A horizontal control point, third order or better, with a permanent benchmark that includes elevation would be most useful for what?

A horizontal control point, third order or better, with a permanent benchmark that includes elevation would be most useful for what?

• A. It has no elevation data
• B. It includes the elevation value
• C. It marks only the location without height
• D. It indicates a survey boundary only

Answer: (B)

Having a horizontal control point that is third order or better means you have precise horizontal coordinates and a proven level of accuracy for the network. When that point also has a permanent benchmark with elevation, you gain a known height above a datum in addition to its location. That vertical reference is what ties the entire project to a real height, making it possible to perform accurate leveling, establish elevation benchmarks for design and construction, and connect other measurements to a stable datum. Without elevation data, you can locate the point but can’t reference height; a point that only marks location or only signals a boundary doesn’t provide the necessary height information. So, the inclusion of the elevation value is what makes it most useful.

Having a horizontal control point that is third order or better means you have precise horizontal coordinates and a proven level of accuracy for the network. When that point also has a permanent benchmark with elevation, you gain a known height above a datum in addition to its location. That vertical reference is what ties the entire project to a real height, making it possible to perform accurate leveling, establish elevation benchmarks for design and construction, and connect other measurements to a stable datum. Without elevation data, you can locate the point but can’t reference height; a point that only marks location or only signals a boundary doesn’t provide the necessary height information. So, the inclusion of the elevation value is what makes it most useful.