America's ports are our lifelines for maritime commerce and the national economy. Inadequate or outdated navigational information would pose unacceptable risks to life, property, and coastal environments. To produce accurate charts for safe travels - for commercial and recreational vessels alike - the Office of Coast Survey conducts hydrographic surveys to measure water depths and locate elements that affect navigation. NOS also provides environmental observations and forecasts through programs such as the Physical Oceanographic Real-Time System to help mariners safely navigate in to port.