------Using GIS-Fundamentals of GIS
Lecture 17:
Public Data II: Other Data Sources
Lecture notes by Austin Troy, University of Vermont © 2008
Fundamentals of GIS
National Hydrography Dataset (NHD)
• Comes from both the USGS and the EPA
• Surface water features: lakes, ponds, streams, rivers,
springs
• Nationally consistent
• Order of linkages coded to allow for flow path
analysis
• Background info at http://nhd.usgs.gov/
• Resolutions from 1:100k to 1:24k
©2009 Austin Troy
Fundamentals of GIS
NHD
• Many analysis tools designed for this data.
• For instance: can find the path upstream or downstream
from any point using NHD data and network analyst;
flow reaches are numbered sequentially in order of flow
to allow path analysis
• Stream reaches encoded like addresses on a street
• Connections encoded using topology
• Download data
– http://viewer.nationalmap.gov/viewer/nhd.html?p=nhd
• Other tools available at http://nhd.usgs.gov/tools.html
Lecture notes by Austin Troy & Brian Voigt, University of Vermont © 2011
Fundamentals of GIS
NHD Data Viewer
©2009 Austin Troy
Lecture notes by Austin Troy & Brian Voigt, University of Vermont © 2011
Fundamentals of GIS
NHD
• Contents of
Geodatabase: many
feature classes with
different purposes
• Many will often be
empty
©2009 Austin Troy
Fundamentals of GIS
USDA Data
• USDA houses a
number of data
layers at their new
Geospatial data
gateway
• http://datagateway.
nrcs.usda.gov/
©2009 Austin Troy
Fundamentals of GIS
USDA Gateway Includes
• CLU farm boundaries (not any longer, but Spatial
Analysis Lab has it for VT)
• Hydrologic Units (8 and 12 digit)
• NED elevation
• Digital Raster Graphics (DRG)
• High resolution color orthophotos from 2003, 2004,
2006 (National Agricultural Imagery Program)
• Geographic Names
• Cropland data layer (for some areas)
• NRCS Soils data and soils tables
• Climate Data (precipitation and temperature)
©2009 Austin Troy
Fundamentals of GIS
USDA Gateway Includes
Click for info
and metadata
©2009 Austin Troy
Fundamentals of GIS
• Can Define data extent by county,
state, arbitrary rectangle, or
custom AOI
©2009 Austin Troy
Fundamentals of GIS
Common Land Units (CLU)
• Farm field boundaries
representing smallest
contiguous unit of
cultivated land
• For farms in USDA
programs
• Much more accurate than
“agriculture” category in
NLCD land cover
• Type of crop is unknown
©2009 Austin Troy
Fundamentals of GIS
NAIP
• National Agricultural
Imagery Program
• Digital Imagery,
mosaiced by county,
used by the NRCS and
FSA to look at
compliance with
subsidy programs
• Ortho-rectified
• Color, 1:40,000 scale
• 2003, 2004, 2006, 2008,
2009
©2009 Austin Troy
Fundamentals of GIS
SSURGO Soils Data
• SSURGO: Soil Survey Geographic Data from
NRCS
• Soils data also at
http://soildatamart.nrcs.usda.gov/
• Metadata and standards available at
http://soildatamart.nrcs.usda.gov/SSURGOM
etadata.aspx
• Entails both a polygon layer showing soils
area boundaries, but also an Access Database
of numerous soil attributes
©2009 Austin Troy
Fundamentals of GIS
•
SSURGO
Soil Data Mart interface
• Access—sample tables; there are dozens
©2009 Austin Troy
Fundamentals of GIS
USDA Forest Service Data Gateway
• For each
National Forest
includes layers
like:
boundaries,
trails, roads,
ranges for
certain tree and
animal species,
and ecological
regions
http://fsgeodata.fs.fed.us/vector/index.html
©2009 Austin Troy
Fundamentals of GIS
National Wetlands Inventory (NWI)
• From U. S. Fish and Wildlife Service
• Maps all class 1 and 2 major wetlands
• Available digitally for much of the
country
• 1:24,000 or smaller
• Involves a complex taxonomy of wetlands
codes available at
http://www.fws.gov/wetlands/Data/Wetla
ndCodes.html
• Includes marine, estuarine, riverine,
lacustrine and palustrine types
©2009 Austin Troy
Fundamentals of GIS
©2009 Austin Troy
Fundamentals of GIS
NWI
• Wetlands map interface at http://www.fws.gov/wetlands/Data/Mapper.html
• Allows you to view availability status and to view/download data
©2009 Austin Troy
Fundamentals of GIS
•
NWI
Can make PDFs easily
©2009 Austin Troy
Fundamentals of GIS
NWI
• NWI by wetland type overlaid on NHD streams layer
©2009 Austin Troy
Fundamentals of GIS
TIGER
Topologically Integrated Geographic Encoding and Reference
System
Automates the mapping and related geographic activities required to
support the decennial census and sample survey programs of the
census bureau starting with the 1990 decennial census.
The Census TIGER® system supports:
Creation and maintenance of the digital geographic data base that
includes complete coverage of the United States and its territories
©2009 Austin Troy
Fundamentals of GIS
The TIGER system provides support for:
• Creation and maintenance of a nation wide digital
geographic data base
• Production of maps from the TIGER® data base for all
Census Bureau enumeration and publication programs
• Allows for address geocoding
• Can be integrated with Census attribute databases easily
©2009 Austin Troy
Fundamentals of GIS
TIGER
Accuracy and Attribution:
• TIGER has good attribution, but poor accuracy
•They are based partially on 1:100,000 DLG
• Are often conflated
• This is often used to assign the attributes from TIGER® data
to 1:24,000 DLG data
©2009 Austin Troy
Fundamentals of GIS
The TIGER files contain data describing three feature types:
• Line Features
1. Roads
2. Railroads
3. Hydrography
4. Transportation and Utility Lines
• Boundary Features
1. Statistical boundaries, such as census tracts and blocks
2. Local government boundaries, such as places and counties
3. Administrative boundaries, such as congressional and school districts
• Landmark Features
1. Point landmarks, such as schools and churches
2. Area landmarks, such as parks and cemeteries
3. Key geographic locations, such as apartment buildings and factories
©2009 Austin Troy
Fundamentals of GIS
TIGER line files and the demographic files
Direct linkage using keys built up from:
State FIPS code
County FIPS code
Tract number
Block group number
Block number
©2009 Austin Troy
Fundamentals of GIS
For geographic files
• ESRI:
http://www.esri.com/data/download/census2000_tigerline/index.html
Download 2000 U.S. Census TIGER lines files and
demographic data
• UC Berkeley Tiger Server:
http://sunsite.Berkeley.EDU/GovData/info/tiger.html
For attributes to 2000 and 1990 Census
http://factfinder.census.gov
For data in intermediate years via the American Community
Survey
http://www.census.gov/acs/www/
©2009 Austin Troy
Fundamentals of GIS
TIGER Files & Census Data
• For geographic files
• US Census:
• http://www.census.gov/geo/www/tiger/tgrshp2010/tgrshp2010.
html
• ESRI:
• http://www.esri.com/data/download/census2000_tigerline/inde
x.html
• Download 2000 U.S. Census TIGER lines files and
demographic data
• For Census data
• Decennial Census (2010, 2000,….) and intermediate year
surveys (American Community Survey)
• http://factfinder2.census.gov/faces/nav/jsf/pages/index.xhtml
Lecture notes by Austin Troy & Brian Voigt, University of Vermont © 2011
Fundamentals of GIS
©2009 Austin Troy
Fundamentals of GIS
Fundamentals of GIS
VCGI
• State-level data
– http://www.vcgi.org/
• Includes special access page for Irene-related data
– http://www.vcgi.org/Irene/
Lecture notes by Austin Troy & Brian Voigt, University of Vermont © 2011
Fundamentals of GIS
©2009 Austin Troy
Fundamentals of GIS
• Includes an interactive map browser for “clipping and
zipping” data
Lecture notes by Austin Troy & Brian Voigt, University of Vermont © 2011
Fundamentals of GIS
For continuing data updates, check the data links page at
http://www.uvm.edu/envnr/gradgis/supplement.html
Here you’ll find links to many state level GIS online data
repositories plus many of the ones mentioned here
Another link is to map a network drive to \\zoofiles\gisdata
where you’ll find: NAIP imagery, ortho photos, all VCGI data
plus VTrans database, World data from ESRI, DRG topo maps,
Street maps USA
©2009 Austin Troy
Fundamentals of GIS
Other sources for USGS data
• www.mapmart.com
– Allows users to choose tiles and layers with a geographic
interface
– Most public data are free, but many others available for a
price
– Gives status maps
– Can also buy bulk public data for a fee
• data.geocomm.com
– Not as user friendly
– Just a plain old interface that is hard to navigate
– However, many free data layers and lots of scripts and extensions
©2009 Austin Troy