ArcGIS REST Services Directory Login
JSON

ItemInfo

Item Information

snippet: This National Hydrography Dataset (NHD) was downloaded from the United States Geological Survey site in July 2012.
summary: This National Hydrography Dataset (NHD) was downloaded from the United States Geological Survey site in July 2012.
extent: [[-124.724423916843,32.5101683864089],[-109.770558206721,49.0393714051311]]
accessInformation: USGS
thumbnail: thumbnail/thumbnail.png
typeKeywords: ["Data","Service","Map Service","ArcGIS Server"]
description: The West Coast Region leverages the National Hydrography Dataset as a base dataset for managing marine and anadromous species. The NHD will be updated over time by downloading new versions from the USGS and publishing it as a new base dataset. The symbology within this map service is broken down by stream order. Stream order (calculated in the NHD using Strahler Stream Order (Strahler, A.N., 1952; Horton, R.E., 1945)) in hydrography deals with the hierarchy of streams from the source (or headwaters) downstream. The headwaters are the first order and downstream segments are defined at confluences (two streams running into each other). At a confluence, if the two streams are not the same order then the highest numbered order is maintained on the downstream segment. At a confluence of two streams with the same order, the downstream segment gets the next highest numbered order. Divergences such as braided streams actually maintain the same order all the way through the braid, just like it was a single stream; however, divergences that are not braided streams keep the upstream order number and follow the normal hierarchy further downstream. Horton, R. E. (1945), "Erosional development of streams and their drainage basins: hydro-physical approach to quantitative morphology", Geological Society of America Bulletin 56 (3): 275–370. Strahler, A. N. (1952), "Hypsometric (area-altitude) analysis of erosional topology", Geological Society of America Bulletin 63 (11): 1117–1142. https://usgs-mrs.cr.usgs.gov/NHDHelp/WebHelp/NHD_Help/Introduction_to_the_NHD/Feature_Attribution/Stream_Order.htm
licenseInfo:
catalogPath:
title: NHD2012
type: Map Service
url:
tags: ["National Hydrograhpy Dataset","NHD","rivers","streams","creeks","flowline","waterbody","stream order","Strahler"]
culture: en-US
name: NHD2012
guid: 1B59BA68-161C-46DF-9E47-E9B1A0BB6205
spatialReference: GCS_North_American_1983