Assembly of the IUGG in Canberra, December 1979,..."
      • "The equatorial radius a is the semimajor axis of the meridian ellipse" a = 6378137 m
      • "...the semiminor axis will be denoted by b. b = 6356752.3141 m
      • f = 0.003 352 810 681 18 flattening
    • ESRI supports the new datum of NAD 83(NSRS2007) for the United States see ESRI Article ID 34374 Does ESRI support the new datum NAD 83(NSRS2007) for the United States?
    • Coordinates compatible with GPS observations
    • system hasn't changed over time
    • the origin of the 3D cartesian system located at Earth's center of mass (geocenter)
    • Background
      • Reference Systems: Part 2: The Evolution of NAD 83, Professional Surveyor Magazine - February 2000. Dr Richard A. Snay and Tom Soler, Dr.
      • Reference Systems: Modern Terrestrial Reference Systems Part 1, Professional Surveyor Magazine - December 1999. Dr Richard A. Snay and Tom Soler, Dr.
  • North American Datum of 1927 (NAD 27)
    • Regional ellipsoid - not global
    • superseded by NAD 83
  • World Geodetic System of 1984 (WGS 84)
    • This is both a datum and an ellipsoid model which people find confusing.
    • "...GPS data always uses the WGS-84 coordinate system..." (Trimble Mapping & GIS Customer FAQs)
    • What is WGS 84?
    • Developed by NGA (formerly the National Imagery and Mapping Agency (NIMA) which was formerly the Defense Mapping Agency (DMA))
    • several versions since first introduced based on GPS week
    • very similar to the evolution of the ITRF models
    • essentially the same GRS-80 shell but a different geocenter
    • " WGS 84 uses an ellipsoid adopted by the National Imagery and Mapping Agency (NIMA, formerly the Defense Mapping Agency)" Reference Systems: Modern Terrestrial Reference Systems Part 1, Professional Surveyor Magazine - December 1999. Dr Richard A. Snay and Tom Soler, Dr.
    • offset is nearly 2.2 meters from NAD 83
    • WGS 84 (G730) and WGS 84 (G873) "where the ‘G’ indicates these coordinates were obtained through GPS techniques and the number following the ‘G’ indicates the GPS week number when these coordinates were implemented in the NIMA precise GPS ephemeris estimation process. The dates when these refined station coordinate sets were implemented in the GPS Operational Control Segment (OCS) were 29 June 1994 and 29 January 1997, respectively." (Department of Defense World Geodetic System 1984, p. xi)
    • Defining Parameters
      • semi-major axis, a = 6378137.0 meters same as the GRS 80 Ellipsoid (Department of Defense World Geodetic System 1984, p. 3-1)
      • semi-minor axis, b = 6356752.3142 meters (Department of Defense World Geodetic System 1984, p. 3-7) In GRS-80 the value of b = 6356752.3141 m (difference in 0.0001 meters from WGS 84)
      • flattening values, 1/f = 298.257223563 (Department of Defense World Geodetic System 1984, p. 3-1)
    • Ordnance Survey - World Geodetic System 1984 (WGS84)
    • Google Earth uses WGS84 Datum
  • International Terrestrial Reference System (ITRS)
  • 
• "Because the Earth is slightly flattened at the poles, a sphere won't work. A flattened sphere, which is called an ellipsoid, is used to represent the geometric model of the Earth." (Vertical Datums, Elevations and Heights)
• "...the earth's surface is approximated in size and shape by the geometric surface that is formed by rotating an ellipse about its smaller axis (Figure 1). The generated surface is termed an "ellipsoid of revolution" or simply ellipsoid. The ellipsoid's geometric center should be located at the origin of the 3D cartesian system, and its axis of radial symmetry (semi-minor axis) should coincide with the cartesian z-axis of the selected terrestrial reference frame. The size and shape of the rotated ellipse may be completely specified using two parameters: the length of its semi-major axis, usually denoted a, which approximates the distance from the geocenter to a point on the equator (approximately 6,378 km); and the length of the semi-minor axis, denoted b, which approximates the distance from the geocenter to the North Pole. The value of b is about 0.3% shorter than a. The fact that a is longer than b is a consequence of the force imparted by Earth's rotation causing our home planet to bulge outward around its equator. Often, instead of b, the ellipsoid's flattening, f = (a - b)/a, is used." Reference Systems: Modern Terrestrial Reference Systems Part 1, Professional Surveyor Magazine - December 1999. Dr Richard A. Snay and Tom Soler, Dr.
• Ellipsoid Model
• h = Ellipsoidal Height (NAD 83)
• 
• 
• Parameters for commonly used Ellipsoids
• Long Geodesics on the Ellipsoid by H. F. Rainsford (LongGeodesicsOnTheEllipsoid-HFRainsford.pdf) downloaded from Springerlink.com
• Direct and Inverse Solutions of Geodesics on the Ellipsoid with Application of Nested Equations by T. Vincenty. Survey Review XXII, 176, April 1975 (SurveyReviewApril1975-DistanceOnEllipsoid.pdf)

Geoid

• Level Surface. "A curved surface that at every point is perpendicular to the local plumb line (the direction in which gravity acts). Level surfaces are approximately spheroidal in shape. A body of still water is the closest example of a level surface. Within local areas, level surfaces at different heights are considered to be concentric. Level surfaces are also known as equipotential surfaces since, for a particular surface, the potential of gravity is equal at every point on the surface.
  Geoid. A particular level surface that serves as a datum for elevations and astronomical observations." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 73-4)
• "...the geoid is an equipotential gravitational surface located approximately at mean sea level, which is everywhere perpendicular to the direction of gravity. Because of variations in the Earth's mass distribution and the rotation of the Earth, the geoid has an irregular shape." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 522)
• "The geoid is defined as the surface of the earth's gravity field, which is approximately the same as mean sea level. It is perpendicular to the direction of gravity pull. Since the mass of the earth is not uniform at all points, and the direction of gravity changes, the shape of the geoid is irregular." (ESRI ArcGIS Desktop 10 - The geoid, ellipsoid, spheroid and datum, and how they are related)
• Geoid09 is based on the newer NAD83 datum (lat, long, ellipsoid height) which is based on the GRS80 ellipsoid.
• Geoid09 surface is just the height difference between the Geoid and the ellipsoid
• National Geodetic Survey (NGS) GEOID09 homepage
  • The Geoid09 and NAD83 ellipsoidal height are tied together, if you try to use the USGG2009 geoid model, will be more than a meter off.
  • GEOID09 geoid height calculator
  • GEOID09 PC Software Download
  • GEOID09 Data for Conterminous United States
    • ESRI TIFF image of the GEOID09 surface for Conterminous United States
      • GeoTIFF GEOID09conus.tif.zip or ESRI Image GEOID09conus.img.zip
      • Grid#1 GeoTIFF geoid09u01.tif.zip
      • Grid#2 GeoTIFF geoid09u02.tif.zip
      • Grid#3 GeoTIFF geoid09u03.tif.zip
      • Grid#4 GeoTIFF geoid09u04.tif.zip
      • Grid#5 GeoTIFF geoid09u05.tif.zip
      • Grid#6 GeoTIFF geoid09u06.tif.zip
      • Grid#7 GeoTIFF geoid09u07.tif.zip
      • Grid#8 GeoTIFF geoid09u08.tif.zip
    • Procedure to create an ESRI GRID from the GEOID09 data
      1. Download GEOID09 data in ASCII format
         • GEOID09 ASCII grid files for the Entire CONUS and individual Grids, GEOID09_conus_and_grids.zip
         • GEOID09 ASCII grid files with the ESRI GRID header, GEOID09_conus_and_gridsESRI.zip
      2. Read the GEOID09 Readme file
         • File Structure, first one line header info
           • SLAT: southernmost latitude in whole degrees minus sign (-) for South latitudes
           • WLON: westernmost longitude in whole degrees EAST
             • Note, ESRI ArcGIS projections like longitude between +-180°, so for North America, calculate the west longitude by subtracting 360°
             • Example, if longitude is in whole degrees EAST = 230°, then the west longitude is 230° - 360° = -130°
           • DLAT: distance interval in latitude in whole degrees (point spacing in E-W direction)
           • DLON: distance interval in longitude in whole degrees (point spacing in N-S direction)
           • NLAT: number of rows (starts with SLAT and moves northward DLAT to next row)
           • NLON: number of columns (starts with WLON and moves eastward DLON to next column)
           • IKIND: always equal to one (indicates data are real*4)
         • The GRID is written bottom to top which is flipped from what ESRI GRID wants
           • After this one line header, the data follow. The first row represents the southernmost row of data with the first data point being in the SW corner. The row is NLON values wide spaced at DLAT intervals, and then increments to the next row which is DLAT to the north. This continues until the last row where the last value represents the NE corner. The easternmost longitude is = WLON + (NLON - 1) * DLON, while the northernmost latitude is = SLAT + (NLAT - 1) * DLAT.
      3. Unzip and Edit the header file of the GEOID09 data file
         • Use a text editor like UltraEdit
         • Replace the first one line header with the ESRI GRID format
           24.000000000000 230.00000000000 1.6666666666667D-02 1.6666666666667D-02 1081 1141 1 -39.9743 -39.9936 -40.0128 -40.0320 -40.0512 -40.0704 -40.0896 -40.1089
         • ESRI ASCII raster format
         • ESRI GRID ASCII Format (.txt or .asc) for CONUS Grid #5
           NCOLS 1141 NROWS 1081 XLLCENTER -130.00000000000 YLLCENTER 24.000000000000 CELLSIZE 0.1666666666667E-01 NODATA_VALUE 1 -39.7345 -39.7579 -39.7802 -39.8005 -39.8208 -39.8391 -39.8564 -39.8737
         • ESRI GRID ASCII Format (.txt or .asc) for all CONUS
           NCOLS 4201 NROWS 2041 XLLCENTER -130.00000000000 YLLCENTER 24.000000000000 CELLSIZE 0.1666666666667E-01 NODATA_VALUE -9999 -39.7345 -39.7579 -39.7802 -39.8005 -39.8208 -39.8391 -39.8564 -39.8737
      4. Import ASCII file to Raster using ESRI ArcGIS - ArcToolbox
         • Open ESRI ArcMap application
         • Open the ArcToolbox
         • Search for the ASCII to Raster tool or navigate to Conversion Tools -> To Raster -> ASCII to Raster
         • Use an Output data type of Float. Note, unknown how to change the precision and scale of the cell values representing the Geoid Height in meters
         • ArcGIS Help - An overview of the To Raster toolset
         • ArcGIS Help - ASCII to Raster (Conversion)
      5. Flip the Grid
         • ESRI Help - Flip
         • Remember, ESRI GRID wants the ASCII data in a top to bottom format so we need to flip the ESRI GRID
         • Search for FLIP in ArcToolbox or navigate to Data Management Tools -> Projections and Transformations -> Raster -> Flip
         • ArcGIS Help - Flip (Data Management)
      6. Assign the WGS 84 Lat/Long Geographic Coordinate system to the ESRI GRID
         • Search for Define Projection in ArcToolbox or navigate to Data Management Tools -> Projections and Transformations -> Raster -> Define Projection
         • Unknown what to assign the vertical projection
         • ArcGIS Help - Define Projection (Data Management)
      7. Export to GeoTIFF
         • Search for Raster To Other Format (multiple) in ArcToolbox or navigate to Conversion Tools -> To Raster -> Raster to Other Format (multiple)
         • This creates four files (.tif, .tif.xml, .aux, and .rrd)
         • ArcGIS Help - Raster to Other Format (Conversion)
      8. Display in Google Earth
         • I'm having problems with Google Earth referencing the GeoTIFF file correctly. To manually place, use the following for Geoid09 CONUS
         • West = -130°
         • East = -59°59'
         • North = 58°1'
         • South = 24°
         • 
         • Output in Google Earth should look similar to this
           
         • Google Earth User Guide - Using Image Overlays and 3D Models
  • Where is the metadata for the GEOID09 Data? USGG2009 Readme
  • What is the header format for the ASCII file?
  • "The GEOID09 models are heights above the NAD 83 ellipsoid." (see How Prgram INTG Works in USGG2009 ReadmeWhat does this mean? Since all the values are negative does this imply the GEOID09 is below the ellipsoid? What does "NAD 83 ellipsoid" mean?
  • It appears the cell size is 1 minute, right?
  • What is the datum, WGS 84?
  • What is USGG2009 (gravity field model, developer first, regional, ITF00, measure only gravity doesn't include GPS or level loops, it is a geoid model)? Is this another name for GEOID09 (not global, uses GPS and orthmetric control points)? NAVD88 is not a geopotential surface
  • What is the difference between GEOID09 and Earth Gravitational Model (EGM2008) GIS Data (uses GRACE base model for USGG2009)
  • EGM2008 support: wgs84@nga.mil and 314-676-9127
  • GEOID09 support: 301-713-3242
    • Dr. Daniel Roman, National Geodetic Survey, NOAA, N/NGS6 301-713-3202x161 Internet: dan.roman@noaa.gov
    • Dr. Yan Ming Wang, National Geodetic Survey, NOAA, N/NGS6 301-713-3202x127 Internet: yan.wang@noaa.gov
• "It turns out that mean/average sea level (MSL) is a close approximation to another surface, defined by gravity, called the geoid, which in the true zero surface for measuring elevations. Because we cannot directly see the geoid surface, we cannot actually measure the heights above or below the geoid surface. We must infer where this surface is by making gravity measurements and by modeling it mathematically. For practical purposes, we assume that at the coastline the geoid and the MSL surfaces are essentially the same. Nevertheless, as we move inland we measure heights relative to the zero height at the coast, which in effect means relative to MSL." (Vertical Datums, Elevations and Heights)
• The Geoid is below the Ellipsoid in all 48 states. In Alaska and Hawaii, the Geoid is above the Ellipsoid. The distance between the Ellipsoid and the Geoid is call the Geoid Height and is always negative for the 48 states.
• N = Geoid Height (GEOID09) and is the greatest limiting factor in determining the orthometric height, H = h - N
• the Geoid is a model surface and the geoid height, N is accurate to 4 cm at the 95% confidence level for the 48 states.
• Equipotential surface in which gravity is normal (intersects at 90°) and most closely approximates mean sea level on a global basis.
• "The equipotential surface of the Earth's gravity field which best fits, in the least squares sense, mean sea level." (Definition from the Geodetic Glossary, Sept 1986) Can't see the surface or measure it directly. Modeled from gravity data. The Geoid most closely approximatates mean sea level on a global basis.
• "GEOID03 (United States) is a refinement of GEOID99, GEOID96, GEOID93 and GEOID90. GEOID03 is a geoid-elevation estimation model of the CONUS, referenced to the GRS80 ellipsoid. Thus, it enables mainland surveyors to convert ellipsoidal heights (NAD 83/GRS80) reliably to the more useful orthometric heights (NAVD88) at the centimeter level. GEOID03 was created from 14,185 points, including 579 in Canada and used updated GPSBMs that were not available for the previous geoid model (GEOID99). GEOID03 files are among the many services to be found at the NGS's Geodetic tool kit website at http://www.ngs.noaa.gov/TOOLS/" (Surveying with Construction Applications, 7th Edition by Barry F. Kavanagh, p. 235)
• Geoid models have been incorporated directly into GPS receivers
• NGA EGM96 WGS 84 Geoid Calculator contact Kurt Schulz (voice: 314-676-0793, email: kurt.j.schulz@nga.mil or schulzk@nga.mil)
• GPS on Bench Marks (GPSBM) used to make GEOID09 Excel Spreadsheet of points uses Ellipsoidal Reference Frame NAD83 (CORS96) 2002.0 for CONUS and vertical datum NAVD88
• "The GEOID03 model was developed to support direct conversion between NAD 83 GPS ellipsoidal heights and NAVD 88 orthometric heights." (GEOID03 Readme)
• "The GEOID03 models are heights above the NAD 83 ellipsoid." (GEOID03 Readme)
• "Since the sea surface conforms to the earth's gravitational field, MSL also has slight hills and valleys that are similar to the land surface but much smoother. However, zero elevation as defined by Spain is not the same zero elevation defined by Canada, which is why locally defined vertical datums differ from each other." ( Mean Sea Level, GPS, and the Geoid by Witold Fraczek)
• Orthometric Height, H is the distance from the Geoid surface to the ground. This is elevation we are trying to determine. "Geoid heights can be used to convert between orthometric heights (approximately mean sea level) and ellipsoid heights" (see NGA WGS 84 Geoid Calculator Read Me)
• Earth Gravitational Model 2008 (EGM2008) GIS Data
  • Software to Extract WGS 84 Geoid Undulations from Grid Files
    • Download the gridget_1min.exe program
    • Download the Raw data of 1x1-minute Geoid Undulation Grid in WGS 84
    • Enter limits (0-360 degrees): north south west east
      North = 37 South = 35 West = (360 - 116) = 244 East = (360 - 114) = 246
    • Output mode? 2 = Lat/Lon/Geoid Height
    • OUTPUT.DAT
    • Cellsize
      Degrees: 0.016667° = 1/60
      Meters: 1 second = 30 meters, so 1 min = 1800 meters (60sec x 30meters)
  • Joshua L Kennerly (email: joshua.l.kennerly@nga.mil, voice: 314-676-0861) created the 2.5 Minute Geoid Undulation ESRI Grid file
  • Global 2.5 Minute Geoid Undulations
• 
• 
• 
• 3D Geospatial Data by Eric Gakstatter
  • 
• NGS Contacts
  • Dru Smith, (301) 713-3222 x144, Dru.Smith@noaa.gov
  • Kendall Fancher, (540) 373-1243, Kendall.Fancher@noaa.gov (think he is the GIS Coordinator for NGS)
  • Eric Linzey, (301) 713-3198 x120, Eric.Linzey@noaa.gov (think he is a GIS cartographer with NGS, very helpful)
  • Brian Shaw, Brian.Shaw@noaa.gov
• How Accurately Can We Determine Orthometric Height Differences from GPS and Geoid Data? Journal of Surveying Engineering 129 (No. 1)
• On Geoid Models by James P. Reilly, Ph.D. (jpreilly@nmsu.edu or jpreilly@zianet.com), Point of Beginning 29 (No. 12):50. Oct 31, 2003
• ESRI ArcGIS Geoid help

Datums

• 1-D Vertical/Geopotential (Orthometric Height) - example NGVD 29, NAVD 88, Local Tidal)
• 2-D Horizontal (Latitude and Longitude) - example NAD 27, NAD 83 (1986)
• 3-D Geometric (Latitude, Longitude and Ellipsoid Height) - example NAD 83 (1993) and NAD 83 (2007)
• 4-D Geometric (Latitude, Longitude, Ellipsoid Height and Velocities) - example coordinates change with time such as ITRF00, ITRF008
• References
  • Introduction to Geodetic Vertical Datums by Dave Doyle on 2 March 2010

Google Earth

• Google Earth uses WGS84 datum

North American Vertical Datum

• NAVD88 is the predicted or realized surface of the geoid
• 2018 will re-define the NAD83 and NAVD88 datums to an absolute gravimetric geoid model along with Canada (see NGS 10 year plan). Thus will move away from passive benchmarks to a new vertical datum.
• 
• 
• Introduction to Geodetic Vertical Datums. The North American Vertical Datum of 1988 (NAVD88) and the National Geodetic Vertical Datum of 1929 (NGVD29) and their relation to tidal datums. This talk will also cover topics such as the National Spatial Reference System, types of heights, the Geoid model, gravity data and CORS and OPUS. Instructor: Dave Doyle (NGS Chief Geodetic Surveyor, 301-713-3178,dave.doyle@noaa.gov) Powerpoint Presentation or download from UNLV
• Guidelines for Establishing GPS-Derived Elliposid Height by David B. Zilkoski. NOAA Technical Memorandum NOS NGS-58.
• Point of Beginning 26, The GPS Observer: NAVD 88 GPS-Derived Orthometric Heights by David B. Zilkoski
  • Part 1, Feb 2001
  • Part 4, Sept 2001
    • 
• Father Point (Pointe-Au-Pere) Benchmark is maintained by the Canadian Hydrographic Service
  Canadian Hydrographic Service
  Department of Fisheries and Oceans
  615 Booth St.
  OTTAWA, Ontario K1A 0E6
  CANADA
  teleph: +1 (613) 995-4413
  telefax: +1 (613) 996-9053
  Benchmarks for Pointe-au-Pere (#2980) and it appears this station is for horizontal controle, not vertical which makes me feel there might be another benchmark called Father Point
  Dr. Mike Craymer (voice: 613-947-1829, email: craymer@nrcan.gc.ca)
  • "The tide gauge in Pointe-au-Pere (Father Point) was in operation from 1897 to 1983 before being transferred to Rimouski. The gauage in Rimouski is active since 1984." (see Canadian Spatial Reference System - Height Reference System Modernization)
  • "the geoid is a level surface; it does not coincide with Mean Sea Level. However, the geoid-datum will be near the Mean Sea Level on the east coast because the geoid will be selected such as it represents MSL at the tide gauge in Rimouski. This location is one of the constraints for CGVD28 and the only constraint for NAVD88 (US vertical datum)." (Natural Resources Canada (NRCan) - Canadian Spatial Reference System - Height Reference System Modernization FAQ - Does the geoid-based datum represent mean sea level better than the levelling-based datum CGVD28?)
  • Canada's new vertical datum "...is defined by the equipotential surface that coincides with mean water level at the tide gauge in Rimouski. The mean water level in Rimouski is defined such as the geoid heights (N) at benchmarks in the Rimouski/Pointe-au-Pere area are equal to the difference between NAVD88 orthometric heights and ellipsoidal heights: N_NAD83(CSRS) = h_NAD83(CSRS) - H_NAVD88 in the Rimouski/Pointe-au-Pere sector. Thus, the new vertical datum for Canada will have basically the same reference system as NAVD88." (Canadian Spatial Reference System - Height Reference System Modernization FAQ - Why a new name for the vertical datum?)

Ephemerides - Alamanacs containing data on the position of the sun and stars verse time

• U.S. Bureau of Land Management maintains ephemeris of the sun and Polaris at www.cadastral.com
• 2008 Sokkia Celestial Observation Handbook and Ephemeris (Elgin, Knowles & Senne, Inc. or download from UNLV 2008EPHEM.pdf)

Selective Availability (SA)

• "Selective Availability (SA) was an intentional degradation of public GPS signals implemented for national security reasons. At the direction of the President, SA was discontinued in May 2000 to make GPS more responsive to civil and commerical users world wide. The U.S. Government has no intent to use SA again." ( National Executive Committee - Selective Availability)

NGS Data Sheet

• NGS Data Sheets
  • Permanent IDentifier (PID) = station name for the control point which consists of two upper case letters followed by four digits, for example AB1098 (see What is a PID???)
  • PID = GR1938 and Designation/Name = HAZE (NGS Datasheet is http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=GR1938
    copy of the NGS Datasheet (NGS-Datasheet-PID-GR1938.pdf)
  • "The NGS makes complete descriptions of all its actual NGS horizontal control stations available to surveyors. As an example, a partial listing from an acutal NGS horizontal control station description is given in Figure 19.9 [PID=LZ1878 and Designation/Name=Hayfield NE 1974]. These descriptions give each station's general placement in relation to nearby towns, instructions on how to reach the station following named or numbered roads in the area, and the monument's precise location by means of distances and directions to several nearby objects. The station's specific description, such as, 'a triangulation disk set in drill hole in rock outcrop,' is given, along with a record of recovery history. Data supplied with horizontal control-point descriptions include the datum(s) used and the station's geodetic latitude and longitude. Also given are the state plane coordinates, convergence angle and scale factor, UTM coordinates, and approximate elevation and geoidal height (in meters)." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 543-4)
  • PID=AC3363 and Designation/Name = 872 3747 F TIDAL
  • 
• NGS ShapeFiles Retrieval Page
  • Nevada Survey Control Points shapefile NV.ZIP
    • LAST_COND = Last recovered condition of the mark.
      • blank/no value
      • DESTROYED
      • FIRST OBSERVED
      • GOOD
      • MARK NOT FOUND
      • MONUMENTED
      • POOR
      • SEE DESCRIPTION
• Metadata - Horizontal and Vertical Geodetic Control Data for the United States
• NOAA Tides & Currents - Bench Mark Data Sheets

Geometry of Observed Satellites

• 
• "As noted previously, by employing least squares in a GPS solution, the effect of satellite geometry can be determined. In fact, before conducting a GPS survey, the number and positions of visible satellites at a particular time and location can be evaluated in a preliminary least-squares solution to determine their estimated effect upon the resulting accuracy of the solution. This analysis produces so-called Dilution of Precision (DOP) factors.... Obviously, the lower the value for a DOP factor, the better the expected precision in computed positions of ground stations. If the preliminary least-squares analysis gives a higher DOP number than can be tolerated, the observations should be delayed until a more favorable satellite constellation is available." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 346)
• "The DOP factors that are of most concern to surveyors are PDOP (dilution of precision in position), HDOP (dilution of precision in horizontal position), and VDOP (dilution of precision in height). For the best possible constellation of satelites, the average value for HDOP is under 2 and under 5 for PDOP. Other DOP factors such as GDOP (dilution of precision in geometry) and TDOP (dilution of precision in time) can also be evaluated, but are generally of less significance in surveying." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 346)
• PDOP = Positional Dilution of Precision
  • Acceptable value 6 or less (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 347)
• HDOP = Horizontal Dilution of Precision
  • Acceptable value 3 or less (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 347)
• VDOP = Vertical Dilution of Precision
  • Acceptable value 5 or less (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 347)

Trimble TSC2

Using TSC2 with Sokkia SET6 Total Station

• Step 0: Configure Surveying Style. This only needs to be done one time on the TSC2
  • Using the TSC2 Survey Controller software, click Configuration -> Survey styles
  • click New
  • Name the style "SOKKIA-SET6"
  • Have the following options
    • Instrument
      • Manufacture: Sokkia
      • Model: SET (basic)
      • Baud rate: 1200
      • Parity: none
      • HA VA status rate: Never
      • Measure Distance on face 2: checked
      • Edit Instrument Precisions: No
    • Topo point
    • Stakeout
    • Duplicate point tolerance
    • Laser Rangefinder
• Step 1: create a new job
• Step 2: select surveying style
  • click Survey icon on the main survey controller homepage.
  • then click the survey style: "SOKKIA-SET6"
  • Station Setup
    • this will start the connection between the TSC2 and the SET6 total station. For some reason it just says "connecting to total station"
  • Station Setup Plus
  • Resection
  • Refine

How to load the latest Geoid Model into the Trimble TSC2

• Video - TrimbleTSC2-LoadGeoid.html
• Step 1: visit Trimble Geomatics Office Support website to find the latest Geoid for conterminous United States (CONUS)
  • download this Trimble format .ggf file for the Geoid 09 Combined CONUS
  • note — The files used by the Geoid Grid model are a Trimble proprietary format. To convert third-party grid files (such as those distributed by DMA) to the Trimble grid file format, you need a separate utility program called mkgrid.exe. Contact your Trimble dealer for details. (Trimble Business Center - Coordinate System Manager Help file)
  • Trimble Grid Factory utility to create subgrids from existing grids or to combine multiple existing grids into a single grid. v1.41-GridFactory.exe
• Step 2: copy .ggf onto TSC2
  • Read the Trimble Survey Controller (TSC2) Help manual File management and Project folders on p. 28
  • copy .ggf to the Trimble Data folder on the TSC2

How to load the latest Geoid Model into Trimble Business Center

• 
• Step 0: visit Trimble Geomatics Office Support website to find the latest Geoid for conterminous United States (CONUS). Note Geoid09 file is 33 MB (G09US.ggf)
• Step 1: start Trimble Business Center and open Coordinate System Manager
  • Tools -> Coordinate System Manager
• Step 2: identify the GeoData directory
  • Identify the data directory using View -> Options on the Coordinate System Manager dialog box
  • default directory is C:\Documents and Settings\All Users\Application Data\Trimble\GeoData\
  • Ken_Joyce@trimble.com recommends using C:\Program Files\Common Files\Trimble\GeoData
  • 
• Step 3: copy downloaded Geoid file into GeoData directory
  • using Windows Explorer, copy G09US.ggf into C:\Program Files\Common Files\Trimble\GeoData or C:\Documents and Settings\All Users\Application Data\Trimble\GeoData\
• Step 4: Add the Geoid model
  • Open the Coordinate System Manager dialog box
  • click the Geoid Models tab
  • right click on blank area and select Add New Model...
  • give a name to the user-defined Geoid Grid, that is GEOID09 (Conus)
  • from the File name drop down, select G09US.ggf
  • Alternatively - click Edit -> Add Geoid Model... from the menu toolbar
    • 
• Step 5: should see the GEOID09 (Conus) in the Coordinate System Manager window
  • 
• Step 6: copy survey .job file from TSC2 into TBC project file
  • Getting an error message, even though the Geoid09 model is installed, TBC cannot find it and I don't see it in the Select Geoid Model drop down list.
  • I tried installing the Geoid in both directories, still cannot see it.
  • Option 1: try using the Geoid uploaded from TBC into TSC2 and see if that works on a newly created .job file. Problem might be how the Geoid was loaded into the TSC2.
    • 

Projections

Projections used in State Plane Coordinate Systems

• "To convert geodetic positions of a portion of the Earth's surface to plane rectangular coordinates, points are projected mathematically from the ellipsoid to some imaginary developable surface -a surface that can conceptually be developed or 'unrolled and laid out flat' without distortion of shape or size. A rectangular grid can be superimposed on the developed plane surface and the positions of points in the plane specified with respect to X and Y grid axes. A plane grid developed using this mathematical process is called a map projection.... Today, two of the most commonly used mapping projections are the Lambert conformal conic and the Transverse Mercator projections." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 580)

Types of Projections

• Map Projects by USGS

State Plane Coordinate System (SPCS)

• "...points couldn't be projected from the ellipsoid to developable surfaces without introducing distortions in the lengths of lines or the shapes of areas. However, these distortions are held to a minimum by selected placement of the cone or cylinder secant to the ellipsoid, by choosing a conformal projection (one that preserves true angular relationships around points in a small region), and also by limiting the zone size or extent of coverage on the Earth's surface for any particular map projection. If the width of zones is held to a maximum of 158 mi (254 km), and if two-thirds of this zone width is between the secant lines, distortions (differences in line lengths on the two surfaces) are kept to 1 part in 10,000 or less. The NGS intended this accuracy in its development of the state plane coordinate systems." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 581-2)
• Clark County uses StatePlane Coordinate- Nevada East Zone (NV-E) along with other local agencies (e.g. City of Las Vegas, Henderson, North Las Vegas, and so on)
• Map of all Stateplane coordinate zones is included with ArcMap, depending upon where you installed the program, e.g. C:\Program Files\ArcGIS\Reference Systems\usstpln83.shp (download zip of shapefiles from UNLV, usstpln83.zip - Geographic Coordinate System - GCS_WGS_1984)
• 
• State Plane Coordinate System of 1983 NOAA Manual NOS NGS 5 by James E. Stem
  • "A new figure of the Earth, the Geodetic Reference System of 1980 (GRS 80), which approximates the Earth's true size and shape, supplied a better fit than the Clarke 1866 spheroid, the reference surface used with NAD 27." (ibid p. 2)
  • "The ellipsoid that forms the basis of NAD 83, and consequently the SPCS 83, is identified as the Geodetic Reference System of 1980 (GRS 80). GRS 80 provides an excellent global approximation of the Earth's surface. The Clarke spheroid of 1866, as used for NAD 27 approximated only the conterminous United States. Because the geoid separation at point MEADES RANCH was assumed equal to zero, a translation exists between ellipsoids. The ellipsoid change is the major contributor of the coordinate shift from NAD 27 to NAD 83." (ibid p. 12)
• NAD 27 - U.S. coast and Geodetic Survey (USC&GS) Special Publication 235 - The State Coordinate Systems
  • Shapefile of NAD27 Zones (usstpln27.zip)
  • Shapefile of NAD83 Zones (usstpln83.zip)
  • The State Coordinate Systems (A Manual for Surveyors) older version but better quality (The State Coordinate Systems)
  • http://www.ngs.noaa.gov/PUBS_LIB/publication235.pdf
  • State Zone: Nevada East
  • Grid: Transverse Mercator
  • Central meridian = 115°35' (-115.583333°)
  • Scale Ratio = 1:10,000
  • Origin: Lat=34°45' (34.75°) Long=115°35'
  • False Easting x(ft)=500,000
  • False Northing y(ft)=0
  • x' of lines of exact scale (ft) = 295,700
• Fundamentals of the State Plane Coordinate Systems
• U.S. Coast and Geodetic Survey. Manual of Traverse Computation on the Transverse Mercator Grid by Oscar S. Adams, Senior Mathematician and Charles N. Claire, Associate Mathematician. GPO, Washington, DC, 1935. 199 pages. Special Publication No. 195.
• Publication of North American Datum of 1983 State Plane Coordinates in Feet in Nevada

• Geodesy for the Layman ( TM8358_1.pdf or download a copy from UNLV Geo4lay.pdf)
• TM8358.1: Datums, Ellipsoids, and Grid Reference Systems ( TM8358_1.pdf or download a copy from UNLV TM8358_1.pdf)

• GRS 80
  • Equatorial Radius/Semiaxis, a = 6,378,137 meters
  • Polar Radius/Semiaxis, b = 6,356,752.3 meters
  • Flattening, f = 1/298.257
  • "in computations if the ellipsoid is assumed a sphere, its radius is usually taken such that its volume is the same as the reference ellipsoid. It is computed from (a²b)^1/3. For the GRS80 ellipsoid, its rounded value is 6,371,000 meters." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 523)
• WGS 84
  • Equatorial Radius, a = 6,378,135 meters
  • Polar Radius, b = 6,356,750.5 meters
  • Flattening, f = 1/298.26
• Nevada East Zone Map Projectsion: A Working Manual, p. 53 and 374
  • Transverse Mercator Projection
  • Central meridian = 115°35' West
    • ESRI uses -115.583333333333300000 decimal degrees = -115°35'
  • Scale reduction = 1:10,000
    • ESRI uses a scale factor of 0.999900000000000010
    • "Lines of contact. Any single meridian for the tangent project. For the secant projection, two almost parallel lines equidistant from the central meridian...Accurate scale along the central meridian if the scale factor is 1.0. If it is less than 1.0, there are two straight lines with accurate scale equidistant from and on each side of the central meridian." (ESRI ArcGIS Transerve Mercator)
  • Origin (latitude) = 34°45' North
    • ESRI uses 34.7500 decimal degrees = 34°45'
  • Coordinates of Origin (meters): False Easting x=200,000 and False Northing y=8,000,000
  • "State plane coordinate systems are generally designed to have a scale error maximum of about 1 unit in 10,000. Suppose you calculated the Cartesian distance (using the Pythagorean theorem) between two points represented in a state plane coordinate system to be exactly 10,000 meters. Then, with a perfect tape measure, pulled tightly across an idealized planet, you would be assured that the measured result would differ by no more than 1 meter from the calculated one. The possible error with the UTM coordinate system may be larger: 1 in 2500." (Introducing Geographic Information Systems with ArcGIS, 2nd Edition by Michael Kennedy, p. 18)
  • Datum: NAD 1983 (Conus) (Mol) is used on the Trimble TSC2
• 
• 
  • GPS Course Lesson 6: Two-Coordinate Systems and Heights by Jan Van Sickle, Senior Lecturer
  • "...the projection of points from the Earth's surface onto a reference ellipsoid and finally onto flat maps..." (ibid)
  • 
  • Stateplane Coordinates in USA use Secant Projections to minimize distortion by providing 2 lines of intersection instead of one line with the Tangent case. Secant Projection intersect the ellipsoid at two areas and these two lines are of exact scale (also known as standard lines) to the ellipsoid.
  • 
  • Ellipsoidal lengths = geodetic distances
  • Lengths on the map projection surface = grid distances
  • Grid North is parallel to the Central Meridian. Convergence is the angle between Grid North and Geodetic North
    • 
• False Easting and Northing
  • False easting is a linear value applied to the origin of the x coordinates.
  • False northing is a linear value applied to the origin of the y coordinates.
  • False easting and northing values are usually applied to ensure that all x and y values are positive.
    • False easting and false northing adjustments by Margaret M. Maher
      • "False easting and false northing values are sometimes inserted into a projection file in order to make all the x- and y-coordinate values across the area of the data positive numbers. False easting and false northing values can also be used to adjust the position of the data in either the east-west or north-south direction in order to align the data.
        Making the false easting value in the projection file larger will adjust the position of the data to the west, moving the data to the left in the ArcMap display. Making the false easting value in the project file smaller will adjust the position of the data east, to the right in the ArcMap display.
        Adjustments to the false northing value in the projection file will move the data display north or south, though they are not as intuitive as the false easting adjustments. Making the false northing value in the projection file larger will move the data display south in the ArcMap window. Making the false northing value smaller will move the data display north in the ArcMap window.
        Keep these adjustments in mind while creating the custom projection file to align your data in ArcMap." (Lining Up Data in ArcGIS by Margaret M. Maher, p. 55, ISBN 978-1-58948-249-4)
    • "A constant E₀ is adopted to offset the N grid axis from the central meridian and make E coordinates of all points positive. Similarly, a constant N_b can be adopted to offset the E grid axis from the southern edge of the projection." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 587)
  • You can also use the false easting and northing parameters to reduce the range of the x or y coordinate values. For example, if you know all y values are greater than 5,000,000 meters, you could apply a false northing of -5,000,000.
  • ESRI ArcGIS Desktop 10 - Projection parameters
  • 
• False Northing - NAD27 vs NAD83
  • According to David Doyle with NGS, metadata is hard to obtain on current surveying work but was extremely difficult in the 1980s. So, the State of Nevada wanted to ensure when surveyors where working with the two different Datums (NAD27 and NAD83) that a surveyor could easily tell from the coordinate values, which Datum is being used. So the NAD83 coordinates have a 8,000,000 meters added to the Northing (Y) coordinate values.
  • NAD27 - Nevada East Zone uses a False Northing of 0 ft
  • NAD83 - Nevada East Zone uses a False Northing of 8,000,000 meters (26,246,666.66666666 feet)
  • Notice how the same data (city boundaries in Clark County NV) do not overlay, that is the NAD83 is shifted 8,000,000 meters north of the NAD27 layer
    • 
• Conversion from NAD83/27 to Geodetic/Geographic
  • NGS SPC to Geodetic
    • 
• Central Meridian (Longitude)
  • Notes from Earl F. Burkholder, PS, PE with Global COGO, Inc., Las Cruces NM 88003
    • Central Meridian (Longitude) is a north/south line and secant lines in a transverse Mercator projection are parallel to the central meridian. Problem is Longitude lines are not parallel because the all converge at the poles.
    • The easting of a secant line will vary slightly from the south end of the state to the north end.
    • secant line in state plane coordinates is always a constant distance from the central meridian.

• Map UTM Zones for lower-48 states
• 

How to draw the SPCS origin

• Step 0: download the World GeoReference Lines
• Step 1: Identify the SPCS Defining Parameters
  • If you have ArcGIS installed on your computer, view the projection file (.prg)
    C:\Program Files\ArcGIS\Coordinate Systems\Projected Coordinate Systems\State Plane\NAD 1983\NAD 1983 StatePlane Nevada East FIPS 2701.prj
  • Elementary Surveying, 12th Edition by Ghilani and Wolf, Appendix F (and definitions on p. 586) U.S. State Plane Coordinate System Defining Parameters
    • Geodetic Latitude, φ_P (Greek small letter phi)
    • Geodetic Longitude, λ_P (Greek small letter lambda)
    • False Easting, E₀
    • False Northing, N_b
    • Scale Factor at the Central Meridian, k₀
• Step 2: Create a shapefile using WGS84 geographic coordinates (e.g. GCS_WGS_1984)
  • Use ArcCatalog to create a new shapefile. Assign it the GCS_WGS_1984 projection
• Step 3: create gratitcules
  • Using an ArcMap edit session, add the line features using Absolute X,Y to enter the latitude and longitude values

Scale Factors

• scale factors move distances from the stateplane grid to the ellipsoid
• "After a distance has been reduced to its ellipsoidal equivalent, it must then be scaled to its grid equivalent. This is accomplished by multiplying the ellipsoidal length of the line by an appropriate scale factor." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 599)
• 
• Scale, Elevation, Grid, and Combined Factors Used in Instrumentation. Professional Surveyor Magazine - Feb 2006

Coordinate Systems (Geographic and Projected) in ArcMap

When adding data to ArcMap, will sometimes get a warning message "One or more layers is missing spatial reference information, Data from those layers cannot be projected"

• "If you add a layer that is in a projected coordinate system to ArcMap, and the coordinate system information is missing" will get that message. Much of the time this is not a problem. You can still display and work with this data as long as ArcMap does not need to project it on the fly. ArcMap will not be able, however, to align this data with data in a different coordinate system." [Ormsby 01, p. 340]

Map Projections

• Mathematical transformation of a model of the earth's shape (i.e. Oblate Spheroid) to a flat surface (grid). [Ormsby 01, p. 324]
• Can distort shape, area, distance, and direction
• Geographic Coordinates System (GCS)
  • based on a curved surface
    • Sphere - less accurate approximation of the shape of the earth
    • Spheroid - more accurate approximation of the shape of the earth (most widely used)
    • Geoid - most accurate model of the shape of the earth
  • a measurement of a location on the earth's surface expressed in degrees of latitude and longitude. Tend to have a "taffy-pull appearance" when displaying [Ormsby 01, p. 331]
  • GCS includes: angular unit of measure (e.g. degrees), prime meridian (i.e. line of zero longitude which passes through Greenwich England), and a datum (e.g. position of spheroid relative to the center of earth, typically use North American Datum of 1983 a.k.a. NAD83)
  • Latitude: horizontal lines (e.g. equator) and also known as parallels. Measurement values range from -90 to 90 degrees
  • Longitude: vertical lines, also known as merdians. Measurement values range from -180 to 180 degrees.
  • Degrees - 1/360th of a cirle
  • Minutes - 1/60th of a degree, or 60 minutes = 1 degree
  • Seconds - 1/60th of a minute, or 60 seconds = 1 minute
  • 
  • See ESRI Virutal Campus - Learning ArcGIS 9, Module 3 for more details
• Projected Coordinates
  • based on a flat surface
  • does NOT use spheriods, spheres, or geoids since these are approximations of the shape of the earth
  • also known as planar coordinates
  • a measurement of a location on the earth's surface expressed in a two-dimensional system that locates features based on their distance from an origin (0,0) along two axes.
• Map projections transform latitude and longitude to x,y coordinates in a projected coordinate system.
• Latitude and Longitude can located exact locations on the earth, but no uniform units of measurement (see figure on [Ormsby 01, p. 326])
• If all your GIS data is using the same coordinate system, don't have to worry about projections
• Empty data frames inherit the projection of the first layer added to it. [Ormsby 01, p. 333]
• On-the-fly Projections, [Ormsby 01, p. 328, 336]
• ArcMap determines if the coordinate system is geographic or projected by comparing the coordinates. Lat/Long values will be in the tens (Lat=36 degrees) and hundreds (Long=-115 degrees), where as Stateplane coordinates hundred thousand (e.g. x=800,000) and tens of million (y=26,750,000)[Ormsby 01, p. 340]
  • On-the-fly projections are less mathematically rigorous than permanent projections done using the ArcToolbox Projection Wizard. [Ormsby 01, p. 330]
  • On-the-fly projections are defined by the Layer Properties. Note this doesn't change the actual file. Projection only applied to data frame. [Ormsby 01, p. 330]
  • "... a coordinate system is a framework for locating features on the earth's surface using either latitude-longitude or x,y values."
  • Works well when the data has the same geographic coordinate system (GCS). [Ormsby 01, p. 329]
  • To transform the coordinate location of a CAD file using coordinate values in ArcMap, see ESRI Article Number 20860
• Projection info is assigned to the feature dataset, not the geodatabase. Note all feature classes in a feature dataset must have the same projection. Doesn't appear that all feature datasets need to have the same projection in a geodatabase. Remember a feature class can be contained in a feature dataset, which will ensure it has the same projection info, or can be a standalone feature class.
• ESRI software does not support vertical datums. Only reads the z-value as is, you must perform any pre-processing/corrections to the vertical data before entering into ArcGIS. Appears the projection metadata doesn't allow you to enter any additional z-value related data (for example NAVD88 datum, elevation units of feet, and so on).fs

How to Project Geodatabases and Shapefiles

• Projections in ArcMap
  • Can project the data frame, not the actual feature class, shapefile, or coverage.
  • Can export the layer with the same projection as the data frame, so in a sense your actually reprojecting the layer.
  • ArcMap will not project data on the fly if the coordinate system for the data set has not been defined.
  • Additional info, see ESRI Article ID 24893, How to identify an unknown coordinate system using ArcMap.
  • ESRI Article ID 20837, how to align vector data in ArcMap
• Projections in ArcCatalog
  • Can only define a projection for a layer, not reproject it.
  • Data frame will inherit the projection of the first layer added to it.
  • ArcCatalog: select a geodatabase feature, right mouse click to bring up the context menu, Properties -> Fields tab, select Shape, then at the bottom of that window, click the ellispe (...) and either Select or Import.
• Projections in ArcToolbox
  • Will reproject the layer permentently
  • ArcToolbox: Data Management -> Projections -> Project Wizard (shapefiles, geodatabase)
• Reference: see ESRI Article ID 21447 how to project shapefiles or geodatabase feature classes with the ArcToolbox Project wizard

Define a Shapefile's Projection

• Using ArcCatalog
  • Problem: metadata, spatial reference property says "unknown" or "assumed geographic" projection.
  • File -> Properties -> Fields tab: click Shape column. In Properties list below, select ellipses button to open the Spatial Reference Properties window. Click Select... button. Browse through Projected Coordinate Systems folder -> State Plane folder -> NAD 1983 (Feet) folder -> NAD 1983 StatePlane Nevada East FIPS 2701 (Feet).prj
  • Metadata should now say the projected coordinate system name.
  • Shapefile's coordinate system parameters are stored in the same location and name as the shapefile but with a .prj extension
  • see ArcGIS Desktop Help -> ArcCatalog -> Working with shapefiles -> Defining a shapefile's coordinate system
  • 
• Using ArcToolbox
  • ArcToolbox -> Data Management Tools -> Projections -> Define Projection Wizard (shapefiles, geodatabase). Then give same inputs as the "Using ArcCatalog" solution above.
  • see [Ormsby 01, p. 341-346]

Define a ArcInfo Coverage's Projection

Define a GeoDatabase feature class Projection

Common Coordinate Systems used in Clark County NV

• StatePlane Coordinate System (SPCS)
  • Projection used by local agencies (e.g. Clark County, City of Las Vegas, Henderson, North Las Vegas, and so on)
  • Map of all Stateplane coordinate zones is included with ArcMap, depending upon where you installed the program, c:\arcgis\arcexe83\Reference Systems\usstpln83.shp or C:\Program Files\ArcGIS\Reference Systems\usstpln83.shp (download shapefiles from UNLV, usstpln83.zip - Geographic Coordinate System - GCS_WGS_1984)
  • Clark County uses StatePlane Coordinate- Nevada East Zone (NV-E)
  • 
  • ArcGIS Resource Center - view of USSTPLN83.shp
• Universal Transverse Mercator, UTM
  • Earth is divided into 60 zones (each zone 6 degrees of longitude)
  • Origin for each zone is the Equator and its central meridian (3 degrees west and 3 degrees east). To eliminate negative coordinates, a false easting of 500,000 is applied
  • Typically used for statewide datasets
  • Map of all UTM zones is included with ArcMap, depending upon where you installed the program, c:\arcgis\arcexe83\Reference Systems\utm.shp or c:\Program Files\ArcGIS\Reference Systems\utm.shp (download shapefiles from UNLV, utm.zip - Geographic Coordinate System - GCS_WGS_1984) and overlay with the USA Counties Layer countyp020.zip from the National Atlas
  • Best way to show two datasets that are in different UTM zones, is to project one into the other zone.
  • State of Nevada uses UTM Zone 11
  • 
  • Margaret Maher (mmaher@esri.com) with ESRI Tech Support - specialize in Map Projections and Symbology
• Local/Surface Coordinates
  • Used extensively for small development projects by surveyors
  • referred to as ground distances by surveyors
  • different origin for each design project
  • To project into another coordinate system, need 2 points and have coordinate values in both systems.

Define Local/Surface Coordinate Projection in ArcMap

• Objective is to create a projection file so ArcMap can project on the fly from local/surface coordinates to stateplance coordinates. The projection file (.prj) will be similar to a shapefile file .prj file but for the AutoCAD .dwg, example anyfilename.dwg and anyfilename.prj (note cannot have any spaces in the filename for the .dwg and .prj files). Then ArcMap will automatically project the dwg.
• Most difficult step is determining the local/surface coordinate parameters
• ArcMap Data Frame Properties -> New -> Projected Coordinate System
• Projection name cannot contain spaces
• Custom Projection File options for 7 local/surface projections
  • Local
    • Parameters
      • False_Easting
      • False_Northing
      • Scale_Factor
      • Azimuth
      • Longitude_Of_Center
      • Latitude_Of_Center
    • Linear Unit = Foot_US
    • Datum is defined by Select... button under Geographic Coordinate System, select North America folder
      • North American Datum 1983.prj
      • North American 1983 HARN.prj (use if survey done to HARN accuracy)
      • North American 1983 (CSRS98).prj is for Canada
  • Hotine_Oblique_Mercator_Azimuth_Center
  • Hotine_Oblique_Mercator_Azimuth_Natural
  • Hotine_Oblique_Mercator_Two_Point_Center
  • Hotine_Oblique_Mercator_Two_Point_Natural
  • Rectified_Skew_Orthomorphic_Center
  • Rectified_Skew_Orthomorphic_Natural_O (has a rotation parameter)

Indepth Discussion on Projections

• Map Projection Overview
• Welcome to the Map Projection Home Page
• State Plane Coordinates vs. Surface Coordinates, Part 1
• State Plane Coordinates..., PDF version
• Understanding Map Projects by Melita Kennedy and Steve Kopp with ESRI.
• Online conversion between geographic coordinates to stateplane coordinates, NGS Geodetic to SPC. Input Lat/Long in Degrees Minutes Seconds (DMS). Use Zone 2701 for Clark County Nevada, also known as the Nevada East Zone. The output distance is in meters, to convert to U.S. Survey Foot use the ratio 1200m/3937ft.
• USGS Monument Data sheets use to find the lat/long, utm, and stateplane coordinate for monuments show on the USGS Quad maps. Obtain the quad names from c:\arcgis\arcexe82\Reference Systems\usgs24q.shp

Trimble Survey Controller - Software

Trimble Survey Controller - Geoid Model

• "The geoid is a surface of constant gravitational potential that approximates mean sea level. A geoid model or Geoid Grid file (*.ggf) is a table of geoid-ellipsoid separations that is used with the GNSS ellipsoid height observations to provide an estimate of elevation. The geoid-ellipsoid separation value (N) is obtained from the geoid model and is subtracted from the ellipsoid height (H) for a particular point. The elevation (h) of the point above mean sea level (the geoid) is the result. Note - For correct results, the ellipsoid height (H) must be based on the WGS-84 ellipsoid." ( Trimble Survey Controller HELP version 12.46, January 2010, p. 443-4)
  • 

Files

• Used to create the job files

Key in

Configuration

Survey

• FastStatic...
  • 
• PPK...
• RTK...
  • requires a radio link or cell phone wireless card between the transmitter at the base station and the receiver at the rover, and they both must be tuned to the same frequency. (GPS for Land Surveyor 2nd Edition by Jan Van Sickle, p. 230)
  • GPS Base stations in Las Vegas Valley
  • Requires a firmware update to the GPS receiver at the rover to enter the frequencies of the base stations.
  • Can only get to one base station at a time
  • It is best if the base station is within line of sight of the rovers.
  • "RTK is at its best when the distance between the base station and the rovers is less than 20 km, under most circumstances, but even before that limit is reached the radio data link can be troublesome." (GPS for Land Surveyor 2nd Edition by Jan Van Sickle, p. 231)
• RTK & infill...

Cogo

Instrument

GPS Survey

Tripod and Pole-Mounted Antenna Considerations

• "GPS antennas can be mounted directly to tripods via optical plummet-equiped tribrachs. All static survey occupations and base station occupations for all other types of GPS surveys require the use of a tripod. Care must be taken to center the antenna precisely and to measure the Antenna Reference Height (ARH) precisely.... The measured ARH (corrected or uncorrected) is entered into the receiver. When a lock has been established to the satellites, a message is displayed on the receiver display, and observations begin. If the ARH cannot be measured directly, then slant heights are measured. Some agencies measure in two or three slant locations and average the results. The vertical height can be computed using the Pythagorean theorem: ARH = √(slant height² - antenna radius²)" (Surveying Principles and Applications, 8th Edition by Barry Kavanagh, p. 265-6)

GPS Survey Planning

• GPS Field Notes
  • Date of observations (year, month, day and Julian day number)
  • Session identification
  • Station identification (name and number as provided by the project authority)
  • Receiver model
  • Serial numbers of receiver, antenna and data logger
  • Height of antenna phase center above the marker (to 1 mm) and all measurements taken to derive that height (a sketch depicting the procedure is also recommended)
  • Antenna offset from marker, if any (distance and azimuth)
  • Starting and ending time (UTC) of observations
  • General weather condition and changes, if any during the session
  • Detailed meteorological observations, if required
  • All problems or unusual behavior with equipment or satellite tracking
  • An obstruction diagram, showing any obstructions at elevations greater than 15° as seen from the antenna location, may also be added to the field log.
  • Guidelines and Specifications for GPS Surveys, p. 12
• GPS Field Log
  • Natural Resources Canada - Geomatics Canada - Geodetic Survey Division. GPS Positioning Guide
  • 
• Geometric Dilution of Precision (GDOP)
  • "GDOP of 7 or below is usually considered suitable for positioning - a value of 5 or lower is ideal." (Surveying Principles and Applications, 8th Edition by Barry Kavanagh, p. 260)

Kinematic GPS Methods

1. Real-Time Kinematic (RTK) mode
2. Post-Process Kinematic (PPK) mode

• "...a kinematic survey requires two receivers collecting observations simultaneously from a pair of stations with one receiver: the base, occupying a station of known position, and the rover collecting data on points of interest." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 391)

Real Time Kinematic (RTK)

• "Kinematic Surveys. As the name implies, during kinematic surveys one receiver, the rover, can be in continuous motion. This is the most productive of the GPS surveys, but is also the least accurate. The accuracy of a kinematic GPS survey is typically in the range of ±(1 to 2 cm + 2 ppm). This accuracy is sufficient for many types of surveys and thus is the most common method of surveying. Kinematic GPS is applicable for any type of survey that requires many points to be located, which makes it very appropriate for most topographic and construction surveys. It is also excellent for dynamic types of surveying, that is, where the observation station is in motion. The range of a kinematic survey is typically limited to the broadcast range of the base radio. However, real-time networks have made kinematic surveys possible over large regions." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 363)
• "The method of choice for a centimetre-accuracy site survey is RTK (Real Time Kinematic). RTK involves the use of 2 GPS receivers (stationary Base Station and a Rover) communicating together via a radio link. The base station must be located such that it will have a clear view of the sky and a continuous line-of-sight to the rover. The precision of the Rover position relative to the Base station is dependant on baseline-length so it is desirable to keep the baseline as short as possible (<10 km)." (Canadian Spatial Reference System - Site Survey using RTK)
• "Real-time differential surveys. Also known as real-time kinematic (RTK). Accuracies: 1 to 2 cm. Requires a base receiver occupying a known station, which then radio-transmits error corrections to any number of roving receivers, thus permitting them to perform data gathering and layout surveys in real time. All required software is on board the roving receivers. Dual-frequency receivers permit on-the-fly (OTF) reinitialization after loss of lock. Baselines are restricted to about 10 km. Five satellites are required. This, or similar techniques, is without doubt the future for many engineering surveys." (Surveying Principles and Applications, 8th Edition by Barry Kavanagh, p. 282)
• "For kinematic surveys, PDOP values should be less than four. Additionally, since high free electron counts in the ionosphere can affect GPS signals greatly, it is important to collect data only during periods of low solar activity. During periods of high solar activity, poor positioning results can be obtained with GPS. NOAA provides daily, three-day, and weekly forecasts of the space weather. In particular, GPS users should monitor the k-index values. GPS surveys should not be performed when the k-index is greater than 4. Both high PDOP values and high solar activity periods can be avoided with careful project planning." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 396)
  • Space Weather Prediction Center - Geomagnetic A and K indices from USGS Stations
  • NOAA Space Weather Forecasts
• Never do an RTK survey in float mode, always do an RTK survey in fixed mode

RTK - Community Base Stations

• Base radio mode: TT450s at 9600 bps
• "In North America and in other areas of the world, frequencies in the range of 150-174 MHz in the VHF radio spectrum, and from 450-470 MHz in the UHF radio spectrum, can be used for RTK transmissions. Typically, the messages are updated at the rover every 0.5-2 seconds. The data link for RTK requires a minimum of 2400 baud or higher for operation. However, it is typically much higher with a baud rate of typically 38,400." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 396)
• "The radio link used with RTK can limit the distance between the base receiver and rover(s) to under 10 km, or about 6 mi. As shown in Figure 15.4, this distance can be increased with more powerful transmitters, or through the use of repeater stations. A repeater station receives the signal from a transmitter such as the base radio and re-transmits it.... With low-power radios, line-of-sight between the transmitter and receiver is required." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 397)
• "In areas where cellular coverage is available, data modems can also be used to broadcast data from the base receiver to the rover." (Elementary Surveying, 12th Edition by Ghilani and Wolf, p. 397)

RTK Radio Configuration on Trimble TSC2

• Turn on the Trimble R8 receiver and TSC2 data collector
• Using Survey Controller software application on the TSC2, click the Configuration icon
• Under survey styles, click RTK
• Select Rover radio
• click connect button
• Select a radio frequency
• 

Post-Process Kinematic (PPK)

• "In post-processed kinematic (PPK) GPS surveys, the collected data is stored on the survey controller or receiver until the fieldwork is completed. The data is then processed in the office using the same software and processing techniques used in static GPS surveys. Data latency is not a problem in PPK surveys since the data is post-processed. Other advantages of PPK surveys are (1) that precise ephemeris can be combined with the observational data to remove errors in the broadcast ephemeris and (2) the base station coordinates can be resolved after the fieldwork is complete. Thus the base station's coordinates do not have to be known prior to the survey. The lack of data latency and use of a precise ephemeris results in a PPK survey having higher accuracies than that obtainable from the same RTK survey." (Elementary Surveying, 12th Edition, by Ghilani and Wolf, p. 396)
• "...epoch rate for data collection is typically set to 1 sec." (Elementary Surveying, 12th Edition, by Ghilani and Wolf, p. 396)

UNLV Survey Points

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  • Raw Fast-Static GPS Observations: R8GNSS.kml and R8GPS.kml
• Map of survey points on UNLV campus CEE121-MapFieldPoints.pdf and pictures of the points CEE121-PicturesFieldPoints.docx
  • Used an assumed bearing of S 86° 45' 00" W for (W4 and W5), (E1-2 and E2-4) and (E2-4 and E2-3)
• Topo point data file of the area on the east side of the engineering building. This is the outcome of a lab exercise to help the students get a feel for collecting data points and preparing surface/topographic contour map. Obtained from Tom Barnes, PLS UNLVTopoLab-22Oct2008-EastsideTBE.txt
• UNLV Campus Topo from AeroTech (2007)
  • UNLV.dwg and
  • TopoImage-215.dwg
  • Black & White Aerial Photo - TopoImage-215.tif and TopoImage-215.tfw
  • Alternative Download: L:\Jeffery Jensen\GISdata\aerotech\AeroTech-UNLVCampus.zip
• Standard
  • Closed Traverse - measurement of the single and double angles should be within 20" minutes or less. If the off by more than 20" then remeasure the angle
  • Linear Error of Closure needs to 1:1500 or better

UNLV 2010 Survey Control by TRC

• TRC Party: Darrell Webb, Scott Hill PLS, and Jack Graham
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UNLV Benchmark

• Brass Cap Stamp
  • Title: Mon. B. East
  • Elevation = 2021.48 feet
  • State Plane Coordinate System (SPCS) Nevada East Zone NAD27 Units Feet, Area/Zone = 2701
  • Northing, N (Y) = 495137.956 feet
  • Easting, E (X) = 630828.541 feet
• Conversion from SPCS NV-E NAD27 to Lat/Long:
  Latitude (Y)=36°6'34.59307"
  Longitude (X)=115°8'25.50516"
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NGS Calibration Base Lines (CBL)

• Electronic Distances Measuring Instruments (EDMI)
• NGS National Geodetic Information Center - email: Steve.Breidenbach@noaa.gov, voice: 540-373-1243
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Receiver Independent Exchange (RINEX2)

• "In recent years, the NGS with cooperation from other public and private agencies has created a national system of Continuously Operating Reference Stations, also called the National CORS Network.... As of January 2007, there were 1221 CORS stations. These stations not only have their positions known to high accuracy, but they also are occupied by a GPS receiver that collects GPS data continuously. The collected data is then downloaded and posted on http://www.ngs.noaa.gov/CORS/. This information can be used as base station data to support roving receivers operating in the vicinity of the CORS station. The data is stored in a format known as Receiver INdependent EXchange (RINEX2). This format is a standard that can be read by all post-processing software." (Elementary Surveying, 12th Ed, Ghilani and Wolf, p. 374)
• GPS Data Share from LVVWD
  • RINEX data for the past 7 days is available at ftp://ftp.lvvwd.com/pub/GPS_Data/
  • nvca0910.rnx.zip where 091 is the day of the year out of 365 days.
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• Explanation of the contents of the RINEX2 data file