Reference coordinates on a site plan refer to distances from what?

Reference coordinates on a site plan refer to distances from what?

• A. A pre-determined datum or benchmark
• B. Geographic north
• C. The equator
• D. A local street reference

Answer: (A)

Coordinates on a site plan are measured from a fixed starting point, a datum or benchmark, which defines the coordinate system for the whole plan. This fixed origin lets every feature’s x and y values be consistent and repeatable when you move from drawing to field survey, ensuring accurate placement. A benchmark provides known coordinates (and elevation) that tie the plan to real-world space, so all measurements relate back to that fixed point. Other options don’t fit because geographic north governs direction (bearings), not the origin for coordinates; the equator relates to latitude, not a local survey reference; and a local street reference isn’t a universal, fixed origin used to position everything on the plan.

Coordinates on a site plan are measured from a fixed starting point, a datum or benchmark, which defines the coordinate system for the whole plan. This fixed origin lets every feature’s x and y values be consistent and repeatable when you move from drawing to field survey, ensuring accurate placement. A benchmark provides known coordinates (and elevation) that tie the plan to real-world space, so all measurements relate back to that fixed point. Other options don’t fit because geographic north governs direction (bearings), not the origin for coordinates; the equator relates to latitude, not a local survey reference; and a local street reference isn’t a universal, fixed origin used to position everything on the plan.