Bathymetry of Hog Island Bay, VA 2022

The bathymetry of Hog Island Bay, VA was surveyed in summer 2022 using a CEESCOPE Hydrographic Survey System with a boat-mounted single-beam transducer. The ping rate of the transducer was 20 Hz and it had a factory-stated accuracy of up to 1 cm +/- 0.1% of depth. Positioning was determined using a NovAtel RTK GNSS receiver. The data was collected and processed using Hydromagic hydrographic survey software by Eye4Software, which georeferences depths with RTK positioning to determine the latitude, longitude, and elevation of each data point relative to NAVD88, thereby accounting for effects of tides and other sources of water level variation during the survey. Elevation uncertainty of the point data was determined by comparison with two independent digital elevation models generated using Structure-from-Motion photogrammetry at two different bay-marsh boundary sites in the bay. Elevation uncertainty was 0.049 m based on the root-mean-square-error between the datasets.
Coordinate system: NAD83 / UTM zone 18N (EPSG: 26918)
Vertical Datum: NAVD88 using GEOID18
The hib_nn.tif raster used a natural neighbor interpolation of the point data at 50 m resolution