Ships must maneuver through a complex system of waterways and channels to reach a U.S. port. Mariners need access to accurate and complete NOS navigational products to maintain safe shipping operations.

The United States has always depended heavily on the nation’s waterways to transport goods, services and people. Since 1807, when Thomas Jefferson created the Survey of the Coast to ensure federal responsibility for accurate navigational services, the nation’s expansive marine transportation system (MTS) has worked to accommodate an ever-growing population and economy.

No single agency has complete responsibility for maintaining the MTS. As the nation’s nautical chartmaker, however, NOAA’s National Ocean Service (NOS) plays a pivotal role in the management and modernization of the nation’s MTS. Many other agencies, including the U.S. Coast Guard (USCG), the U.S. Maritime Administration, the U.S. Army Corps of Engineers, and the U.S. Environmental Protection Agency, work with NOS to cooperatively manage and maintain this critical transportation system.

MTS: An Integral System

The MTS affects virtually everyone and works on national, regional and local levels. The vast system of waterways, ports and land connections is used to move both people and goods to and from the water. In fact, 95 percent of U.S. foreign trade is conveyed via the MTS. Specifically, the system consists of:

• 25,000 miles of navigable channels;
• 300 ports, and more than 3,700 terminals;
• a 1,000 harbor channels; and
• 152,000 miles of rail, 460,000 miles of pipelines and 45,000 miles of interstate highways that connect the waterborne portions of the MTS.

Each year, more than 2 billion tons of freight move along the MTS. The system also contributes more than $742 billion to the U.S. gross domestic product and provides more than 13 million jobs. In addition, more than 134 million ferry passengers and 5 million cruise passengers are transported within the MTS. The system also transfers more than 3.3 billion barrels of oil and petroleum products, supports 110,000 commercial fishing vessels, and accommodates 78 million recreational boaters.

Ships like this one carry more cargo along the nation's MTS than ever before. Marine cargo that moves along the MTS is expected to double within the next generation.

NOS’s Critical Role

As the national authority on nautical charts, tidal and water level information, and accurate maps of the shoreline, NOS provides many tools and services to ensure smooth operations within the MTS. Many NOS tools also work in concert to improve the performances of each. Specific tools and services include:

Nautical charts: Mariners rely on nautical charts to avoid collisions and hidden obstructions at sea, especially when weather conditions, such as fog, storms, and low-visibility days, make navigation difficult. NOS’s Office of Coast Survey (OCS) holds more than 20,000 historical nautical charts and continually updates its collection of 1,000 current charts.

NOS's Office of Coast Survey holds a collection of 20,000 historical nautical charts, including these of the Chicago area in 1911, 1922 and 1926.

Electronic Navigation Charts (ENCs): To improve on traditional nautical charts, OCS now develops ENCs. The ENC is a “smart chart.” It provides the necessary nautical data in addition to vector chart features and hydrographic data, and can be downloaded in electronic format. ENCs also can be integrated with global positioning system (GPS) data—which tells a mariner his or her precise latitude and longitude—and other information like water levels and wind data. Automation and integration of the tools vital to mariners will help to reduce human error even further.

Hydrographic Surveys: NOS scientists employ multi-beam and side-scan sonar systems to precisely determine water depths and underwater obstacles, like wrecks, rocks and seabed changes resulting from earthquakes, storms, dredging operations and natural movement of sediments. The data that are collected during these surveys are especially useful when creating ENCs.

Physical Oceanographic Real-Time System (PORTS): NOS’s PORTS® is a network of stations that records real-time water levels and oceanographic and meteorological data. This information helps mariners know exact water depths at certain times. This allows them to time their entries into and exits from a port while maintaining an appropriate underkeel clearance.

Shoreline Maps: The coastal areas often shift and change because of natural and human-caused disturbances. Remote sensing technologies, aerial photographs and the GPS data that NOS’s National Geodetic Survey collects are used to accurately map the coast and record its changes over time. Shoreline maps also are used as baseline data for developing traditional nautical charts and ENCs.

Hazardous Materials Response and Risk Assessment Tools: NOS’s Office of Response and Restoration (ORR) helps coastal emergency planners prepare for potential hazardous materials spills by developing tools such as trajectory forecasts, atmospheric dispersion models, and chemical threat analyses. ORR scientists also work with the USCG and other authorities to maintain spill preparedness plans in major seaports.

The Future of MTS

The Interagency Committee on the Marine Transportation System was founded to address the system's aging infrastructure and reduce the likelihood of shipwrecks like this one.

Despite the efforts of NOS and its partners to provide the necessary support to the MTS, many ports are already operating at or near capacity. And as global commerce expands, the volume of marine trade will grow—even double—within the next generation, according to NOS and its partner agencies. In addition, the shipping industry is using larger vessels, further straining the limited capabilities of ports.

NOS and its partner agencies have begun to address the aging infrastructure of the MTS. In 1998, they created the Interagency Committee on the Marine Transportation System to coordinate federal activities.

Shortly after, an advisory committee made up of private and nongovernmental parties was formed to raise awareness of the need to modernize the system’s infrastructure, and an advisory council of industry partners was formed as well. NOS and its partners are working to identify the most pressing MTS issues and determine how to improve the nation’s most important transportation infrastructure.