IL Land Surveyor key terms

A physical object such as a stone, iron pin, or pipe that is cited in a recorded deed or plat as marking a corner, and whose position controls over recited distances and bearings when the two conflict.

A corner established by the original federal survey of the public lands, evidenced by the original bearing trees, mounds, or marked stone, and generally held unalterable regardless of later measurement error.

The statutory and professional obligation to reestablish a lost or obliterated corner at its original position using accepted evidence and procedures, and to file a record of that reestablishment with the proper authority.

A method of restoring a lost corner by dividing the record distances between existing controlling corners in proportion to the discrepancy found, used only when no acceptable physical evidence of the original position survives.

A corner whose original position cannot be recovered from any physical evidence or reliable testimony, so that its location must be reestablished by proportionate measurement between the nearest existing controlling corners.

A corner whose monument is gone or disturbed but whose original position can still be recovered through evidence such as bearing trees, accessory marks, or credible testimony, so it is treated as existing rather than lost.

Physical traces, testimony, or records that support the location of a corner without themselves being the monument, such as bearing trees, fence lines, and old field notes.

A tree marked and recorded by the original surveyor near a corner, whose scar, blaze, or stump can be used to reconstruct the corner position when the monument itself is missing.

The subdivision of a section into aliquot parts and fractions under the rectangular system, where the center of the section is fixed first and the resulting lots absorb the excess or deficiency.

A fractional parcel created by the original federal survey, typically along a meander line, water boundary, or correction line, and designated by lot number on the official plat rather than by aliquot description.

A line run by the original surveyor to approximate the bank of a body of water for computing area; it is not a boundary of title, which generally follows the water itself.

A property line that follows the edge of a navigable or non-navigable water body, with the location of the boundary determined by rules of accretion, reliction, erosion, and avulsion rather than by survey measurement alone.

The gradual and imperceptible addition of land along a water boundary through natural deposition, which ordinarily belongs to the adjacent riparian owner without a new deed or survey.

A sudden and perceptible change in a watercourse, such as a flood cutting a new channel, which does not shift property boundaries; the old line generally remains the boundary.

A doctrine by which a person who occupies land openly, notoriously, exclusively, continuously, and hostilely for the statutory period may acquire title, subject to Illinois statutory requirements and exceptions.

A right to use another's land acquired through open, adverse, and continuous use for the statutory period; unlike adverse possession it grants use rights rather than title to the land.

A settlement in which adjoining owners whose true line is uncertain agree on a boundary and treat it as binding, resolving the dispute without litigating the original deed location.

An implied easement arising when a parcel is landlocked or lacks practical access, allowing the owner to cross a neighboring parcel to reach a public way.

Uncertainty in a conveyance arising from conflicting calls, such as a distance that contradicts a monument or a description that fits more than one parcel, resolved by established rules of construction.

The hierarchy courts apply to conflicting deed calls, generally preferring natural monuments, then artificial monuments, then courses and distances, then area, and considering the intent of the parties.

The chronological sequence of recorded conveyances, mortgages, and liens affecting a parcel, used to establish ownership and to identify what interests a survey must account for.

An examination of public records to trace ownership and encumbrances on a parcel, typically performed before a boundary survey so the surveyor knows which documents define the lines.

A drawing and written record of a boundary survey filed with the county recorder or other designated office, showing monuments found or set, boundaries determined, and relevant discrepancies.

A recorded document used to correct a previously recorded plat or map that contains an error, adding or correcting information without altering the original document itself.

The Illinois statute governing subdivision and resubdivision of land, requiring plat approval and recording before lots are conveyed, and setting standards for monuments and dedications.

The statutory scheme under which Illinois registers land surveyors through the Department of Financial and Professional Regulation, requiring education, experience, and examination before a license is issued.

The ethical duty to accept only work the surveyor is qualified to perform, to keep current with technology and law, and to supervise subordinates whose work is offered as the licensee's own.

The licensed surveyor's authentication of professional work, applied only to documents the licensee prepared or directly supervised, and required on plats and reports submitted to public agencies.

A situation in which the surveyor's personal, financial, or family interest could bias professional judgment, requiring disclosure and often withdrawal from the engagement.

The degree of care, skill, and knowledge ordinarily exercised by competent surveyors practicing under similar circumstances, used to judge negligence in professional work.

A system of projected coordinates defined for each state, using a specified map projection and datum, so that survey points can be expressed on a common grid for mapping and record keeping.

The reference framework of coordinates and ellipsoid parameters to which horizontal positions are tied, such as NAD83, defining the origin and orientation for survey and mapping coordinates.

A mathematical model of the earth's surface formed by rotating an ellipse, used as the reference surface for geodetic coordinates and map projections.

The equipotential surface of the earth's gravity field that approximates mean sea level, used as the reference for orthometric heights and for relating GPS-derived ellipsoid heights to elevations.

A height above the geoid, commonly called elevation, obtained by correcting a GPS ellipsoid height using a geoid model for the local area.

A mathematical transformation that converts positions on the curved earth to a flat map surface, inevitably introducing scale distortion that must be accounted for in precise surveys.

The ratio between a distance on the projection grid and the corresponding distance on the reference ellipsoid, applied when converting between ground measurements and grid coordinates.

A survey method in which a series of connected courses is measured for direction and distance to determine coordinates of points, with closure computed to assess the accuracy of the work.

The amount by which a survey traverse fails to return to its starting point or known control, expressed as linear and angular misclosure and compared against an allowable tolerance.

A statistical method that distributes random measurement errors across a network so the sum of squared residuals is minimized, producing the most probable coordinates and an estimate of precision.

An electronic instrument combining an electronic theodolite with an electronic distance meter, used to measure horizontal and vertical angles and distances to targets for coordinate computation.

A correction applied to electronic distance measurements to account for the offset between the instrument's reference point and the prism's reflective surface, which varies by prism type.

An adjustment applied to electronic distance measurements to compensate for the effect of air temperature, pressure, and humidity on the speed of the measuring signal.

Real-time kinematic positioning, in which a rover receives corrections from a base station or network to compute centimeter-level coordinates in the field as observations are collected.

The regulatory requirements adopted by the State of Illinois specifying what a boundary survey must include, such as monumentation, research, fieldwork, and the content of plats and reports.