Fast response squads keep coast clear

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After hurricanes and other disasters, they work quickly to open waterways for vessel traffic

After hurricanes and other disasters, they work quickly to open waterways for vessel traffic

Three days after Hurricane Katrina vented its fury on the Gulf Coast in August 2005, NOAA teams were on the water surveying the navigational channels into New Orleans, Mobile, Ala., and other ports, identifying wrecks, marking uprooted trees and locating downed range markers, industrial tanks and other bottom debris.

Though the mission of these Navigational Response Teams is to open waterways as quickly as possible to commercial traffic, pleasure boats benefit from their work as well, says Tim Osborn, 49, of Lafayette, La. The teams work with the Coast Guard and Army Corps of Engineers to get commercial ports, military bases and fuel terminals open again for oil tankers, which play a critical role in fueling the post-hurricane recovery; carriers loaded with coal for power plants; military vessels; and other large commercial ships.

“We find everything out there,” says Osborn, who as NOAA’s eastern Gulf navigation manager helped chart channel bottoms in Louisiana, Alabama, Mississippi and Texas after back-to-back hurricanes Katrina and Rita.

NOAA teams — four in 27-foot aluminum workboats and others on the hydrographic survey ship Thomas Jefferson and oceanographic vessel Nancy Foster — found sunken barges and grounded ships, holed sailboats and motoryachts, industrial tanks, chunks of homes, extensive shoaling, and lots of shipping containers. Hundreds of containers stacked in Gulfport, Miss., a major port of entry for fruit and vegetables, floated away in Katrina’s surge. “We found them in town and scattered all over offshore,” Osborn says.

Within two weeks of Katrina, the Mississippi River navigation channel from Baton Rouge, La., to New Orleans and most Gulf ports — New Orleans, Mobile, Pensacola, Pascagoula, Biloxi, Fourchon and Lake Charles — were open again.

NOAA has predicted a more active than usual hurricane season this year, with 12 to 16 tropical storms (11 is average), six to nine hurricanes (six is average), and two to five hurricanes Category 3 or higher (two is average). With hurricane season under way and most storm activity predicted for August through October, NOAA has six NRTs prepositioned around the country for hurricane and other emergency duty, says Lt. Cmdr. Lawrence Krepp, chief of NOAA’s Navigation Response Branch. One is in Charleston, S.C., for quick response in the Southeast, and another is in Pensacola, Fla., in the eastern Gulf of Mexico. The Bay Hydrographer, a converted 55-foot Navy minesweeper trainer berthed in Solomons, Md., also is available for emergency survey work.

Osborn says a team usually can be on-site within a day, but the water often is too silty until at least two days after a hurricane’s landfall to effectively use sonar for mapping, and finding access to the water for their trailerable 27-footers can be daunting. In Texas, the navigation team had to enlist bulldozers to clear dead cattle from a launch ramp before they could launch their boats. After another storm, they had to wait 18 hours for the surge to turn before they could launch.

NRTs typically launch with a crew of three — coxswain, sonar operator and watchstander. Teams use side-scan sonar to capture imagery of large swaths of bottom and get a rough idea of what’s there. A multibeam sonar can be used to obtain accurate depths over objects and give a three-dimensional image of them. NRTs can gather images and precise measurements, depths and locations of debris with sonar and GPS, but unless an object has a distinct shape, like a boat, the team probably won’t be able to tell what it is unless they send a diver down.

Osborn says after Katrina NOAA worked with Navy salvage ships, which put divers down — sometimes as soon as a day after charting — to get a closer look at debris so the Coast Guard Captain of the Port could decide whether to leave it, raise it, move it or put temporary buoys out and route traffic around it. “During a response, we look at ourselves as working for the Coast Guard,” Krepp says. “We’re responsible to the Coast Guard Captain of the Port in any given area.” They also assist the Army Corps of Engineers, which is responsible for the nitty-gritty work of dredging and clearing the channels.

After a day of sonar work and charting, the team goes back to a mobile trailer, where they download the data to a computer, which processes it and sends it on to NOAA. Any hazards to navigation are then forwarded to the Coast Guard for broadcast in a Notice to Mariners and publication in digital “chartlets,” which go to the Captain of the Port and pilots association. If a hazard isn’t removed, information about it is incorporated later into chart updates.

A NOAA team continues to survey and chart the waters of Alabama, Mississippi and eastern Louisiana — both inshore and offshore — for debris from Katrina. So far they have identified 5,000 objects. Some are hazards and will be removed; others, though hazards, will stay and be noted on future charts. Downloadable charts showing the locations of all of this debris, plus lists and locations of the hazards, are available at NOAA’s Gulf of Mexico Marine Debris Program Web site (www.gulfofmexico.marinedebris.noaa.gov ).

“There’s a whole lot of shoreline that got beat up from that storm,” Krepp says.

When the NRTs aren’t responding to emergencies, they travel from port to port verifying water depths, locations of aids to navigation, and visual references as a quality check of information on electronic and paper charts.

“They do stay busy,” Krepp says. “There’s a lot of shoreline in the United States.”

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