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CONVERSION IS OUT, MEASURE IS IN -- ARE WE BEGINNING THE SURVEYOR AND MAPPER ERA OF GIS? A Position Statement by David W. Gibson
Many people are questioning the coverage of Chapter 472 Florida Statutes, Surveying and Mapping. Could it be that the legislature really meant that "the improper surveying and mapping of land, water, and space presents a significant threat to the public?" Chapter 472's statutory definition clearly covers any professional service or work involving special knowledge of relevant areas of math, science, and the requirements of law for the determination of the facts of size, shape, topography, orientation, legal location, or geodetic location of features on or near the earth's surface. Later in the chapter, the legislature clearly states, "No person shall practice surveying and mapping unless such person is registered pursuant to ss.472." Is that clear, or is that clear? The terms "professional service or work" seems perfectly clear. You make a 'profession' in surveying and mapping when you declare to the world that you know the relevant specialized body of knowledge known as surveying and mapping and that you will apply it for hire to the benefit of client or employer. The public statement is usually made through the yellow pages, or may also be made by taking on contract or employment work that requires measurement science expertise resulting in a finding of facts of size, shape, orientation, or location that will be relied on by someone else. The term professional 'service' implies that the surveying and mapping expert works for a client, that will innocently trust the accuracy and completeness of the work done. Professional 'work' indicates that the same innocent trust exists in employment situations such as in government when a person holds themselves out for employment in doing surveying and mapping activities. Chapter 472 clearly states that all such 'service' or 'work' must be done or supervised by a licensee of the state. It seems quite clear to me. Perhaps, therefore, it is time to place the current GIS/GPS issue in the context of recent history. CONVERSION IS FADING Early developers of GIS employed cartographic conversion techniques to build computerized spatial models of features on or near the earth's surface. Conversion contractors and services were encountered quite frequently from 1985 to about 1995, but now, use of that term is vanishing. Why? The term 'conversion' implies that a graphical map or written deed simply had to be converted to digital by some cartographic process such as digitizing, scanning, or warping. GIS conversion proceeded so rapidly in the previous decade, that today, most pre-existing useable maps that had any shred of geographic truth have been digitized. Quad sheets are now DLG's. Appraisal property ownership maps are now seamless parcel base maps for counties. Utility schematics are now in overlays over parcel maps. Soil maps are also in overlay files. Now, as we approach the end of the 1990's, could it be true that the GIS community is running out of pre-existing maps to convert? GIS' SILENT PARTNER Was the surveyor a partner in this first decade of GIS? Yes, quite definitely, even though the surveyor and mapper is best described as the "silent partner", because that person's contribution has never been acknowledged. However, let us make the following statement very clearly: ALL GEOGRAPHIC TRUTH IN ANY MAP CAN BE TRACED TO A SURVEYING AND MAPPING PROCESS. Someone at sometime must have directly measured features by one of our surveying and mapping technologies: tape, transit, level, theodolite, aerial camera, scanner, or satellite positioning system in order for any map to have geographic truth. For example, most geographic truth in the property appraiser's "tax maps" can be traced to the accuracy by which the original federal surveyor set out and mapped townships in the 1800's, and to the degree that surveyors from then until now furnished attorneys with measured or computed information for deed calls of recorded plats, bearings, angles, distances, and adjoiners. When these fragments of truth were assembled into ownership maps by the appraiser's mapping staff, the surveyor and mapper's work formed the fundamental basis of truth -- even though the surveyor and mapper's identity did not carry through the deed writing and map compilation process in most cases. The same can be said for USGS quad sheets. From 1920 to 1990 federal surveyors and mappers for the USGS compiled original graphical overlays for quad sheets from field surveys by plane table and later by stereo plotting from aerial cameras using geodetic control structures set by federal geodetic surveyors of the NGS. The geometry of road and railroad systems were painstakingly calculated, laid out, and documented by surveyors and mappers of state, county, city road departments, and the state's railroad companies. Other surveyors and mappers assisted power, water, telephone, and cable utility companies in developing truth in their utility maps. In most cases, digital conversion did nothing to increase the geographic truth in these pre-existing maps. In fact, many times, good map information was degraded by poor digitizing or by converting it to approximate control points, thereby introducing stretching and warping that gave less geographic truth after conversion than the map had before. Yes, surveyors and mappers were definitely partners in the first wave of GIS. Without their carefully produced measurements there would be little truth at all in the converted digital product. MEASURE IS IN So the GIS world faces its future with a startling fact: THE ONLY WAY OF DEVELOPING GEOGRAPHIC TRUTH IN THE UPCOMING YEARS OF GIS IS BY DIRECT MEASUREMENT OF FEATURES. Direct measurement of features is called surveying and mapping. Those who do it are called surveyors and mappers. The global positioning system, GPS, is the next surveying and mapping tool that also just happened to come along during the time period when conversion opportunities in GIS were winding down. Those who did GIS by conversion for ten or fifteen years without speaking to a surveyor and mapper presumed that they could also move into the realm of direct measurement by GPS under the guise of "GIS Mapping". However, our Board of Professional Surveyors and Mappers backed many practicing professionals in questioning this move as infringement on surveying and mapping practice as practiced over thousands of years and as defined in Chapter 472. For the past three years, the GIS community has slowly been wakening up to the pre-existing and continuing profession of surveying and mapping. It is easy to see why Chapter 472 is not popular in GIS circles. No one wants to give up freedom of action by bringing in licensed surveyors and mappers for the next phase of GIS, however, the public will be increasingly reliant on the accuracy of base GIS layers, and surveyor and mappers have a safeguard mechanism in place through the licensing process. SUPERVISION IS THE KEY The Board of Professional Surveyors and Mappers is currently entering negotiated rule making with interested parties to try to find a common sense method of providing supervision of spatial data collection by a licensed person. The League of Cities, Geographic Information Board, and the Florida Surveying and Mapping Society have recently been invited to assist the Board in coming up with supervision language that is reasonable. The goal is to have a licensed person involved in GPS work, not in the field every minute, but from a overall view in writing procedures to be followed, training those doing the measuring, monitoring compliance with prescribed methods, and documenting the data. Maybe there's a way of co-operating on the next wave of GIS after all.
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