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NOAA Air Gap Information Saves Cruise Traffic

April 18, 2011
A cruise ship approaches the Dames Point Bridge in Jacksonville

A cruise ship approaches the Dames Point Bridge in Jacksonville, Fla. In the foreground is an air gap system, a tool that measures the clearance between the water surface and the bridge.

In January, NOAA received a request to install an air gap measuring system on the Dames Point Bridge in Jacksonville, Fla. The air gap system is a tool that measures the clearance between the water surface and a bridge.

Due to a bridge maintenance project by the Florida Department of Transportation (FDOT) on the Dames Point Bridge, the air gap, or bridge clearance, was reduced. Carnival Cruise Lines expressed concerns about this reduction because of the small clearance already experienced by cruise vessels, and considered moving their business unless there was an accurate measurement of the clearance. Ship captains need updated, accurate clearance data to safely navigate vessels under this bridge.

In response to the request, NOAA and FDOT installed an air gap system on April 8, and are now providing bridge clearance information to Carnival and other large vessels transiting under the Dames Point Bridge.

The response to this request will support the cruise ship business which generates $3.4M in revenue for the Port of Jacksonville, not to mention the economic impact to the local community.