NCEES Principles and Practice of Surveying Practice Exam

What is a Principal Meridian?

1. An east-west running line

2. The main imaginary line running north and south

3. A line marking local property boundaries

4. A boundary line between townships

The correct answer is: The main imaginary line running north and south

A Principal Meridian is fundamentally defined as a main imaginary line that runs north and south. It serves as a key reference line for land surveying in the Public Land Survey System (PLSS) commonly used in the United States. The Principal Meridians are established to delineate land parcels in relation to geographic coordinates, facilitating the systematic survey and division of land. These meridians correlate with baselines, which run east-west and intersect with the Principal Meridians at specific points. This system allows for the creation of townships and ranges that define land areas, streamline land acquisition, and provide a basis for property boundaries. Understanding the concept of a Principal Meridian is crucial for surveyors, as it aids in accurately mapping and referencing land parcels based on the national grid system.