Blog
What the drawing shows, how it differs from a boundary survey, and who needs one.
Most surveys answer the question "where are my lines?" A topographic survey answers a different one: what shape is this ground in, and what is already on it? The result is a scaled drawing built from three kinds of information:
Contour interval is the vertical distance between one contour line and the next. On a one foot interval, each line you cross represents one foot of rise or fall. The interval is a choice made for the project, and it governs how much the drawing can tell you.
The effect shows in how the lines space out on paper. Where ground is steep, contours crowd together, because a foot of elevation is gained across a short horizontal distance. Where ground is nearly flat, they spread far apart. That is why a flat site mapped at a coarse interval can look featureless while still holding the fraction of a foot of fall that decides which way water runs.
A tighter interval resolves smaller changes; a coarser interval reads more cleanly across a large tract. Which one serves you depends on the design, which is why the interval is settled with the engineer or architect before fieldwork begins.
The two get confused because both end in a drawing of your property. They answer unrelated questions.
A boundary survey is a legal exercise. It reconstructs your property lines from deeds, recorded plats, and evidence found on the ground, producing a plat that speaks to where your ownership begins and ends. It is the survey behind a fence line or a closing.
A topographic survey is a physical one. It carries no opinion about where your lines run. It describes the surface: heights, slopes, the paths water takes, and the improvements already in place.
They are frequently ordered together, because most design and permitting work needs both. Placing a building means respecting a setback measured from a legal line and the terrain the structure sits on.
The thread running through all four is that each is making a decision the ground can veto. Grade is not a detail added at the end of a design. It sets how much earth has to move, where water collects and where it leaves, whether a driveway can meet its slope limit, and whether a building fits where the owner pictured it. A design drawn over assumed terrain gets corrected in the field.
Georgia is divided into physiographic provinces, and the northwest corner of the state sits in the Ridge and Valley. Folded sedimentary rock, eroded at uneven rates, produced the region's pattern of long parallel ridges and valleys. Ridges hold their height on harder sandstone and chert; valleys are cut into softer shale and limestone. Floyd County is almost entirely Ridge and Valley, Gordon County nearly so.
South and east, the Piedmont takes over: rolling upland without the long parallel structure. Haralson and Paulding counties are effectively all Piedmont. Polk County straddles the two, with a Ridge and Valley majority and a Piedmont southern portion. Bartow County is the complicated one, with three provinces meeting inside it and the greatest local relief in the region, roughly 1,464 feet.
For a specific site, that variety is the argument for measuring rather than assuming. A parcel on a limestone valley floor and one on a sandstone ridge a few miles away present different grading quantities, drainage patterns, and stormwater problems.
The deliverable is a drawing, and the file format matters as much as the content. A topographic survey is normally delivered as a CAD drawing with a PDF. The PDF gets printed, marked up, and passed around. The CAD file is what the design team works in: your engineer opens the topo as a base layer and draws the proposal on top, so proposed grades and pipe runs sit over measured existing conditions rather than estimated ones.
That base map feeds what follows. A site plan submitted for a permit shows a proposed layout against conditions already on the ground. An erosion control plan depends on knowing which way water moves and where it leaves the property, a question only elevation data answers.
S&S Land Surveying prepares topographic surveys from its Cedartown office, with a licensed Georgia surveyor and more than 40 years of surveying experience behind the work, covering Polk, Floyd, Bartow, Paulding, Carroll, Haralson, Douglas and Gordon counties along with the wider Northwest Georgia and metro Atlanta region, including Rome, Cedartown, and Cartersville.
A contour line connects points at the same elevation, showing the general shape and slope of the ground. A spot elevation is a single measured height at one exact point, used where precision matters, such as a slab corner, a pipe invert, or the crown of a road.
The interval is normally set with the engineer or architect who will use the drawing, based on what the design has to resolve. A tighter interval shows smaller elevation changes, while a coarser interval reads more cleanly across a large tract.
No. A topographic survey maps physical features and elevations and does not establish legal boundaries. Property lines are determined by a boundary survey, which reconstructs them from deeds, recorded plats, and evidence on the ground.
Call us today at 678-873-3119 or request a free estimate online.