Framework hydrography data include surface water features such as lakes and ponds, streams and rivers, canals, oceans, and shorelines. Each of these features has the attributes of a name and feature identification code. Centerlines and polygons encode the positions of these features.

Features Include: Many hydrography data users need complete information about connectivity of the hydrography network and the direction in which the water flows encoded in the data. To meet these needs, additional elements representing the flow of water and connections between features may be included in framework data; and a shoreline is the intersection of the water's surface with land. It usually is referenced to some analytically determined stage of the tide for coastal water, or other water level for lakes and rivers. Several shorelines, referenced to different stages of the water such as "mean high water" and "mean lower low water," are included in the framework.

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