Hydrography depicts surface water, including rivers and streams, lakes and ponds, canals, coastlines, and many other water features. The Hydrography layer combines two data sets: the 2014 National Map Hydrographic Geodatabase (1:1,000,000 scale) for small to medium scales, and the 2016 National Hydrography Datataset (NHD) (1:24,000 scale) for large scale mapping. Hydrography is depicted in two layers. Rivers & Streams depicts linear hydrography, including rivers, streams, canals, pipes, and artificial paths (line networks through larger water bodies). Waterbodies depicts area hydrography, including larger rivers, lakes, ponds, seas, bays, estuaries, etc.
National Hydrography Dataset (Flowline)
The National Hydrography Dataset (NHD) is used to portray surface water. The NHD represents the drainage network with features such as rivers, streams, canals, lakes, ponds, coastline, etc. The principal components of the NHD are:
- NHDFlowline: This is the fundamental flow network consisting predominantly of stream/river and artificial path vector features. It represents the spatial geometry, carries the attributes, models the water flow, and contains linear referencing measures for locating events on the network. Additional NHDFlowline features are canal/ditch, pipeline, connector, underground conduit, and coastline.
- NHDArea: This feature class contains many additional features of water polygons. One of the more important is the stream/river feature. It represents the aerial extent of the water in a wide stream/river with a basic set of attributes. They typically contain NHDFlowline artificial paths that are used to model the stream/river. Artificial path carries the critical attributes of the stream/river, whereas NHDArea represents the geometric extent.
- NHDWaterbody: Basic waterbodies such as lake/pond features are represented here. They portray the spatial geometry and the attributes of the feature. These water polygons may contain NHDFlowline artificial paths to allow the representation of water flow. Other NHDWaterbody features are swamp/marsh, reservoir, playa, estuary, and ice mass.
Rural vs. Urban Childhood Poverty
This layer displays information about the difference between rural and urban childhood poverty across the United States. Data are based on census-tract level information from the 2010-14 American Community Survey. Census tracts are defined as urban or rural based on 2010 US Census Bureau definitions; tract level information is then aggregated to and displayed at the Public Use Microdata Area (PUMA) geographic level.
Rural vs. Urban Educational Attainment
This layer displays information about the difference between rural and urban educational attainment across the United States. Data are based on census-tract level information from the 2010-14 American Community Survey. Census tracts are defined as urban or rural based on 2010 US Census Bureau definitions; tract level information is then aggregated to and displayed at the Public Use Microdata Area (PUMA) geographic level.
Adequate Fruit Consumption by State, 2015
Indicator percentages are acquired from analysis of annual survey data from the Behavioral Risk Factor Surveillance System (BRFSS) for survey year 2015. Percentages are generated based on valid responses to the following questions:
“During the past month, not counting juice, how many times per day, week, or month did you eat fruit? Count fresh, frozen, or canned fruit.” and “During the past month, how many times per day, week or month did you drink 100% PURE fruit juices? Do not include fruit-flavored drinks with added sugar or fruit juice you made at home and added sugar to. Only include 100% juice.”
Adequate Vegetable Consumption by State, 2015
Indicator percentages are acquired from analysis of annual survey data from the Behavioral Risk Factor Surveillance System (BRFSS) for survey year 2015. This indicator represents the percentage of adults who indicated that they consumed more than 1 serving of other vegetables per day.
Tax Returns Claiming Earned Income Tax Credits
This layer displays information about tax credits and tax deductions claimed by tax filers. Information is available for all ZIP codes and counties where 10 or more total tax returns were filed. Eligible tax payers may receive between $1 and over $5,000 in Earned Income Tax Credits (EITC).
Statistics of Income from the IRS
Layers display ZIP code and county-level information about tax returns filed in 2013, including the number and percentage of returns with an adjusted gross income less than $20,000. Data is acquired through the Brookings Institute’s Earned Income Tax Credit Interactive.
Per Capita Income, 2014
This layer displays per capita personal income by county. This measure of income is calculated as the total personal income of the residents of an area divided by the population of the area. Per capita personal income is often used as an indicator of consumers’ purchasing power and of the economic well-being of the residents of an area. Information used in this map layer is acquired from the US Bureau of Economic Analysis Regional Economic Accounts: Economic Profile (CA30).
Self Employment, 2014
This layer displays information about proprietor employment (or self employment) and income by county. Average measures of income are calculated as the total proprietor income of an area divided by the estimated number of proprietors within the area. Percentages are calculated by dividing the estimated proprietor employment by the total employment in an area. Information used in this map layer is acquired from the US Bureau of Economic Analysis Regional Economic Accounts: Economic Profile (CA30).