The U.S. Army Corps of Engineers (USACE) performs hydrographic surveys (hydrosurveys) for federal navigation projects around the U.S. Federal navigation projects include an estimated 25,000 miles of channels and form a key part of U.S. maritime infrastructure in both coastal and riverine areas. Hydrosurveys provide information about channel bathymetry which is critical for safe navigation by mariners, as well as a historical record of how channels change over time due to sediment deposition (shoaling) and sediment removal (dredging). The USACE eHydro program provides a standardized archive of available hydrosurveys from across the country all in one place. The USACE eHydro website includes the ability to search on a map to see where hydrosurveys are available, and when the most recent survey was conducted – an important detail since not all channels are surveyed with the same frequency. Users can download the latest PDF Plotsheet for a channel, or download the underlying data for use in other geospatial software programs.
USACE Hydrographic Surveys page on Data.Gov: https://catalog.data.gov/dataset/usace-hydrographic-surveys
USACE Hydrographic Surveys Main Page with Interactive Map: https://www.arcgis.com/apps/opsdashboard/index.html#/4b8f2ba307684cf597617bf1b6d2f85d
USACE Hydrographic Surveys Data Download Page: https://geospatial-usace.opendata.arcgis.com/datasets?group_ids=df70bc1371e3468b902e657cd26fc91c