The general location of the land/water transition of a controlled feature. Should be noted with the Elevation attribute set and feature level metadata.
The land/water transition as of the date of photography. Orthoimagery used must be noted in the feature level metadata.
The vertical distance from a given datum.
Each NHD Feature Class is broken down by feature type (Ftype) which have a 3-digit coded value and a name.
A Geographic Coordinate System called the North American Datum of 1983. This is the Coordinate system the NHD comes in when you download it.
A closed feature used to channel flowing water to another site
A feature-based database containting surface water features for the United States at a scale of 1:24,000 and higher.
the highest elevation where a waterbody feature and land meet. Normally used when a feature is controlled by a dam and may not match orthoimagery.
A feature-based database containting surface water features for the United States at a scale higher than 1:24,000.
A feature-based database containting surface water features for the United States at a scale of 1:100,000.
A digital vector dataset representing surface water features for the United States.
National Inventory of Dams- the NHD Derives its Dams from this database.
The general location of the land/water transition uncontrolled feature.
National Water Information System. The NHD Derives it's Water Quality Monitoring Stations and Stream Gages from this database.
Scale is the relationship between distance on the map and distance on the ground. For example, if the scale is 1:24,000, 1 map unit would represent 24,000 ground units.
The elevation at which overflow from the feature will exit through the spillway.
Height of water surface.
A dataset containing Hydrologic Units that define drainage areas for suraface water.