NE Land Surveyor common mistakes
NE Land Surveyor · Understand the traps and how to avoid them.
Treating a metes-and-bounds description as controlling without checking for a senior right or a call for an adjoiner that contradicts the courses and distances.
Candidates memorize 'monuments control over distances' but apply it mechanically, ignoring the hierarchy of calls (natural monuments > artificial monuments > courses and distances > area) and the effect of seniority when two surveys conflict.
What to do instead
Before answering, list every call in the description and rank it by the hierarchy. Then check whether the parcel is junior or senior to the adjoiner and whether a call for a monument (e.g., 'to the iron pin set at the corner of Smith') is a call for a specific physical object or a general reference. Practice with descriptions that contain a deliberate conflict between a bearing and a called monument.
Computing a boundary closure using grid bearings and distances without reducing field measurements to the appropriate projection surface, then reporting a misclosure that is actually a scale or convergence artifact.
Candidates mix ground distances, ellipsoid distances, and grid distances in the same traverse, especially when using state plane coordinates or a low-distortion projection. They also forget to apply the convergence angle when orienting grid bearings.
What to do instead
Adopt a consistent workflow: reduce all measured distances to the ellipsoid (or to the grid) using the combined factor, and rotate ground bearings to grid bearings by the convergence angle before computing closure. In the exam, write the reduction step explicitly and check the magnitude of the expected scale effect (e.g., 1 part in 10,000 at 1,000 m elevation) before declaring a blunder.
Setting construction stakes directly from a CAD drawing or a total station resection without verifying the control network and the design coordinates against an independent source.
Candidates assume the drawing coordinates are correct and that the control points are where the drawing says they are. They skip the check that the total station is oriented to the correct baseline and that the design file uses the same units and coordinate system as the control.
What to do instead
Establish a written checklist: (1) confirm the coordinate system and units of the design file; (2) verify at least two control points by an independent measurement (e.g., a second setup or GNSS check); (3) compute a closed traverse or a resection with a known check point; (4) compare the computed position of a design point with a scaled position from the plan. In the exam, look for questions that describe a stakeout error caused by a wrong backsight or a unit mismatch.
Using a GIS layer or a remotely sensed image as if it were a survey-grade measurement without accounting for positional accuracy, datum, and scale.
Candidates treat GIS data as precise because it is digital. They ignore the stated accuracy (e.g., 'meets NMAS at 1:12,000'), the datum shift between NAD27 and NAD83, and the effect of raster resolution on boundary location.
What to do instead
For any GIS or remote sensing question, identify the source accuracy, the datum, and the intended use. Convert coordinates explicitly if datums differ, and compare the stated accuracy to the tolerance required by the task. If the task is boundary determination, state that GIS data is not a substitute for a field survey and explain what field evidence would be needed.
Deriving a hydrographic position or depth without correcting for tide, draft, sound velocity, or the offset between the GNSS antenna and the transducer.
Candidates focus on the horizontal position and forget the vertical reductions that make a bathymetric surface meaningful. They also mix ellipsoid heights, chart datum, and tidal datums.
What to do instead
Build a vertical budget: measured depth + transducer draft − tide (or water level) = reduced depth relative to chart datum. Apply sound-velocity correction from a probe or a salinity-temperature-depth cast, and reduce the GNSS height to the same datum. In the exam, check whether the question gives a tide reading and a draft; if so, apply both explicitly.
Classifying LiDAR or UAS point clouds into ground and non-ground without validating the classification against independent ground checkpoints, then using the resulting DEM for design or volumetrics.
Candidates trust the software's default classification and do not check for vegetation, buildings, or steep terrain where the classifier fails. They also ignore the difference between relative and absolute accuracy.
What to do instead
Require a independent check: compare the classified ground surface to surveyed checkpoints in open, vegetated, and steep areas, and report the vertical RMSE. For volumetrics, state the method (e.g., breakline-enforced TIN vs. raw point cloud) and the expected error. In the exam, look for questions that give a checkpoint residual and ask whether the surface meets a specification.
Applying a zoning or subdivision regulation without checking the effective date, the vested rights, and the difference between a conforming and a legally nonconforming lot.
Candidates read the current code and apply it retroactively, or they confuse a variance with a special exception. They also overlook that a plat may have been approved under an earlier ordinance.
What to do instead
For any land development question, establish the timeline: when was the parcel created, what were the regulations at that time, and has the use continued? Distinguish nonconforming use from nonconforming lot, and variance from special exception. In the exam, if a date is given, check whether the regulation in question was in effect on that date.
Ignoring the legal distinction between a boundary survey and a location survey, or between an easement and a fee taking, when interpreting a right-of-way or a plat.
Candidates treat all lines on a plan as property lines. They do not ask what interest is being conveyed or what the survey was intended to show.
What to do instead
Before answering a legal principles question, identify the type of survey (boundary, location, topographic, ALTA/NSPS), the type of interest (fee, easement, lease), and the standard of care. Read the legend and the notes on the plat. If the question describes a dispute, ask whether the surveyor was retained to determine the boundary or merely to locate improvements.
Computing a geodetic azimuth or a state plane coordinate without accounting for the difference between geodetic and grid north, or between orthometric and ellipsoid heights.
Candidates use a single formula (e.g., inverse between grid coordinates) and forget that the grid azimuth differs from the geodetic azimuth by the convergence angle, and that a GNSS-derived ellipsoid height must be converted to an orthometric height using a geoid model.
What to do instead
For any geodesy question, write the reduction chain: geodetic azimuth → grid azimuth (apply convergence), ellipsoid height → orthometric height (apply geoid separation), ground distance → grid distance (apply combined factor). Check the sign conventions and the magnitude of each correction before selecting an answer.
Failing to document the basis of a boundary determination or a construction layout, so that the reasoning cannot be reproduced or defended.
Candidates focus on the final number and not on the record. They do not write down the evidence considered, the hierarchy of calls applied, or the checks performed.
What to do instead
Use a standard documentation template: list the sources (deeds, plats, field evidence), state the hierarchy applied, show the computations, and record the checks (closure, independent measurement, comparison to record). In the exam, questions about professional practice often hinge on whether the surveyor can demonstrate the basis of the opinion; choose the answer that includes a written record and a clear statement of the evidence.