A land surveyor ultimately measures the earth using three parameters: distance, direction, and elevation. The industry has come a long way since twelve-man crews pulling chains across the prairies. Technology allows a two-man field crew exponential productivity and accuracy.
An electronic distance measurer (EDM) and data collector are now considered conventional equipment. They are used when a line of sight is available and sub-hundredth accuracy is required. The growing trend today is Robotic EDM, allowing a one-person crew to survey accurately without the need of an Instrument man.
Another breakthrough in the past 15 years is the use of global navigation satellite system (GNSS). This system works best when there is a clear view of the sky and sub-tenth accuracy is required. The most accurate GNSS setup is stationary, called static. The most convenient data collection setup is known as real time kinetic (RTK). Although mobile, it is not very accurate. When the two setups are combined, known as a base with a rover, GNSS becomes accurate and mobile.
By far, the most accurate piece of equipment a surveyor uses is a level. Although it is rarely used in horizontal measurement, it must be used to guarantee elevations. The curvature of the earth distorts vertical measurements in as little as 300 feet! Good practice, redundant readings, and data reduction will produce accurate elevations even miles from a known benchmark.
The data collected in the field must be processed into maps or design plans. With the help of computer aided design (CAD), large amounts of data can be graphically represented to show contours and features and improvements and developments. Extra information, like text or an aerial photograph, can also be added.
The ability to integrate multiple formats of data into a user friendly platform is known as geographical information systems (GIS). Most municipals have their utility systems in this format. Most pipeline companies use aerial images with unit lines overlaid. Most appraisal districts integrate numerical data with parcel maps.
What might take 5 hours in the field to survey, might take 20 hours in the office to produce a legible map or plat.
Texas has a Metes and Bounds survey system, which means we measure boundaries. Measurement is always riddled with error and boundaries are left to interpretation. Engineering is a science, Law is left to the legal system, and Surveyors find themselves somewhere in between. That is why two surveyors often come to differing opinions, and both could be correct.
Legal research is the primary responsibility of a land surveyor. Deeds, unwritten conveyances, easements, testimony, adjacent property owners, and date of the original survey all play important roles in boundary location.
The only recourse to a surveyor’s opinion is through the state’s regulatory Board of Professional Land Surveying and a court of law. Often called as an expert witness, land surveyors do not make warranties or offer opinions as to matters of unwritten title, adverse possession, acquiescence, or estoppels.
The unique combination of outdoorsman, technician, and statesman are what makes land surveying a wonderful career. George Washington made his career as a surveyor before becoming an officer, along with two other presidents carved on Mt. Rushmore.
Most survey personnel have a rewarding career as technicians. Others, the combination of education and experience allow them to take the Fundamentals of Surveying test to become Surveyors in Training. After a lengthy apprenticeship, the state Board will vote on applicants to take a legal exam and an analytical exam. Upon completion, the once rodman with a machete is assigned a seal and can legally determine boundaries as a Registered Professional Land Surveyor.
If this interests you, please contact Southern Survey and Design or your local community college for more information.