Our country’s marine transportation system is an essential driver of the U.S. economy. Every day, U.S. ports and waterways handle millions of tons of domestic and international cargo ranging from agricultural products to heating oil and automobiles. Those ports support more than 13 million American jobs. NOAA tools—such as nautical charts, accurate positioning services, and ocean and weather observations—play a key role in ensuring that shipments move swiftly and safely along our marine highways.

One of the nation’s busiest port complexes are the Ports of Los Angeles and Long Beach. Almost half of all the containers that enter the U.S. come through this busy complex. Like other ports in the U.S., as the number and size of cargo vessels, cruise ships, and other commercial vessels increase, so does the risk of accidents. More and more, ships need to navigate and operate in close proximity to the seafloor, narrow channels, bridges or other hazards.

At the Port of Long Beach, the amount of space between the bottom of the ship and the seafloor---known as under keel clearance---is set at a minimum of 11 feet. Usually, this would be sufficient for safe and efficient navigation through the port. However, if an 1,100-foot ship pitches by just one degree, the vessel will dip by 9.6 feet. That 11 feet of clearance can quickly be eliminated by a slight pitch, increasing the risk that the ship will run aground.

In response to the need for under keel clearance information, NOAA and its partners worked in conjunction with the Port of Long Beach to provide data to support developed safe navigation of deep-draft ships into the port. This includes information from high-resolution hydrographic surveys, wave buoys, water levels, and the development of a new nearshore wave prediction system. In turn, the Port of Long Beach worked with an industry expert to present NOAA’s data in real-time. As a result, the mariners piloting the ship and port officials are able to more effectively monitor under keel clearance. This approach has the potential to reduce lightering costs---the cost of removing cargo from the ship before it reaches port to lighten the ship and provide more clearance----by almost $10 million per year.  Based on the results of the pilot, NOAA is now looking at how the approach might be applied at other U.S. ports.