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    12 ACSM BULLETIN june 2007

    Surveyingsurveyingupclose

    tional lands acquired by the U.S. from Spain, France, and

    other Nations. Today, Americas public lands total aboutone-eighth of the land mass of the country. The PublicLand Survey System (PLSS) covers major portions of thirtysouthern and western states and is managed by the fed-eral Bureau of Land Management.

    Methods and instrumentsHistorically, angles and distances were measured using chainswith links of a known length, for instance a Gunters Chain, ormeasuring tapes made of steel or invar.

    Horizontal angles were measured using a compass, whichwould provide a magnetic bearing. This type of instrument waslater improved with telescopes with reticles for more precise

    sighting, giving rise to the theodolite. Vertical angles weremeasured with a transit (developed at the turn of the 19th cen-tury).

    The simplest method for measuring height is with an altimeterbasically a barometerusing air pressure as an indication of height.But for surveying, more precision is needed. Toward this end, avariety of means, such as differential levels, have been developed.Levels are calibrated to provide a precise plane from which differ-ences in height between the instrument and the point in questioncan be measured, typically by using a vertical measuring rod.

    As late as the 1990s the basic tools used in planar surveyingwere a tape measure (for determining shorter distances), a level(to determine height or elevation differences), and a theodolite (tomeasure angles) combined with triangulation. These instruments

    measured the distance and angles to an unknown point using amonument, a position with known location and elevation.

    The total station, a theodolite with an electronic distance mea-surement device (EDM) that can also be used for leveling whenset to the horizontal plane, replaced optical-mechanical deviceswith a fully electronic instrument with an onboard computerand software. Modern top-of-the-line total stations use a reflec-

    Definition

    Surveying is the technique and science of accurately determiningthe three-dimensional space position of points and the distancesand angles between them. These points are usually, but not exclu-sively, associated with positions on the surface of the Earth andare often used to establish land maps and boundaries for privateownership or government purposes.

    The basic principles of surveying have changed little overthe ages, but the tools used by surveyors have evolvedtremendously. Engineering, especially civil engineering,depends heavily on surveyors. Whenever there are roads,dams, retaining walls, bridges or residential areas to be built,surveyors are involved. They determine the boundaries of pri-vate property and the boundaries of various lines of politicaldivisions. They also provide advice and data for geographicalinformation systems (GIS), computer databases that contain

    data on land features and boundaries.Surveyors must have a thorough knowledge of algebra,

    basic calculus, geometry, and trigonometry. They mustalso know the laws that deal with surveys, property, andcontracts. In addition, they must be able to use high-techinstruments with accuracy and precision.

    Origins

    Surveying techniques have existed throughout much of record-ed history, beginning with ancient Egypt. Some of the turningpoints in surveying are: The establishment of the Egyptian land register (3000 BC).

    Under the Romans, land surveyors were recognized as aprofession; they developed the basic measurements underwhich the empire was divided, such as a tax register ofconquered lands (300 AD).

    In England, TheDomesday Bookby William the Conqueror(1086) covered all England and contained names of theland owners, area, land quality, and specific information ofthe areas content and habitants. It did not include mapsshowing exact locations.

    Continental Europe's cadastre was created in 1808. It wasfounded by Napoleon I A good cadastre will be mygreatest achievement in my civil law.

    Large-scale surveys are a necessary pre-requisite tomap-making. In the late 1780s, a team from the Ordnance

    Survey of Great Britain began the Principal Triangulation ofBritain using the specially built Ramsden theodolite.

    In the U.S., the creation of a national cadastre goes back tothe Land Ordinance of 1785 and the Northwest Ordinanceof 1787. These laws provided for the survey and settle-ment of the original thirteen colonies ceded to the federalgovernment after the War of Independence and of addi-

    Compiled by Ilse Genovese from Wikipedia; FIG Commission 2 Report on Education [schema by Prof. Stig Enemark (2001); a listingof surveying education programs in the U.S. by Rita Lumos, NSPS; careers-scotland.org.uk,http://outreach.eos.nasa.gov/ [source of

    geodesy image]; http://www.mnsengineers.com [surveying image].

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    tor or prism to return ambient light and thus measure distance,they are fully robotic, and they can send point data to the officecomputer and connect to satellite positioning systems, such asthe global positioning system (GPS). Robotics allows surveyorsto gather measurements at considerable speed and efficiency.The latest in surveying technology includes laser scanners.

    Types of surveys & applications

    ALTA/ACSM survey: A surveying standard jointly developedby the American Land Title Association and the AmericanCongress on Surveying and Mapping that incorporates ele-ments of the boundary, mortgage, and topographic surveys.ALTA/ACSM surveys, frequently shortened to ALTA surveys,are often required for real estate transactions.

    Archaeological survey: Used to determine the position ofarchaeological sites in a landscape or to record finds on anarchaeological site.

    As-Built survey: A survey conducted several times during a

    construction project to verify, for local government or regu-latory agencies, that the work authorized was completedto the specifications set on the Plot Plan or Site Plan. Thisusually entails a complete survey of the site to confirm thatthe structures, utilities, and roadways proposed were builtin the proper locations authorized in the Plot Plan or SitePlan.

    Bathymetric survey: A survey carried out to map the sea-bed profile.

    Boundary survey: Measures the actual physical extent of prop-erty ownership, typically witnessed by monuments or markersand recorded on a map or plat drawn from the data.

    Construction surveying ("lay-out" or "setting-out"): The pro-

    cess of establishing and marking the position and detailedlayout of new structures such as roads or buildings for sub-sequent construction.

    Deformation survey: A survey to determine if a structure orobject is changing shape or moving.

    Engineering surveys: Those surveys associated with engi-neering design, i.e. topographic, layout and as-built.

    Erosion and sediment control plan: A plan that is drawn inconjunction with a subdivision plan that denotes how up-coming construction activities will effect the movement ofstorm water and sediment across the construction site andonto abutting properties, and how this can be controlled.

    Foundation survey:A survey done to collect the positionaldata on a foundation that has been poured and is cured.Should not be confused with an As-Built survey which isnot to be done until all work on the site is completed.

    Hydrographic survey:A survey conducted with the purposeof mapping the coastline and seabed for navigation, engi-neering, or resource management purposes. Products ofsuch surveys include nautical charts.

    Mortgage survey or physical survey: A determination ofland boundaries and building locations; required by titlecompanies and lending institutions when they provide fi-nancing to show that there are no structures encroachingon the property and that the position of structures is gener-

    ally within zoning and building code requirements. Plot plan or site plan: A plan for a construction site that

    includes all existing and proposed conditions on a site, suchas structures, utilities, roadways, topography, and wetlands.The plan might also, but not always, include hydrology,drainage flows, endangered species habitat, FEMA FederalFlood Insurance Reference Maps and traffic patterns.

    Subdivision plan: A plot or map based on a survey of a parcelof land. Boundary lines are drawn inside the larger parcel toindicated the creation of new boundary lines and roads. Theplats are recorded in the cadastre (USA, elsewhere) or landregistry (UK). Always, upon finally completion of a subdivi-sion an As-built plan is required by the local government, tofacilitate the transfer of ownership of roadways from thedeveloper to the local government.

    Tape survey: This type of survey is the most basic and in-expensive type of land survey. Popular in the middle partof the 20th century, tape surveys, while being accurate fordistance, lack substantially in their accuracy of measuring

    angle and bearing. Topographic survey: A survey that measures the features

    and elevation of points on a particular piece of land andpresents them as contours and locations of improvements.

    Wetlands delineation & location survey: A survey that iscompleted when construction work is to be done on or near asite containing defined wetlands. Depending on the local, state,or federal regulations, wetlands are usually classified as areasthat are completely inundated with water more than two weeksduring the growing season. The boundary of the wetlands isdetermined by observing the soil PH, vegetation, erosion pat-terns or scour marks, hydrology, and morphology. A survey isdone to collect the data on the key locations and a plan is drawn

    to reference the boundary of the wetlands against the boundaryof the surrounding plots or parcels of land and the constructionwork proposed within.

    Surveying as a careerIn the U.S., surveying is recognized as a distinct profession

    apart from engineering. Depending on their specialization,surveyors may work as land surveyors, remote sensing andphotogrammetry surveyors, geodesists, hydrographers, miner-als and mining surveyors, and geomatics engineers. In addition,some countries recognize building and quantity surveyors.

    Building Surveyor

    Building surveying emerged in the 1970s as a profession inthe United Kingdom. In the U.S., these tasks are shared bysurveyors, appraisers, construction managers, and other pro-fessionals. The services they provide include, among others,construction design and building works, project managementand monitoring, insurance assessment and claims, and build-ing inspection to ensure compliance with building regulations.Clients of a building surveyor can be the public sector, localauthorities, and government departments, as well as privatesector organizations, and work closely with architects, planners,homeowners, and tenants groups. Building surveyors may also

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    be called to act as expert witnesses.They must undertake an accrediteddegree qualification and undertakeprofessional training for a period of atleast two years, at the end of whichthey sit an assessment of professionalcompetence.

    Geodetic SurveyorGeodetic surveying studies theshape of the Earth and determinesthe exact position of geographi-cal points. Geodetic surveyors useapplied mathematics to determine,by means of observations and mea-surements, the figures and areas oflarge portions of the Earths surface,or the general figure and dimensionsof the Earth; or that branch of sur-

    veying in which the curvature of theearth is taken into account, as in thesurveys of States, or of long linesof coast. [For further information,visit http://www.ngs.noaa.gov/ andhttp://www.aagsmo.org]

    GIS ProfessionalSurveyors now use laptop comput-ers, total stations, GPS, and geo-graphic information systems (GIS)technology to determine boundaries, elevation, and distance.GIS is a rapidly developing technique that focuses on spatial

    information (i.e., information that has a location). GIS profes-

    sionals apply spatial information in creating managementsystems for decision making at various levels of government.GIS professionals are involved in a wide variety of informationgathering activities and applications that enhance mankindsknowledge about the Earththe land, the oceans, naturalresources, and man-made features.

    HydrographerHydrographic surveyors carryout surveys of areas of watersuch as oceans, harbours andrivers. They use GPS, recording

    fathometers, echo sounders andtheodolites. They put survey datato a variety of uses, for exam-ple to draw up marine charts,locate inland water routesand to build sea defenses.Hydrographic surveyors carryout surveys of oceans, ports,harbours and inland waterwaysand rivers. They find out waterdepths and measure tides andcurrents. They also locate,identify and measure physicalfeatures such as rocks, sand-

    banks and sunken wrecks. Whentheyve collected the information,they analyze it using computers.Hydrographic surveyors makeoffshore surveys to find outwhere ships and boats can travel,to find suitable locations for oil orgas rigs, to develop sea miningprojects or to aid the recovery ofa sunken wreck. They conductinshore surveys on rivers and

    canals to predict the environmental effects of building marinas orflood defenses, assess the progress of dredging and maintain river

    channels for boats to use. Hydrographic cartographers use thesurvey data to produce and improve marine charts, navigation aidsand oceanographic publications. As a hydrographic surveyor youwill need to be strong in science and mathematics with a goodunderstanding of technology and computers. You should be ana-lytical, accurate and able to pay attention to detail. You will need awide knowledge of marine construction and law and should enjoyworking in or near a marine environment. [For other details, see p.52 for information on hydrographer certification, visit http://www.survmap.org/hydroapp.pdf.]

    Land SurveyorLand surveyors are licensed by state governments to estab-lish and mark land boundaries. This information is required

    to define ownership and rights in real property (land, water,mineral, easements, rights-of-way, etc.); to resolve bound-ary disputes between neighbors; and for any subdivision ofland, building development, and road boundary realignment.Licensing requirements vary by state, however these requirementsgenerally all have a component of education, experience and exam-inations. In the past, experience gained through an apprenticeship,together with passing a series of state-administered examinations,was required to attain licensure. Currently, many states require aBachelor of Science in Surveying, or a Bachelor of Science in CivilEngineering with additional coursework in surveyingin addition

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    spacecraft, satellite, buoy, or ship). In practice, remote sensing is thestand-off collection through the use of a variety of devices for gath-ering information on a given object or area. Thus, Earth observationor weather satellite collection platforms, ocean and atmosphericobserving weather buoy platforms, monitoring of a pregnancy viaultrasound, Magnetic Resonance Imaging (MRI), Positron EmissionTomography (PET), and space probes are all examples of remotesensing. In modern usage, the term generally refers to the use ofimaging sensor technologies including but not limited to the use

    of instruments aboard aircraft and spacecraft, and is distinct fromother imaging-related fields such as medical imaging.

    Quantity SurveyorQuantity surveyors play a key role in the organization andfinancial management of construction projects. Their job is tomanage costs effectively and to ensure that they get the bestvalue from contractors and suppliers. This involves obtainingtenders, arranging contracts, and managing costs for the clientwhile the works are undertaken. It is also their job to negoti-ate with the clients representative on payments and the finalsettlement. Quantity surveyors deal with other professionalswithin their company as well as clients out-with the organiza-

    tion. It is an extremely diverse area and can include projectmanagement, facility management, construction managementand management consultancy.

    to experience and examination requirements. [For alisting of accredited surveying programs, see pp.

    16.]

    Typically the process for registration followstwo phases. First, upon graduation, the candi-

    date may be eligible to sit for the Fundamentalsof Land Surveying exam, to be certified uponpassing and meeting all other requirements as aSurveyor In Training (SIT). Upon being certifiedas an SIT, the candidate then needs to gain addi-tional experience until he or she becomes eligiblefor the second phase, which typically consists of the Principlesand Practice of Land Surveying exam along with a state-spe-cific examination. Registered surveyors usually denote them-selves with the letters P.S. (professional surveyor), L.S. (landsurveyor), P.L.S. (professional land surveyor), or P.S.M. (profes-sional surveyor and mapper) following their names, dependingon the dictates of their particular state of registration. Typically,a licensed land surveyor is required to seal all plans; the format

    of the seal is dictated by their state jurisdiction, which showstheir name and registration number. In many states, land sur-veyors are also required to place caps bearing their registrationnumber on property corners that they have set. [For profes-sional certifications, scholarship awards, and other programs,visit http://www.nspsmo.org.]

    Mineral/Mining SurveyorMinerals/mining surveyors map mineral deposits. Their tasksinclude working out the potential use and value of mineraldeposits, managing and developing mines, and forecastingpossible environmental effects of mining, such as air pollution.As a minerals/mining surveyor you need to be good at math-

    ematics. You also need to be familiar with electronic instru-ments, computers and computer-aided design techniques.Minerals/mining surveyors need a wide knowledge of miningeconomics, planning legislation, health and safety issues andmineral properties. In dealing with planning matters with localauthorities you will need to have good communication skills.

    Photogrammetric mappingPhotogrammetry is a remote sensing technology in whichgeometric properties about objects are determined from pho-tographic images. Photogrammetry is used in different fields,such as topographic mapping, architecture, engineering, man-ufacturing, quality control, police investigation, and geology,as well as by archaeologists to quickly produce plans of largeor complex sites. It is also used to combine live action withcomputer generated imagery in movie post-production; FightClub is an excellent example of the use of photogrammetry infilm.

    Remote sensingIn the broadest sense, remote sensing is the short or large-scaleacquisition of information of an object or phenomenon, by the useof either recording or real-time sensing devices that is not in physi-cal or intimate contact with the object (such as by way of aircraft,

    surveying

    Surveyors Review Course

    Co-sponsored by the University of Missouri-Rollaand Missouri Society of Professional Surveyors,the 2007 surveyor refresher course will cover

    Exam Preparation, Legal Principles, USPLSS, ErrorsAnalysis, Route Surveys, Celestial Observations,Instrumentation, Photogrammetry, GPS Surveys,State Plane Coordinates, Problems Session, andPractice NCEES-like Exams. Instructors Dick Elgin,Joe Paiva, Norman Brown. $795.00. Contact:Engineering Continuing Education, UMR, Rolla,Missosuri 65409; 573-341-4132.

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    Accredited surveying programs at U.S. colleges. [Extracted from a 2006 compilation by Rita Lumos.]

    surveying: educationalinstitutions

    State Institution Location Program Degree Accreditation

    Alaska University of Alaska Anchorage Anchorage Geomatics BS ABET/ASAC

    CaliforniaCalifornia State Polytechnic

    UniversityPomona

    Geospatial Engr. Option in Civil

    Engr.BS ABET/EAC

    California California State University, Fresno Fresno Geomatics Engineering BS ABET/EAC

    Colorado Metropolitan State College of Denver Denver Surveying and Mapping BS ABET/ASAC

    Florida University of Florida Gainesville GeomaticsBS, MS,

    PhDABET/ASAC

    GeorgiaSouthern Polytechnic State University Marietta Surveying and Mapping BS ABET/ASAC

    Indiana Purdue UniversityWest

    LafayetteLand Surveying Engineering

    BS, MS,

    PhDABET/EAC

    Kentucky Murray State University, College of

    Industry & Engineering TechnologyMurray Civil Engineering Technology BS, ETA CE ABET/TAC

    Louisiana Nicholls State University Thibodaux Geomatics BS ABET/ASAC in

    progress

    Michigan Michigan Technological University Houghton Surveying Engineering BS ABET/ASAC

    Michigan Ferris State University Big Rapids Surveying Engineering BS ABET/EAC

    New Jersey New Jersey Institute of Technology Newark Surveying Engineering

    Technology

    BSET ABET/TAC

    New Jersey Essex County College Newark, NJCivil Construction Engineering

    Technology, Land Surveying

    Option (Dual Admin. w/ NJIT)

    AAS CE ABET/TAC

    New Mexico New Mexico State University Las Cruces Surveying Engineering BS ABET/EAC

    New York Alfred State College Alfred Surveying Engr. Technology BS, AAS ABET/TAC

    New York Mohawk Valley Community College Utica Surveying Technology AS ABET/TAC

    New York Paul Smiths College Paul Smiths Surveying Technology AS ABET/TAC

    Ohio The Ohio State University Columbus Geomatics Engineering BS ABET/EAC

    OhioThe University of Akron Community

    and Technical CollegeAkron

    Surveying Engineering

    Technology

    BS, AAS ABET/TAC

    Ohio Cincinnati State Technical

    Community CollegeCincinnati

    Civil Engr. Tech. - Surveying

    MajorAS CE ABET/TAC

    Ohio Sinclair Community College DaytonCivil Engineering Technology,

    Surveying CertificateAAS CE ABET/TAC

    Ohio Stark State College of Technology North CantonCivil Engr. Tech.-Surveying

    OptionAAS CE ABET/TAC

    Oregon Oregon Institute of Technology Klamath Falls Geomatics BS ABET/ASAC

    Pennsylvania Pennsylvania College of Technology Williamsport Surveying Technology AS ABET/TAC

    PennsylvaniaPennsylvania State University,

    Wilkes-Barre Campus,

    Commonwealth College

    Wilkes-Barre Surveying Technology AS ABET/TAC

    South Carolina

    Greenville Technical College Greenville Geomatics Technology AS ABET/TAC

    Tennessee East Tennessee State University Johnson City Surveying and Mapping BS ABET/ASAC

    Tennessee Chattanooga State University Chattanooga

    Civil Engineering

    Technology,Surveying

    Certificate

    AAS CE ABET/TAC

    Texas Texas A&M University at Corpus

    ChristiCorpus Christi

    Geographic Information

    ScienceBS ABET/ASAC

    Virginia Old Dominion University NorfolkCivil Engineering Technology,

    Surveying & Site DevelopmentAAS CE ABET/TAC