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The Big Picture

image of compass rose

Mariners have navigated to and from the Chesapeake Bay since the early days of our nation. Today, the Bay remains a major transportation artery of the United States—containing some of the nation's largest sea ports, airports, railroad hubs, and interstates. In order for ships to navigate safely through the Bay and the U.S. Marine Transportation System, NOAA relies on its newest research vessel—Bay Hydro II—to identify hazards to navigation and collect data needed to keep NOAA nautical charts up-to-date.

Seeing the Sea Floor

If human eyes could see to the bottom of the Chesapeake Bay as they can through air, countless wonders like fish habitats, shipwrecks, and deep canyons would be seen. Bay Hydro II serves as NOAA's "eyes" to the Bay's bottom. The vessel is equipped with state-of-the-art hydrographic technology that calculates water depths, locates sunken debris, and characterizes the shape of the sea floor.

Responding to Emergencies

Accidents and natural disasters do happen—frequently with little to no advanced warning. Bay Hydro II serves as a navigation response unit, equipped to survey for submerged hazards near port entrances and critical shipping routes should an emergency occur. Delays in shipping can cost the economy billions of dollars—and prevent supplies from being delivered to hard-hit regions. Bay area officials rely on NOAA data to make decisions about resuming shipping operations.

Testing New Technology

Before echo sounding technology existed, early American surveyors used ropes and lead weights to survey the Chesapeake Bay. Today, NOAA uses Bay Hydro II as its primary platform to test and evaluate new and emerging hydrographic survey technologies. One such technology that has been tested by this crew in the past is the Autonomous Underwater Vehicle—a torpedo-shaped robot that is programmed to guide itself through the water and collect sea floor data—multiplying the amount of data NOAA's survey fleet collects.

Data for Decisions

In addition to updating charts, the hydrographic data collected by Bay Hydro II is used by coastal managers, biologists, planners, and policymakers to better understand the formation and habitats of the Chesapeake. This allows Bay area officials to make informed decisions about important issues, such as managing fisheries, regulating coastal development, and assessing coastal resources.


Homeport: Solomons, Maryland

Crew: One NOAA Corps officer and two physical scientists, all trained in hydrography

Crew stateroom & galley

Overall Length: 57 feet

Widest Length (Beam): 21 feet

Max. Speed: 31.5 knots (about 35 mph)

Cruise Speed: 25 knots (about 29 mph)

Range: 625 nautical miles

Kvichak Marine Industries, Seattle, Washington