HIFLD OPEN Notice Marks (USACE IENC)

The USACE IENCs coverage area consists of 7,260 miles across 21 rivers primarily located in the Central United States. IENCs apply to inland waterways that are maintained for navigation by USACE for shallow-draft vessels (e.g., maintained at a depth of 9-14 feet, dependent upon the waterway project authorization). Generally, IENCs are produced for those commercially navigable waterways which the National Oceanic and Atmospheric Administration (NOAA) does not produce Electronic Navigational Charts (ENCs). However, Special Purpose IENCs may be produced in agreement with NOAA.

美国陆军工程兵团（United States Army Corps of Engineers, USACE）内河电子航海图（Inland Electronic Navigational Charts, IENCs）的覆盖范围涵盖美国中部地区的21条河流，总长度达7260英里。IENCs适用于由USACE维护、供浅吃水船舶航行的内陆航道，例如航道维护水深为9至14英尺，具体依航道项目授权要求而定。通常情况下，IENCs的制作针对美国国家海洋和大气管理局（National Oceanic and Atmospheric Administration, NOAA）未生产电子航海图（Electronic Navigational Charts, ENCs）的商业通航航道。不过，特殊用途的IENCs可在与NOAA达成协议后进行制作。