This layer displays the locations of regulated facilities that discharge pollutants into surface waters in the United States. Location and environmental characteristics about facilities requiring discharge permits is contained in the Environmental Protection Agency (EPA) National Pollutant Discharge Elimination System (NPDES). Facilities requiring permits include industrial, municipal, and other facilities must obtain permits if their discharges go directly to surface waters (via discrete conveyances such as pipes or man-made ditches). Individual homes that are connected to a municipal system are not reported to the EPA. For more information, please visit the EPA National Pollutant Discharge Elimination System web page.
Natural Gas Pipelines
The U.S. natural gas pipeline network is a highly integrated network that moves natural gas throughout the continental United States. The pipeline network has about 3 million miles of mainline and other pipelines that link natural gas production areas and storage facilities with consumers. In 2017, this natural gas transportation network delivered about 25 trillion cubic feet (Tcf) of natural gas to 75 million customers.
About half of the existing mainline natural gas transmission network and a large portion of the local distribution network were installed in the 1950s and 1960s because consumer demand for natural gas more than doubled following World War II. The distribution network has continued to expand to provide natural gas service to new commercial facilities and housing developments.
Statistics of U.S. Businesses
These data include number of establishments and corresponding employment change for births, deaths, expansions, and contractions from 2015 to 2016. The data are presented by geographic area, industry, and enterprise employment size.
Oil and Natural Gas Fields
The layer represents Oil and Natural Gas Fields. Generally, Oil and Natural Gas “Fields” are defined as “a low in the Earth’s crust of tectonic origin in which sediments have accumulated.” This definition was originally defined by the Bureau of Land Management (BLM). Within the larger area of the basins this feature class also contains smaller geographic “plays” which are defined as “A set of known or postulated oil and gas accumulations sharing similar geologic, geographic, and temporal properties, such as source rock, migration, pathway, timing, trapping mechanism, and hydrocarbon type. A play differs from a basin; a basin can include one or more plays.” This definition was originally defined by the United States Geologic Survey (USGS) and was appropriated for use in the creation of this feature class. The geographic coverage of this layer is the Continental United States, Canada, and Mexico.
Medical Debt in Collections, 2018
This layer displays debt information at the state and county levels from the Urban Institute’s 2019 Debt in America interactive platform. Data includes medical debt, student loan debt, automobile debt, retail debt and any debt in collections based on December 2018 credit bureau records.
Electric Bulk Power Transmission Lines
This layer represents electric power transmission lines. Transmission Lines are the system of structures, wires, insulators and associated hardware that carry electric energy from one point to another in an electric power system. Lines are operated at relatively high voltages varying from 69 kV up to 765 kV, and are capable of transmitting large quantities of electricity over long distances. Underground transmission lines are included where sources were available.
FBI Crime Statistics
These layers display various violent crime and property crime rates and totals in counties across the United States. Violent crime includes murder, rape, robbery, and aggravated assault while property crimes include burglary, larceny-theft, motor vehicle theft, and arson. Crime totals and rates are multi-year estimates for the three year period 2015-2017. County-level UCR files are based on agency records in a file obtained from the FBI that also provides aggregated county totals. NACJD inputs missing data and then aggregates the data to the county-level.
Army Corps Floodwalls
This layer displays United States Army Core of Engineers surveyed Floodwalls. The USACE defines an Floodwall as a structure erected to protect areas from high river stages. For more information about USACE data, visit the National Levee Database.
Ecoegions
Ecoregions are identified by analyzing the patterns and composition of biotic and abiotic phenomena that affect or reflect differences in ecosystem quality and integrity (Omernik 1987, 1995). These phenomena include geology, landforms, soils, vegetation, climate, land use, wildlife, and hydrology. The relative importance of each characteristic varies from one ecological region to another regardless of the hierarchical level. A Roman numeral classification scheme has been adopted for different hierarchical levels of ecoregions, ranging from general regions to more detailed:
Level I – 12 ecoregions in the continental U.S.
Level II – 25 ecoregions in the continental U.S.
Level III -105 ecoregions in the continental U.S.
Level IV – 967 ecoregions in the conterminous U.S.
Explanations of the methods used to define these multi-agency ecoregions are given in Omernik and Griffith (2014), Omernik (1995, 2004), and CEC (1997).
Watershed Boundary Dataset, 4-Digit Hydrologic Units
The 4-Digit Hydrologic Units, a component of the Watershed Boundary Dataset (WBD), depict the second level hydrologic subdivision of the United States. A 4-digit hydrologic unit includes the area drained by a river system, a reach of a river and its tributaries in that reach, a closed basin(s), or a group of streams forming a coastal drainage area. There are 240 4-digit hydrologic units with an average size of 17,521 square miles (45,378 sq. km.).