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The National Hydrography Dataset (NHD) is a digital database of surface water features used to make maps. It contains features such as lakes, ponds, streams, rivers, canals, dams, and stream gauges for the United States.
Cartographers can link to or download the NHD to use in their computer mapping software. The NHD is used to represent surface water on maps and is also used to perform geospatial analysis. It is a digital vector geospatial dataset designed for use in geographic information systems (GIS) to analyze the flow of water throughout the nation. The dataset represents over 7.5-million miles of streams/rivers and 6.5-million lake/ponds.
In mapping, the NHD is used with other data themes such as elevation, boundaries, and transportation to produce general reference maps. In geospatial analysis the NHD is used by scientists using GIS technology. This takes advantage of a flow direction network that can be processed to trace the flow of water downstream. A rich set of attributes used to identify the water features includes an identifier, the official name of the feature, the length or area of the feature, and metadata describing the source of the data. The identifier is used in an addressing system to link specific information about the water such as water discharge, water quality, and fish population. Using the basic water features, flow network, linked information, and other characteristics, it is possible to study cause and effect relationships, such as how a source of poor water quality upstream might affect a fish population downstream.
The NHD is part of the United States Geological Survey The National Map for the United States. The NHD is also linked with similar datasets representing the surface water for Canada and Mexico. The dataset primarily maps features a 1:24,000-scale, but in certain areas provides detail at 1:5,000-scale. A version of the NHD called the NHDPlus is integrated with elevation and other landscape data to create detailed drainage catchments and flow volume and velocity estimates for streams and rivers of the U.S. at 1:100,000-scale. This data is available from the United States Environmental Protection Agency.
A geographic information system (GIS) consists of integrated computer hardware and software that store, manage, analyze, edit, output, and visualize geographic data. Much of this often happens within a spatial database; however, this is not essential to meet the definition of a GIS. In a broader sense, one may consider such a system also to include human users and support staff, procedures and workflows, the body of knowledge of relevant concepts and methods, and institutional organizations.
In modern mapping, a topographic map or topographic sheet is a type of map characterized by large-scale detail and quantitative representation of relief features, usually using contour lines, but historically using a variety of methods. Traditional definitions require a topographic map to show both natural and artificial features. A topographic survey is typically based upon a systematic observation and published as a map series, made up of two or more map sheets that combine to form the whole map. A topographic map series uses a common specification that includes the range of cartographic symbols employed, as well as a standard geodetic framework that defines the map projection, coordinate system, ellipsoid and geodetic datum. Official topographic maps also adopt a national grid referencing system.
Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the land forms and features themselves, or a description or depiction in maps.
A GIS file format is a standard for encoding geographical information into a computer file, as a specialized type of file format for use in geographic information systems (GIS) and other geospatial applications. Since the 1970s, dozens of formats have been created based on various data models for various purposes. They have been created by government mapping agencies, GIS software vendors, standards bodies such as the Open Geospatial Consortium, informal user communities, and even individual developers.
The Queets River is a river in the U.S. state of Washington. It is located on the Olympic Peninsula, mostly within the Olympic National Park and empties into the Pacific Ocean.
The Quaboag River is a 25.7-mile-long (41.4 km) river in Massachusetts that heads at Quaboag Pond in Brookfield at an elevation of 594 feet (181 m) above sea level. It flows west to the village of Three Rivers, Massachusetts, at an elevation of 290 feet (88 m).
The Sudbury River is a 32.7-mile-long (52.6 km) tributary of the Concord River in Middlesex County, Massachusetts, in the United States.
Geographic information systems (GISs) have become a useful and important tool in the field of hydrology to study and manage Earth's water resources. Climate change and greater demands on water resources require a more knowledgeable disposition of arguably one of our most vital resources. Because water in its occurrence varies spatially and temporally throughout the hydrologic cycle, its study using GIS is especially practical. Whereas previous GIS systems were mostly static in their geospatial representation of hydrologic features, GIS platforms are becoming increasingly dynamic, narrowing the gap between historical data and current hydrologic reality.
The Burnt River is a 98-mile-long (158 km) tributary of the Snake River in eastern Oregon, United States. It enters the Snake near Huntington at a point upstream of the Powder River and downstream of the Malheur River, slightly more than 327 miles (526 km) from the Snake's confluence with the Columbia River. Draining 1,090 square miles (2,800 km2), it flows predominantly west to east.
The Fish River is a 69.9-mile-long (112.5 km) river in northern Maine in the United States. It is a tributary of the Saint John River, which flows to the Bay of Fundy in New Brunswick, Canada.
The Moose River is an 83-mile-long (134 km) river in Maine. Its source is in Beattie, on the Canada–United States border, which runs along the height of land between the watersheds of the Kennebec River in Maine and the Chaudière River in Quebec. From there, the river runs east through Attean Pond and Wood Pond, past the town of Moose River, then through Long Pond and Brassua Lake. The Moose River empties into Moosehead Lake, the source of the Kennebec River, in Rockwood Strip. The International Railway of Maine was built along Moose River in 1889.
The Sandy River is a 73.3-mile-long (118.0 km) tributary of the Kennebec River in the U.S. state of Maine.
The Sebec River is a tributary of the Piscataquis River in Piscataquis County, Maine. From the outflow of Sebec Lake in Sebec, the river runs 10.0 miles (16.1 km) east and southeast to its confluence with the Piscataquis in Milo.
The Poesten Kill is a 26.2-mile-long (42.2 km) creek in Rensselaer County, Upstate New York. It flows westerly from its source at Dyken Pond, located in the town of Berlin, to its mouth at the Hudson River in the city of Troy. The creek was historically used as a source of water for the local farmers and residents. During the Industrial Revolution, the creek became an important source of water power, and many mills and factories sprung up along its banks.
West Little Owyhee River is a 63.1-mile-long (101.5 km) tributary of the Owyhee River in the U.S. state of Oregon. The source of the river is at an elevation of 6,508 feet (1,984 m) near McDermitt, while the mouth is at an elevation of 4,373 feet (1,333 m) in the Owyhee Desert. West Little Owyhee River has a 310-square-mile (800 km2) watershed.
Rock Creek is a 56-mile (90 km) intermittent stream flowing in Lake and Harney counties in the U.S. state of Oregon. The source of Rock Creek is at an elevation of 6,914 feet (2,107 m) on Hart Mountain, while the mouth is at an elevation of 4,557 feet (1,389 m) in the Catlow Valley. Rock Creek has a 269-square-mile (700 km2) watershed.
Toms Creek is a 20.8-mile-long (33.5 km) tributary of the Monocacy River in Pennsylvania and Maryland in the United States. Via the Monocacy River, it is part of the Potomac River watershed, flowing to Chesapeake Bay and the Atlantic Ocean.
Poso Creek or Posey Creek is an 87.9-mile (141.5 km) intermittent stream in Kern County, California.
Neepaulakating Creek is a 2.4-mile long (3.8 km) tributary of Papakating Creek in Wantage Township in Sussex County, New Jersey in the United States. It is one of three streams feeding the Papakating Creek, a major contributor to the Wallkill River. Although the stream was dammed in the 1950s to create Lake Neepaulin as the focal point of a private residential development, the stream did not receive a name until 2002. Residents chose a name that combined elements of the names "Neepaulin" and "Papakating", and submitted a proposal to the United States Board of Geographic Names. The name was approved in 2004.
Watershed delineation is the process of identifying the boundary of a watershed, also referred to as a catchment, drainage basin, or river basin. It is an important step in many areas of environmental science, engineering, and management, for example to study flooding, aquatic habitat, or water pollution.
Simley, J.D., Carswell Jr., W.J., 2009, The National Map—Hydrography: U.S. Geological Survey Fact Sheet 2009-3054, 4 p.
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