ID Land Surveyor common mistakes
ID Land Surveyor · Understand the traps and how to avoid them.
Treating boundary retracement as a math problem: accepting a found monument's position only when it agrees with the record bearings and distances, and 'correcting' or ignoring monuments that disagree by more than a foot or so.
Candidates study boundary principles as definitions to memorize but practice on computational problems, so under exam pressure the habit of recomputing from record data takes over. The principle that monuments control over courses and distances is easy to recite and hard to apply when the numbers conflict.
What to do instead
For every retracement item, write the hierarchy explicitly before computing: original monuments and their evidence, then natural monuments, then artificial monuments in the original survey, then courses and distances, then area, then adjoiner lines. When a question gives a monument that conflicts with record, answer from the hierarchy and treat the record dimension as evidence of where the monument should be, not as the controlling position. Practice with items where the monument is off by a large, clearly deliberate amount so the habit is reinforced.
Applying proportional measurement (a 'compass rule' or 'proportionate' adjustment) to restore lost corners in a section framework without first identifying the correct controlling corners, or applying it to subdivision or lot lines where it does not belong.
Proportional measurement looks like a single formula, so candidates memorize one procedure and apply it everywhere. The actual rule depends on which corners exist, which are lost, and whether the line is a section line or a subordinate division, and those distinctions are learned by case, not by formula.
What to do instead
Before any proportion, classify each corner in the problem as existent, obliterated, or lost, and identify the parent corners that control the line. For PLSS work, use the single-proportion method between the nearest existent controlling corners and the double-proportion method only for interior lost corners controlled by four existent corners. Do not use proportion for record lot lines in a platted subdivision; those are retraced by their own monumentation. Work a set of short problems that differ only in which corners are missing so the case selection becomes automatic.
Mishandling the difference between geodetic and grid bearings: mixing a geodetic azimuth with a grid azimuth, or applying a scale factor and convergence in the wrong order or to the wrong quantity.
State plane computations are taught as a chain of corrections, and candidates memorize fragments (grid factor, elevation factor, convergence) without a firm grasp of what each one does to a distance or a direction. Under time pressure the corrections get applied in the wrong sequence or to the wrong quantity.
What to do instead
Separate the two problems in your notes. For distances: ground distance to ellipsoid uses the elevation factor (R/(R+h)), ellipsoid to grid uses the grid scale factor, and the combined factor is their product. For directions: convergence converts between geodetic and grid azimuth, and the sign depends on your position relative to the central meridian. Do a few full worked examples from ground coordinates to grid coordinates and back, checking units and signs at each step, and memorize the sign convention rather than the formula alone.
Confusing accuracy and precision, and confusing error sources: reporting a blunder as random error, or claiming a closed traverse's small misclosure proves high accuracy.
The terms are defined simply in texts but the exam tests them through scenarios, and a small random misclosure is intuitive evidence of good work. Candidates also tend to classify any large error as 'systematic' because that sounds more technical than 'blunder'.
What to do instead
Anchor each term to a testable definition: precision is repeatability, accuracy is closeness to truth, a blunder is a gross mistake detectable by redundancy, systematic error is consistent and correctable, random error is unavoidable and estimated statistically. For any scenario item, ask whether redundancy exists (if not, no misclosure can be computed) and whether the error has a consistent direction. Practice classifying short scenarios until the mapping is immediate.
Computing a misclosure and then distributing it without weighting, or reporting the misclosure in the wrong units or as a ratio built incorrectly (for example, misclosure divided by perimeter inverted).
The compass rule is the only adjustment many candidates have practiced, so every closure problem gets the same equal-perimeter treatment. The relative precision ratio is also easy to invert under pressure, and an inverted ratio still looks plausible.
What to do instead
Decide the weighting before dividing: equal per leg for compass rule, proportional to length for transit rule, and note when the exam expects a specific method. Write the ratio as (perimeter / misclosure) and sanity-check it: a ratio of 1:5,000 means about 1 part in 5,000, so a 0.1 ft misclosure on a 500 ft traverse is 1:5,000, not 1:50. Always attach units and state the ratio as a comparison, then verify the adjusted traverse closes exactly.
Applying a vertical or horizontal curve formula outside its valid range, or using the wrong formula for the element asked: for example, using the arc definition of degree of curve where the chord definition applies, or using R = 5729.58/degree for a chord-defined curve.
Curve formulas look interchangeable, and candidates memorize one constant (5,729.58) without remembering it comes from the arc definition with a 100 ft arc. Railroad and some highway problems use the chord definition, where the constant differs, and the exam can test either.
What to do instead
Build a one-page curve sheet with the arc-definition constant (5,729.58) and the chord-definition constant (approximately 5,729.65, derived from R = 50/sin(D/2)) side by side, and label which is which. For each problem, identify the definition stated, then select the formula. Practice computing all elements (T, L, LC, E, M, external, middle ordinate) from a single given set so you see which formulas depend on the definition and which do not.
Ignoring the distinction between horizontal and vertical datum in elevation problems: mixing ellipsoid heights with orthometric elevations, or forgetting that a level loop closure and a GNSS-derived height are not directly comparable without a geoid model.
GNSS and differential leveling are taught in separate chapters, so candidates do not build the bridge between them. On the exam, a question that mixes a GPS-derived height with a benchmark elevation looks like a simple subtraction.
What to do instead
Write the relation once and keep it visible: h (ellipsoid) = H (orthometric) + N (geoid undulation). Any problem that compares GNSS heights to benchmark elevations must pass through N. Also track which datum each given value is on before subtracting. Do a few conversion problems in both directions, and check whether the geoid undulation is given or must be inferred.
Reading a metes-and-describes or deed description literally without resolving ambiguities: treating a call for an adjoiner as a bearing and distance, ignoring the order of calls, or failing to recognize a call to a monument as controlling over a call to an adjoiner's line.
Deed reading is a language skill tested through long, deliberately ambiguous descriptions, and candidates under time pressure skim for numbers and start computing. The controlling-call rules are stated in prose and are easy to skip.
What to do instead
Read the entire description once without writing, then list the calls in order and mark each as monument, course and distance, adjoiner, or area. Apply the same hierarchy used for retracement, and note that a call to an adjoiner's line is generally subordinate to a call to a monument at a definite location. Practice by writing a short plain-language summary of each description before answering, which forces the ambiguity to surface.
Skipping units and significant figures: reporting an area in the wrong unit, mixing degrees-minutes-seconds with decimal degrees, or carrying more precision than the input data supports.
Calculators and software return many digits, and candidates copy them into answers without considering what the field data supports. Angle formats are also easy to mix because both appear in the same problem sets.
What to do instead
Adopt a fixed workflow: convert all angles to decimal degrees for computation, convert back to DMS for the answer, and state the unit on every number. Decide the appropriate precision from the least precise given value, and round only at the end. For areas, confirm whether the answer is expected in square feet, acres, or square meters and convert explicitly (43,560 sq ft per acre).
Answering ethics and standards-of-practice items from general intuition rather than from the specific statutory framework: for example, assuming a surveyor may seal work performed entirely by an unlicensed technician, or that a survey can be recorded without the required monumentation.
Ethics questions read like common-sense scenarios, so candidates answer quickly. But the exam tests jurisdiction-specific rules on responsible charge, sealing, monumentation, and records, which often differ from what feels reasonable.
What to do instead
Build a short reference list of the rules the exam actually tests: who may seal what, what constitutes responsible charge, when monumentation is required before recording, and the record-of-survey requirements. For each scenario, identify which rule is being tested before choosing. Where the exam is jurisdiction-specific, study that jurisdiction's statute and board rules directly rather than relying on general professional-ethics material.