Boundary Surveying


Boundary surveying is the branch of land surveying in which a licensed surveyor establishes the boundaries of a parcel of land on the ground.  In all states in the U.S. a surveyor must be licensed by the state as a Professional Land Surveyor before he or she can be retained by a client to establish their boundaries. In many states civil engineers may not engage in activities relating to the description or establishment of boundaries unless they are also licensed as a land surveyor.

Types of Boundary Surveys. 

There are two basic types of boundary surveys: Original Surveys and Retracement Surveys.  An original survey creates new boundaries.  A retracement survey is simply a survey of a parcel of land that has already been created by an original survey.  The image below shows a parcel of land that was divided into 6 parcels or “Lots”.  When the surveyor first created these lots and drew the plan the survey of the lot interior boundaries would have been an original survey.  Assume that all 6 lots were sold to different people  Assume you own lot number 3 and can’t find the corner markers of your lot.   When you retain a surveyor to set your lot corners, the surveyor will perform a retracement survey.  It cannot be an original survey because your parcel is already in existence.  There can only be one original survey – the survey that originally created the 5 lots. An original survey fixes boundary corners on the ground forever and these corners are not subject to relocation even by a court of law.

Retracement Surveys

In most cases, if you own a parcel of land and you need a survey in order to know where your lot corners are located on the ground you will probably need a retracement survey.

In a retracement survey, the new surveyor must locate the boundaries at their original locations, meaning the locations where the original surveyor set the original corners on the ground.  It is said that a retracement surveyor “follows in the footsteps of the original surveyor”. Because physical monuments that mark boundary corners become lost or disturbed over time, and because a retracement surveyor is required by law to set the corners at exactly the same place the original surveyor set them, retracement surveying is often difficult, time consuming and it can be expensive. It is often the case that a surveyor will not know at the beginning of the retracement survey how difficult it will be to find the lost corners until the work is started and an investigation of the deeds, plans and monuments on the ground has been made. In many cases when the original survey is an old survey the work may not have been performed with the accuracy and precision of modern surveys and the passage of time will have taken its toll on the original monuments so many of them may now be missing or disturbed.

When original corners are lost or disturbed the retracement surveyor must know and follow certain legal rules which will affect how the corner locations are reestablished.  If the retracement surveyor does not follow applicable legal rules, the corners set during the retracement survey may not actually represent their true original locations and both the property owner and surveyor may be subject to liability.


It is important to understand that even though modern surveyors can measure a mile within fractions of an inch that does not necessarily mean that a lost boundary corner can be located on the ground with a high degree of confidence. When there are conflicting deed elements or ambiguities in the description there may be substantial uncertainty in the corner locations. Understanding the legal principles which need to be applied in such cases is crucial because it is often necessary to reject certain terms in a deed description and accept others and this has the potential to substantially alter corner locations from an improperly interpreted deed description. It has been said that discipline of boundary surveying is 10% science and 90% law.

How a typical survey is performed.  The first thing that a surveyor does before going into the field it to obtain copies of the deed of the parcel to be surveyed and the deeds of all abutting properties. If the parcel to be surveyed is in a city block, the surveyor will most likely have to get copies of all of the deeds in the block.  This is because the location of the streets making up the block are fixed on the ground and the sum of all of the deed distances between the streets may not add up to the actual measured distance between the streets.  Here again, if such a discrepancy does exist the surveyor will need to be familiar with legal precedent in the jurisdiction and apply the applicable legal rules in order to arrive at the legally correct boundary locations. If the survey is not in an urban area the surveyor will still need copies of the applicable deeds and plans pertaining to the description of the property to be surveyed and the abutting properties. It is usually necessary for a surveyor to trace the current deed description, and probably those of the abutting properties, back to the original survey. This is particularly important when the property has changed hands many times because mistakes are sometimes made when copying the old deed description to the new deed so the current deed may not accurately describe the boundaries. It is the original deed (the original survey) that usually controls not necessarily the existing deed. Of course, it is always possible that there were conveyances from the original deed description which changed the boundaries after the original survey.

Once the surveyor has all of the relevant deeds and plans the surveyor will go out into the field to look for the physical evidence called-for in the deeds.  For example consider the image which shows a division of land into 6 lots. If you owned parcel 2-A and wanted to know where your lot corners were located on the ground you would need to retain the services of a land surveyor. In order for a surveyor to be able to establish your corner locations the surveyor would obtain a copy of the plan shown in the image and a copy of your deed. Your deed would presumably reference the plan as the survey from which your parcel of land was created. In order for a surveyor to locate your boundaries on the ground the surveyor must be able to find enough original physical evidence (monuments) on the ground called-for on the plan and/or your deed. Notice in our example that the plan calls for a number of monuments such as “DH in BLDR” and “C.B.” These notations refer to physical evidence that existed on the ground at the time of the original survey. If these monuments are still in existence and they are undisturbed, and there are no errors on the plan or deed, it should be possible to survey the property with a reasonable degree of certainty. If the monuments have disappeared or have become disturbed, the survey could turn out to be difficult and there may be a high level of uncertainty in the corner locations. It is important to understand that, in general, the only monuments that control boundary locations are the monuments that are called for in the deed or a plan referenced in the deed. Just because there are monuments on the ground which appear to be near boundary corners does not necessarily mean that they can be relied upon for the purpose of fixing the boundaries of a particular parcel of land.

Traverse Lines.  Because many property lines run along fences or walls which act as obstructions making it difficult to measure along the lines, it is usually not convenient for surveyors to try to measure exactly along the boundaries.  Surveyors solve this problem by running “Traverse Lines”.  Traverse lines are simply offset survey lines that a surveyor runs where there is a clear line-of-sight (no obstructions) between the traverse corners.  The traverse lines are shown as red dashed lines on the image below.  The traverse corners are numbered from 1 to 5.  You can see that the traverse lines are in the general vicinity of the boundary lines but they are located so as to miss obstructions.  Notice that line 3-4 was located in order to clear both buildings.  Once the traverse lines have been measured, the traverse points (numbered 1-5) can be used to set the actual lot corners.  The short dashed blue lines, for example 5-D, show the connection between the traverse corners and the boundary corners.


Lot Surveys

We perform many surveys of small lots located in urban areas. These surveys present their own unique set of challenges. In many cities the streets are monumented, usually with stone markers. These monuments fix the street lines which abut private property so they are usually the first place a surveyor looks when beginning a survey of private property in the city. Many of these monuments were set during the 19th and early 20th centuries. The monuments are usually located at street intersections near the back edge of the sidewalk. In many cases the sidewalks have been replaced and the original stone monuments destroyed or covered over during the construction of the new sidewalks. In such cases it may be necessary to extend the survey for several city blocks until a sufficient number of monuments have been recovered.


Boundary Disputes

Boundary disputes arise when abutting property owners do not agree on the location of a common boundary. There are many reasons why this might occur. However, in our experience there are a few common situations. One example is when one of the abutters retains a surveyor to stake out a property line, for example for the installation of a new fence. When the stakes are set on the ground, the other abutter finds that the stakes do not agree with the boundary line that they had been using for many years. Surveyors and attorneys often refer to this situation as the “record” location of the boundary does not agree with the “line of occupation”. In other words, the boundary as described in the deed does not agree with some physical evidence of occupation on the ground. This could be a wall, fence, edge of a driveway or simply the edge the grass that one of the abutter has mowed for many years. When the record location of a boundary does not agree with occupation there may be a valid claim of adverse possession. If so, adverse possession may override the record location.

Another common situation is when an abutting property, that had been owned by many years, is sold to a new person and the new person has their own ideas about where the boundary should be. In such cases it is not uncommon that, prior to the sale, the two abutters had lived next to each other for many years and respected each other’s privacy so the issue never came up. The new owner, having no history, may not be as gracious as the prior owner. Sometimes the new owner is simply aggressive and thinks he can “bully” the abutter into “giving up some land” or cut down some trees or shrubs on the neighbor’s property to open up their own yard. Of course, none of this actually changes the boundary location.

Whatever the reason, the situation often escalates to the point where there is a dispute. Sometimes the dispute rises to the level of threats where the police must be summoned to keep the peace. The police often will not take any action unless there was an actual crime allegedly committed such as assault or criminal trespass. Boundary location disputes are usually civil matters not criminal matters so the police are often not able to take any action other than to warn the abutters not to enter into an altercation. Besides, police usually have no way of knowing where the actual boundary is located and who is right and who is wrong.


When we receive a call from a prospective client about a potential encroachment or trespass by an abutter, particularly when it appears that the abutter may likely damage the client’s property, there are certain steps that can be taken such as having the abutter served by a sheriff with a “No Trespass” order. Other possibilities are seeking a restraining order or a harassment protection order from a court.

If you are interested in learning more about the fascinating subject of boundary surveying you may want to read one of the inexpensive books by Paul L. Gay on land surveying. If so, a good place to start would be Land Surveying Simplified 2nd Edition. The book is available from Amazon.

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