The Process of Updating Paper Charts
Despite much advancement in navigational technology, the U.S. Coast Guard and NOAA continue to stress the importance of having accurate paper charts on board. Problems such as electronic failure or other complications can and do occur, often at the most inopportune time. When the unexpected happens, NOAA paper charts—long considered the standard—can serve as important insurance. Yet charts have to be accurate to provide value, and they soon become outdated. Unfortunately, many mariners do not fully understand how to keep their charts up-to-date. NOAA works diligently to keep its charts current. Corrections come from three main sources:
Source 1: NOAA performs surveys in oceans, bays, lakes and rivers to monitor changes to depth and shoreline and to locate and disprove Dangers to Navigation (i.e., wrecks, rocks and obstructions). NOAA also receives the latest channel surveys from the Army Corps of Engineers and the latest bridge information from the Coast Guard. And, some United States Power Squadrons collect on-water observations through their Adopt-a-Chart program and submit them to NOAA.
Source 2: Notice to Mariners. Each week, the National Geospatial-Intelligence Agency (NGA) issues what’s called the Notice to Mariners. They contain important information that should be added to existing charts manually, thus bringing them up-to-date. Commercial mariners are fully aware of the Notice to Mariners because by law they are required to carry fully up-to-date NOAA navigational charts at all times.
Source 3: Local Notice to Mariners. The nine district U.S. Coast Guard offices issue the Local Notice to Mariners (LNMs) each week. LNMs provide marine safety information that keeps boaters informed about recent changes—such as a relocated navigation aid or a new obstruction or wreck. Both types of notices are intended to let boaters know it’s time to either manually update their existing paper chart or purchase an updated print-on-demand chart. Unfortunately, many recreational mariners fail to recognize the importance of these changes.