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I was invited to do a 6-month visiting professorship at a distinguished university surveying school named E.S.G.T. (l’École Supérieure des Géomètres et Topographes) in Le Mans France, about 70 miles southwest of Paris. My task was not to teach, but to research how the French do surveying, geomatics, mapping and GIS, and compare with the U.S. methods. One area of my investigation was in boundary (cadastral) surveying.
The French Surveyor
The French licensed surveyor is called a "Geometre-Expert (G.E.)." Of course the word geometre means an "earth measurer". Most applicants today have a very high engineering university education leading to a Masters of Engineering in Geomatics from schools like E.S.G.T. And upon taking and passing an extensive federal exam, they enter the "Ordre of Geometre-Experts (OGE)", and are licensed to practice for the public. Many specialize in boundary surveying.
The National Edge-matched Geo-referenced Cadastre
By studying the national website of the OGE, it became apparent that the cadastral tax department of the French government has an internet site with all land parcels shown geo-referenced to a seamless orthographic aerial photo mosaic. In the U.S. tax mapping process, surveyors have little direct input, and the maps are used only for valuation for taxing. The U.S. ownership decisions are left to the courts, attorney opinions, title searches, and title insurance. However, in France the Internet-published cadaster is used much more as an "absolute cadaster," displaying the true owner along with an accurate map of the parcel.
Also, the French tax department’s cadastral information has significant survey input over the years. Surveyors begin a boundary survey by approaching the tax department, notifying them of the upcoming survey, and then receiving all information the tax department has–previous markers set in the area, the cadastral map, surrounding owners’ names and contact information. The survey is done on the ground, and then an official Government "form" is used to construct a survey map showing the parcel’s geometry, corners set, geodetic corner coordinates. This map and other information are then given to the tax department for their use in updating the official cadastral map. All the information related to the survey is kept in a file called a "dossier" kept by the surveyor, and a duplicate "dossier" kept by the tax office.
The French cadastral map is not 100% survey based. Many parcels are very old without "dossiers" of survey data. As in the U.S., the French cadastral tax department cartographically "sketches in" the non-surveyed boundaries by following old fences, roads, building edges. But as time goes by, these sketched boundaries are rapidly being replaced with direct survey information.
In France, every new parcel MUST be created by field survey. By law there can be no protraction–or "of" parcel divisions such as "the North 50ft of ___", etc. The law requires survey markers to be set at each corner, and the survey "dossier" to be furnished to the tax department. The original monuments control the parcel’s location forever for newly created lines.
Establishing Old Lost Boundaries
The re-establishment of old lost boundaries is handled by a very interesting process–by agreement between adjacent owners–in French called a "Proces-Verbal de Limitation et de Bornage". The French surveyor is the mediator. The surveyor sets up a day and time for an on-site meeting between the owners. The surveyor had previously searched for all original corner markers using distances, boundary features such as fences, etc. Then a verbal process, described below, is used to establish the boundary. The owners are expected to reach agreement in the official field meeting. However, if no agreement is reached, there is a special cadastral (land) court they must go to for resolution. But they don’t want to go to court due to the legal expense and time. It is much easier to reach agreement in the field session.
The line is marked by an official orange colored plastic corner marker called a "borne" and the collection of all monuments is termed "bornage." All French surveyors must use the same standard "borne."(See below) A 2-ft long steel rod is driven through the plastic center to mark the point, and then the orange plastic’s top is lowered to ground level covering the top part of the rod. The orange plastic just makes the rod’s location visible for years.
After the agreed corners are set, the survey technicians return to measure the property–today probably using GPS to measure and geo-reference the corner locations. The survey map is made and the map and dossier are then furnished to the tax department, and the cadastral map is updated.
A Real Survey Example
While browsing the cadastral map in the Le Mans area, I noticed that a local French surveyor was responsible for a "dossier" on a parcel. That surveyor seemed to be very prominent–Pierre Guillerminet of Le Mans. Using the street address given, I stopped by his office to introduce myself and have a brief talk. His English was partial, and my French was likewise, but we could communicate alright. After a brief discussion, I said that I would like to "go in the field" to see a real French survey process. Without hesitation, he asked me to meet him at the Eglise (church) in a small rural village about 20 miles north of Le Mans at 2:20PM (14H20) on the upcoming Thursday afternoon.
On that day, I drove into the village with houses looking 200+ years old. Of course every French town has a church with a high steeple at the town center. Following the narrow streets toward the steeple, I arrived about 10 minutes before Pierre. In another 5 minutes, his survey technician arrived. I jumped into Pierre’s car and we arrived at the survey site on the edge of town to find about 6 people standing waiting for us–(1) the husband/wife of one parcel being a very nice new home built within the past 3 years, (2) the husband/wife of a small farm plot east of the first parcel, (3) a single man owner of a large farm further away, and (4) the mayor of the small village, who was there due to the location of easements for buried storm water drainage pipes. The main job was to set the boundary (about 500ft in length) between the two husband/ wife owners so the cadastral map could be fixed. The cadastral map showed some ancient location for the boundary which was obviously incorrect.
Then the survey technician set a red/and white survey pole at a proposed boundary point. After much discussion, the pole was moved and moved. Pierre asked, "Do you now like this location?" Once both owners responded "yes", the technician pulled up the pole and set a "borne" at the agreed point. Then the group walked down the line to the next discussion area, and the process was repeated. After several agreed points were set on the boundary, each owner then had to sign an official government cadastral document, with each saying that they agreed on the set points, and they cannot reverse the agreement. Notice that each owner could not have their own surveyors or attorneys present, just the one French surveyor as a confidential mediator.
Conclusions
This experience showed me the high public visibility and standing of the French surveyor. The French public knows that the government’s cadastre is nearly an abso
lute statement of ownership, and that the cadastre can be directly modified with surveyor input. It is viewed that the private practitioner is a direct extension of the government’s cadastral department’s authority. This respect is increased by practitioners having a Masters in Geomatics Engineering degree. This is clearly shown in the confidence placed on the French surveyor as a boundary mediator.
Prof. David Gibson has been teaching surveying and geomatics since Fall, 1968 and has been at the University of Florida since 1974. He began and directed the geomatics programs at UF. His degrees are from the University of Cincinnati, the University of Miami, and the University of Alabama.
A 3.827Mb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE