Why are survey control points included in hydrographic surveys?

Survey control points are included in hydrographic surveys primarily to allow the survey to be tied to other maps or surveys. These control points serve as reference marks that provide a fixed position on the earth's surface. By establishing these points, surveyors can ensure that the hydrographic data they collect—such as water depths, underwater features, and navigational routes—can be accurately integrated with existing geographic information systems and other survey data.

This connection to other maps or surveys is vital for various applications, including navigation safety, resource management, and environmental monitoring. Control points allow for the alignment of hydrographic survey data with topographical maps, making it easier to interpret changes in both land and water environments and ensuring that all data stakeholders are working from a consistent framework.

The inclusion of control points is a fundamental aspect of ensuring the integrity and usability of the survey data over time and across varying projects.