Certified Floodplain Manager (CFM) Practice Exam 2026 – Complete Preparation Guide

The NGVD, or National Geodetic Vertical Datum, is known as the Mean Sea Level Datum of 1929 today. This datum serves as a consistent reference for measuring elevations and depths across various geographic areas in the United States. Specifically, it is based on the mean sea level observed at various tide gauges throughout the U.S. in 1929 and provides a standardized baseline for elevation data, which is crucial for floodplain management, engineering, and surveying.

The significance of the NGVD is highlighted in floodplain management as it helps determine flood elevations, enabling effective planning and mitigation strategies. Understanding this datum is critical for professionals working in floodplain management, as it informs decisions related to zoning, construction, and emergency response in flood-prone areas.