Ocean floors are always changing. Coast Survey’s hydrographic surveys are intended to find and measure those changes. Often, we need to do more than that, as shown by a recent survey of the seafloor in Alabama coastal waters.
A Coast Survey contractor ‒ David Evans and Associates ‒ found a large high-pressure natural gas pipeline that had been uncovered and was lying exposed, as shown by this side scan sonar image. The exposed 36-inch diameter pipeline, pressured to 2,100 psi, posed a threat to navigation and the environment.
NOAA navigation manager Tim Osborn worked in concert with the contractor to report the danger to the Department of Interior Bureau of Ocean Energy Management (BOERME), and to the U.S. Coast Guard District 8 Headquarters Waterways Section. Tim and the contractor were able to provide precise positions, imagery, and other resources.
The Coast Guard is warning mariners to avoid the area.
The pipeline delivers over 1.3 billion cubic feet of natural gas per day to the 20 million residents of Florida. In addition to posing a threat to the marine environment, an accidental rupture of the pipe could cause a national economic impact in losing a huge supply of energy.