02/12/2023
I'm sharing this from a surveying Facebook group. It addresses questions that land surveyors get almost daily including why do I need a survey and how accurate are property lines based on GIS data (including hunting apps, tax map data or the county website). It also goes into the behind the scenes work that is performed beyond what you see us do while at your property.
"Why should I have my land surveyed - public at large often asks?
As opposed to trusting GIS databases or my real-estate agents' opinions.
Many GIS systems including those which realtors use are approximate. Depending on an area, it can have differences of few feet to few hundred feet. Much of it can depend on property size, but also on history of the area.
This is not accounted for in GIS systems because their purpose is not meant to show precise and accurate property boundaries. Their purpose is to get you to the vicinity.
When you are planning on adding to your property, for example, a sunroom addition, a pool, placing a fence or expanding a driveway, you have to get a building permit. To get a building permit your proposed plan has to confirm to California building code and many other governing laws, including zoning ordinances which determine property setbacks. These dimensions need to be rather precise. In most cases +/- 1 foot is not precise enough. Required precision is closer to +/- 0.1 foot. Accuracy too is an issue which non surveyors are not trained to address.
Another common reason when residential property owners need to know where their property boundaries are hostile neighbors.
In both cases, you need a surveyor licensed to practice in your state.
To address the first concern, the precision. Land Surveyors are the only ones who have the training and the equipment capable of measuring land at that level of precision and guarantee accurate results. There is a lot more to measuring than just taping a line on the ground. Each circumstance requires specific methodology and the ability to explain that methodology so that your contentious neighbor cannot easily challenge it in an argument. Not only are Land surveyors the only ones that have this training but are also the only ones allowed by law to do it. (because of the specialized training)
Second concern is legal standing. When you are retracing property lines, you are not just measuring, you are also reviewing the entire body of evidence surrounding specific property location so that it can be defended in the court of law. There is evidence and decisions that even lawyers cannot make without a surveyor. When your land is surveyed, the survey has legal standing. While surveyors do not practice law, their opinion on boundary location evidence is admissible in courts.
Your Realtor, GIS databases, Architects and Civil Engineers licensed after 1982 cannot offer this. Your Landscape Contractor, your General Contractor, your Pool guy, or your neighbors' computer savvy kid cannot offer this. Using sources other than Land Surveyors to locate property boundaries is a good way to end up in litigation.
Yes, a properly done boundary survey can be expensive. From about $2500 dollars to $15,000 or more depending on size, history and complexity. However, land litigation or having to demolish ill placed improvements is exponentially more expensive."
