![NOAA Ship Fairweather sailing in Alaska with mountains in the backdrop. NOAA Ship Fairweather sailing in Alaska with mountains in the backdrop.](images/survey-vessels/fairweather.jpg)
NOAA Ship Fairweather
![Sun setting on NOAA Ship Rainier with Mount Baker in the background. Sun setting on NOAA Ship Rainier with Mount Baker in the background.](images/survey-vessels/rainier.jpg)
NOAA Ship Rainier
![NOAA R/V Bay Hydro II underway. NOAA R/V Bay Hydro II underway.](images/survey-vessels/bay-hydro-ii.jpg)
Hydrographic Ships
NOAA operates four large ships dedicated to hydrographic surveying: Fairweather, Ferdinand R. Hassler, Rainier, and Thomas Jefferson. Each ship is equipped with the latest echo sounding technology to measure water depth and identify submerged hazards to navigation. Each ship has 1-6 smaller boats (called launches) that are lowered into the water for surveying in shallow areas.
Coast Survey’s research vessel Bay Hydro II, based in the Chesapeake Bay, also conducts surveys. It shares many of the features of the larger ships, and has additional responsibility to test and evaluate new hydrographic survey technologies.
Coast Survey deploys six navigation response teams equipped with small boats that generally survey port areas. These two- or three-person teams may be mobilized from their normal duties to respond to port closures after hurricanes and other emergencies.
Revised: 8/11/2020