Marine Information Overlay (MIO) is a generic term used to describe chart and navigation related information that supplement the content that is already contained in an ENC. This includes both static and dynamic information such as tide/water level, current flow, meteorological, oceanographic, and environmental protection. With the advent of S-100 and S-101, there is increased interest in providing a wide variety of ‘new’ overlay information. This paper provides a brief history of S-57 MIOs. Examples of navigational and non-navigation MIOs are given in terms of how currently used, by who, and for what purpose. Recommendations are provided for making a transition from S-57 MIOs to S-100 overlays that can be used with the ‘Next Generation’ ENC. More specifically, what has been proposed, how should they work, who will provide, and some future challenges/opportunities related to implementation.


Center for Coastal and Ocean Mapping

Publication Date


Journal Title

U.S. Hydrographic Conference

Conference Date

March 16-19, 2015

Publisher Place

National Harbor, Maryland, USA


International Hydrographic Organization

Document Type

Conference Proceeding