{
 "culture": "en-US",
 "name": "NHD_Flowlines",
 "guid": "E0B5D616-A9EF-4D53-AFA5-FE2B57113AEC",
 "catalogPath": "",
 "snippet": "This dataset comprises National Hydrology Dataset (NHD) flowline data for the two HU6 (hydrographic units level 6) that intersect San Diego County (i.e. Laguna-San Diego Coastal and Salton Sea units).\n\nNHDFlowlines consist of routes that make up a linear surface water drainage network. Flowlines have a reach code and a measure, allowing for the establishment of upstream/downstream relationships. This network allows for powerful analysis and modeling capabilities.\n\nThe NHD is a national framework for assigning reach addresses to water-related entities, such as industrial discharges, drinking water supplies, fish habitat areas, wild and scenic rivers. Reach addresses establish the locations of these entities relative to one another within the NHD surface water drainage network, much like addresses on streets. Once linked to the NHD by their reach addresses, the upstream/downstream relationships of these water-related entities--and any associated information about them--can be analyzed using software tools ranging from spreadsheets to geographic information systems (GIS). GIS can also be used to combine NHD-based network analysis with other data layers, such as soils, land use and population, to help understand and display their respective effects upon one another. Furthermore, because the NHD provides a nationally consistent framework for addressing and analysis, water-related information linked to reach addresses by one organization (national, state, local) can be shared with other organizations and easily integrated into many different types of applications to the benefit of all.",
 "description": "This dataset comprises National Hydrology Dataset (NHD) flowline data for the two HU6 (hydrographic units level 6) that intersect San Diego County (i.e. Laguna-San Diego Coastal and Salton Sea units). NHD data was downloaded in FGDB format for HU-4 (SubRegion) for NHD_H_1810_HU4 and NHD_H1807_HU4 from https://apps.nationalmap.gov/downloader/  Features from NHDFlowline feature class from NHD_H_1810_HU4 and NHD_H1807_HU4 were selected that intersect the two HU6 units and were projected to NAD83 State Plane Coordinate System.NHDFlowlines consist of routes that make up a linear surface water drainage network. Flowlines have a reach code and a measure, allowing for the establishment of upstream/downstream relationships. This network allows for powerful analysis and modeling capabilities.The National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution NHD, generally developed at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. (Data for Alaska, Puerto Rico and the Virgin Islands was developed at high-resolution, not 1:100,000 scale.) Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes, the Atlantic and Pacific Oceans and the Gulf of Mexico. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee.Statements of horizontal positional accuracy are based on accuracy statements made for U.S. Geological Survey topographic quadrangle maps. These maps were compiled to meet National Map Accuracy Standards. For horizontal accuracy, this standard is met if at least 90 percent of points tested are within 0.02 inch (at map scale) of the true position. Additional offsets to positions may have been introduced where feature density is high to improve the legibility of map symbols. In addition, the digitizing of maps is estimated to contain a horizontal positional error of less than or equal to 0.003 inch standard error (at map scale) in the two component directions relative to the source maps. Visual comparison between the map graphic (including digital scans of the graphic) and plots or digital displays of points, lines, and areas, is used as control to assess the positional accuracy of digital data. Digital map elements along the adjoining edges of data sets are aligned if they are within a 0.02 inch tolerance (at map scale). Features with like dimensionality (for example, features that all are delineated with lines), with or without like characteristics, that are within the tolerance are aligned by moving the features equally to a common point. Features outside the tolerance are not moved; instead, a feature of type connector is added to join the features. This statement is generally true for the most common sources of NHD data. Other sources and methods may have been used to create or update NHD data. In some cases, additional information may be found in the NHDMetadata table.",
 "summary": "This dataset comprises National Hydrology Dataset (NHD) flowline data for the two HU6 (hydrographic units level 6) that intersect San Diego County (i.e. Laguna-San Diego Coastal and Salton Sea units).\n\nNHDFlowlines consist of routes that make up a linear surface water drainage network. Flowlines have a reach code and a measure, allowing for the establishment of upstream/downstream relationships. This network allows for powerful analysis and modeling capabilities.\n\nThe NHD is a national framework for assigning reach addresses to water-related entities, such as industrial discharges, drinking water supplies, fish habitat areas, wild and scenic rivers. Reach addresses establish the locations of these entities relative to one another within the NHD surface water drainage network, much like addresses on streets. Once linked to the NHD by their reach addresses, the upstream/downstream relationships of these water-related entities--and any associated information about them--can be analyzed using software tools ranging from spreadsheets to geographic information systems (GIS). GIS can also be used to combine NHD-based network analysis with other data layers, such as soils, land use and population, to help understand and display their respective effects upon one another. Furthermore, because the NHD provides a nationally consistent framework for addressing and analysis, water-related information linked to reach addresses by one organization (national, state, local) can be shared with other organizations and easily integrated into many different types of applications to the benefit of all.",
 "title": "NHD_Flowlines",
 "tags": [
  "FWHYDROGRAPHY",
  "Hydrography",
  "Stream / River",
  "Lake / Pond",
  "Canal / Ditch",
  "Reservoir",
  "Spring / Seep",
  "Swamp / Marsh",
  "Artificial Path",
  "Reach Code"
 ],
 "type": "Feature Service",
 "typeKeywords": [
  "ArcGIS",
  "ArcGIS Server",
  "Data",
  "Feature Access",
  "Feature Service",
  "providerSDS",
  "Service"
 ],
 "thumbnail": "thumbnail/thumbnail.png",
 "url": "",
 "extent": [
  [
   -117.838871899179,
   32.1304412113075
  ],
  [
   -114.692044001949,
   34.1674921356498
  ]
 ],
 "minScale": 0,
 "maxScale": 1.7976931348623157E308,
 "spatialReference": "NAD_1983_StatePlane_California_VI_FIPS_0406_Feet",
 "accessInformation": "U.S. Geological Survey in cooperation with SanGIS, U.S. Protection Agency, State Cooperators, U.S. Forest Service, National Geospatial Technical Operations Center and INEGI for data within Mexico.",
 "licenseInfo": ""
}