Vertical Datum Used for Flood Mapping in Puerto Rico An Application in the Bayamon River Basin

Abstract

Inconsistencies in the use of different datums used for the creation of the Bayamón River basin flood maps force some land surveyors, cartographers, and other professionals working with flood maps, to use the USGS MSL of 1927 datum, while others use the NGS PRVD 02 datum as a vertical reference surface. The objective of this study is to explain the current situation in addition to promote a better understanding of which vertical datum should be used when working with the flood maps of the Bayamón River basin. A methodology is established that could aid the professionals working with the current FEMA flood maps in the Bayamón River basin. Key Terms - Datum, flood insurance rate map, flood insurance study, mean sea level.