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Hydro Survey mission a key part of harbor operations

Hydro Survey Team

USACE Savannah District Boat Captain, Eddie Culp, of the survey vessel Downs, and district Civil Engineer technicians Kenneth Skinner and Michael Ansley conduct a survey in the Savannah River. The team ensures the Hydro Survey section helps keep the nation’s commerce flowing.by keeping the ports of Savannah and Brunswick open with their surveys.

Analyzing survey data

USACE Savannah District Civil Engineer Technician, Kenneth Skinner, monitors the data from a cross section survey across the Savannah Harbor channel. These cross sections are used to compute the volumes of material in the channel.

Boat Captain

USACE Savannah District Boat Captain, Eddie Culp, of the survey vessel Downs, pilots his boat during an after dredge survey of the Savannah River. Culp is part of a team that ensures the Hydro Survey section helps keep the nation’s commerce flowing by keeping the ports of Savannah and Brunswick open with their surveys.

sound velocity profiler

USACE Savannah District Civil Engineer Technician, Michael Ansley, explains the use of a sound velocity profiler. The device helps calibrate the fathometers before a survey by measuring the variables affecting sound velocity in water; salinity, temperature and pressure variables.

The Brunswick and Savannah Harbors are essential to supporting the nation’s commerce. The U.S. Army Corps of Engineers Savannah District Hydro Survey section has responsibility for ensuring these and other waterways remain passable.

The survey section performs many types of surveys, but the type done most by the Savannah District are before-and-after dredge surveys.

“Before dredging begins, we do a sonar scan of an area, and that gives us a starting elevation or depth,” said Chris Wheeler, hydro survey section chief, Savannah District Navigation Branch. “After dredging operations are done in an area, we go back within two to five days, do another sonar scan of the river depth, and difference is how we calculate how much the dredgers are paid for their work.”

The survey section is staffed by six people and is assisted in their mission by three boat captains stationed at the District’s depot on Hutchinson Island across from downtown Savannah.

There are three main areas that the district survey section covers: the 40 miles of the Savannah harbor; 28 miles of Brunswick harbor and 162 miles of the Atlantic Intracoastal Waterway running from just south of Hilton Head, South Carolina, to Kings Bay, Georgia.

“For the out of town trips that require multiple days for our large boats, we take the vessels down the first day, or sometimes the day prior, and dock them at a private marina just like you would pay for parking in a parking garage,” said Jonathan Broadie, Operations and Asset management section chief, Savannah District Navigation Branch. “The teams then operate from there for the rest of the trip until they can return to the depot.”

The section also does surveys annually of the Altamaha (137 miles), Ocmulgee (255 miles) and Oconee (221 miles) Rivers.

“That’s part of our project conditions survey mission,” said Broadie. “Those three rivers used to serve a federal navigation purpose, but even though they no longer do that, the federal government is still interested in surveying them periodically to determine their condition.”

The current COVID-19 pandemic has affected the Savannah District just as much as it has the rest of the world, but because of the critical nature of areas like Savannah Harbor, the survey section adapted their operations to continue the mission.

“The engineering regulations that govern our survey mission give us the flexibility to adjust based on our knowledge of the harbor,” said Broadie. “Since we have this knowledge of how the river behaves and the areas that it shoals, we are able to alter our mission frequency to limit the exposure of the teams during this time.”

Where normally a survey of an area such as Brunswick Harbor would take a day or two, under current conditions, that same survey takes most of a week.

“On these survey vessels they have to work closer than six feet apart for extended periods, so in order to minimize their risk and exposure to one another we’ve adjusted the schedules for surveying of the critical areas that we cover,” added Broadie.

On some of the smaller boats the cabins aren’t even six feet wide, but the survey section has procedures in place to be able to continue the mission.

“We wear masks at under six feet, all vessels are disinfected as they’re boarded as well as upon disembarking and we are monitoring all personnel for possible symptoms,” said Wheeler. “We’ve also cut back on some of our daily maintenance. We’re only performing required maintenance and if it’s not an active survey day we’re teleworking in order to distance as much as we can.”

The boat crews are taking the new procedures and integrating them into their daily operations as part of the ‘new normal.’

"Going forward, I don’t see any change to what we’re doing as long as the COVID issues are in place,” added Wheeler. “We’re just taking it day-by-day. We are an essential mission for the harbor, and the harbor’s not closing.”