Survey + Geospatial Knowledge Center
Understanding the ever-changing world of land surveying
CEC’s clients have relied on our multi-disciplinary team’s expertise for more than 30 years. Like all technical fields, land surveying and geospatial engineering has its own individual and rapidly changing terminology. This glossary is here to help enhance communications with our clients.
determines property lines and defines true property corners of a parcel of land described in a deed. The survey also indicates the evidence of encroachments and disclosed easements, and may show the limitations imposed on the property by state or local regulations.
a comprehensive boundary survey that adheres to the national standards adopted by the American Land Title Association and the National Society of Professional Surveyors. The survey is designed to satisfy the needs of lenders, corporations, and title companies for the purpose of extended title coverage for commercial properties.
locates surface features of a property and depicts natural features, terrain contours, and elevations on a plat or a 3D CAD file.
locates the position of underground utilities delineated by the location of surface evidence and markings and/or maps provided by a sub-surface utility engineering company or a public utility One Call service.
the horizontal and/or vertical location of existing conditions of site improvements that are normally performed upon completion of construction work. The survey is used by others to determine substantial conformance to design.
a process involving setting survey control points in and around project sites so those points can be used for aerial control, machine control, and construction and linear projects.
setting survey points with grades for planned site improvements such as buildings, parking lots, utilities, and other associated site elements.
conducted to determine the volume of a stockpile by comparing the surfaces of two or more topographical surveys completed at different points in time in the same location. This service can be provided using conventional survey methods, terrestrial LiDAR, or UAS.
periodic surveys using stable survey control monuments to monitor long-term movements and settlements of structures and slopes over a given period of time.
linear projects that involve locating utilities, roads, streams, structures, and boundary lines, and that usually include topographic features to prepare construction plans, easements, and right-of-way maps.
boundary, topographic, and utility surveys along a specific pipeline corridor for use in permitting and design.
identifies the horizontal and vertical location of pipeline features such as pipe joints, valves, and risers.
typically used for GPS surveys where the accuracy requirements are not as stringent. Often used for mapping inventories of signage, utilities, trees, or delineated wetlands. These surveys are typically accurate to within one meter.
identifies the location of individual trees with a minimum diameter as specified in a contract. The location information includes species and tree diameter. Often a numbered tag is attached to the tree and recorded for subsequent arborist inventory and assessment.
used in projects such as a stream restoration or no-rise certifications. These are typically detailed topographic surveys including hydrographic and geomorphic features of the banks, thalweg, and floodway
used to determine whether a structure is located within a special flood hazard area for flood insurance purposes.
a boundary survey where a parcel of land is subdivided into smaller lots and may require approval from a local planning department.
preparation of legal descriptions and exhibits for use in establishing a right to cross or otherwise using someone’s land for a specified purpose.
preparation of legal descriptions, plats of survey, or exhibits for the purpose of the legal transfer of real property from one owner to another.
an underwater topographic survey used to measure the depth and location of underwater features using sonar technology and GPS mounted to a boat or unmanned vessel. These surveys are useful for pre- and post-dredging activities.
a bathymetric survey used to measure the depth and location of underwater features before and after the removal of silt, sediment, or other material from the bottom of a water body by dredging.
a bathymetric survey used to locate debris following bridge demolition for the purpose of confirming that all debris has been recovered and will not impede any nautical traffic through the waterway.
a bathymetric survey used for the purpose of determining the draft depth (the minimum depth of water in which a ship or boat can safely navigate) and the extents and depths of a trench.
a bathymetric survey used for the purpose of calculating the storage volume or the average time a molecule of water is resident in a reservoir or leachate water impoundment pond.
a bathymetric survey used to measure the depth and location of underwater features for utility crossings or horizontal directional drilling that crosses a river, stream, pond, or lake.
thermal imaging technology used to detect very small fugitive emissions of greenhouse gases and other smog-forming volatile organic compounds (VOCs). Mounting an OGI camera to a UAV allows for quick and safe detection and visualization of fugitive emissions leaks so facility owners and operators may repair leaks, prevent major damage, and comply with local and federal regulations. CEC employs certified OGI Thermography Technicians to comply with EPA OOOOa reporting.
used to conduct topographic surveys, optical gas imaging, vegetation analysis, and various types of inspections, as well as to capture aerial photography.
using near-infrared (NIR) and multispectral cameras to generate Normalized Difference Vegetation Index (NDVI) images for use in establishing vegetative cover percentages necessary for close-out of NPDES and ESCGP-2 permits and the release of bonds in mining, among other uses. In agricultural applications, NDVI mapping can help maximize crop yields and provide data to assess environmental conditions for agriculture and environmental projects/ permits. Images are used to monitor soil composition and vegetative health, as well as measure and monitor plant growth, vegetation cover and soil/water condition, and biomass production.
thermal signatures from wastewater discharges, cooling towers, groundwater seeps and springs, etc., as well as building and equipment heat loss that are captured through the use of infrared cameras. UAS can be outfitted with infrared cameras to obtain thermal imagery.
using UAS inspection media in conjunction with a physical site inspection by a Registered Professional Engineer or Architect to develop a façade inspection report for permits, licenses, and other similar required needs.
using UAS to visually monitor rights-of-way for both overhead and underground utilities to determine if revegetation efforts have been successful, if there is evidence of earth movements such as slumps and slides, if there has been unauthorized construction or storm damage, or if there is vegetative intrusion into overhead utility lines. UAS can be flown manually by an operator in visual contact with the UAS or pre-programmed to fly a specific flight path.
scanning features within an environment using Light Detection and Ranging (LiDAR) equipment to produce a three-dimensional (3D) model. LiDAR utilizes a laser light and reflected light to measure distances. The equipment can be used on drones, vehicles, and standalone terrestrial equipment such as a tripod. Typically used for topographic surveys.
accurate measurement surveys using conventional survey methods or terrestrial LiDAR to locate bridge features, including abutments, beams, bearings, decks, piers, etc., for the purpose of renovating, expanding, or rebuilding bridges.
completed on mining sites for boundary and topographic location, quantities, alignments, and mapping purposes. These surveys can occur both above and below ground with specialized mining safety training.
incorporating LiDAR 3D scanning and models that identify and tag features incorporated in a Geographic Information System (GIS) to allow facility owners to track inventories, operations, and maintenance of requested features.
using 3D laser scanning technology with terrestrial LiDAR capabilities to provide data used in exploring facility upgrade cost reduction. Rapid data collection and survey-grade spatial data imaging expedites capital project, maintenance, and plant retrofit efforts, resulting in enhanced project schedules, reduced downtime, and improved change order management.
surveys to locate the features of a landslide area, including the crown, scarps, cracks, ridges, tip, and toe, and periodic surveys using stable survey control monuments to monitor long-term movements and settlements of a landslide or remediation features over a given period of time.
A branch of engineering practice that involves managing certain risks associated with utility mapping at appropriate quality levels, utility coordination, utility relocation design and coordination, utility condition assessment, utility data communication to concerned parties, utility relocation cost estimates, utility accommodation implementation policies, and utility design.
The process of using a surface geophysical method or methods to interpret the presence of a subsurface utility and to mark its approximate horizontal position (its designation) on the ground surface. (Note: Utility owners and contractors sometimes call this process “locating.”)
Any of a number of methods designed to utilize and interpret ambient or applied energy fields for the purpose of identifying properties of, and structure within, the earth. Such methods typically include variants of electromagnetic, magnetic, elastic wave, gravitational, and chemical energies.
Precise horizontal and vertical location of utilities obtained by the actual exposure (or verification of previously exposed and surveyed utilities) and subsequent measurement of subsurface utilities, usually at a specific point. Minimally intrusive excavation equipment is typically used to minimize the potential for utility damage. A precise horizontal and vertical location, as well as other utility attributes, is shown on plan documents. Accuracy is typically set to 15-mm vertical and to applicable horizontal survey and mapping accuracy as defined or expected by the project owner.
Information obtained through the application of appropriate surface geophysical methods to determine the existence and approximate horizontal position of subsurface utilities. Quality level B data should be reproducible by surface geophysics at any point of their depiction. This information is surveyed to applicable tolerances defined by the project, and added to plan documents.
Information obtained by surveying and plotting visible above-ground utility features and by using professional judgment in correlating this information to quality level D information.
Information derived from existing records or oral recollections.
The process of exposing and recording the precise vertical and horizontal location of a utility.
A geophysical method that uses radar pulses to create an image of the subsurface using electromagnetic radiation in the microwave band (UHF/VHF frequencies) of the radio spectrum, detecting the reflected signals from subsurface structures.
Visual inspection of the interiors of pipelines, plumbing systems, and storm drains.