GEOSPATIAL DATA RESOURCES
The
Office of State Planning Coordination provides staff for
the Delaware
Geographic Data Committee (DGDC), which is established
to coordinate the use and sharing of geospatial data in
Delaware (
29 Del. Code, § 9143). Geospatial data sets
combine the detailed information found in a database (the
"what") with the locational information (the "where") of a
map. They are generally used with
Geographic Information System (GIS) software tools
such as ESRI's ArcMAP suite (now widely in use among
Delaware state agencies and county and local governments).
Geospatial data sets are increasingly also used in
browser-based consumer applications such as Google Maps, Yahoo Maps, and Bing Maps and are the
data basis for GPS-based navigation systems.
THE DELAWARE SPATIAL DATA FRAMEWORK
Delaware's geospatial data resources are based on a shared digital base map known as the Delaware Spatial Data Framework, part of a national effort to create a seamless collection of spatial data sets, based on local knowledge, known as the National Spatial Data Infrastructure (NSDI). Delaware Framework data sets are provided by county and state agencies, often in partnership with federal government agencies and are served via the Delaware DataMIL in a browser-based mapping application and as streamed geospatial data that can be accessed using a number of GIS software tools.
Delaware's Framework data sets are organized into eight areas of information: Orthophotography, Transportation, Water Features, Elevation, Governmental Units, Land Parcels, Land Use and Land Cover, and Geographic Names.
Orthophotography
The most recent statewide orthophotography was collected in spring of 2007 in a
project funded jointly by the Delaware Office of Management
and Budget, DNREC, DelDOT, the U.S. Geological Survey
Geospatial Information Office, all three Delaware Counties and the
City of Dover.
Earlier statewide orthophotography projects collected data for 1992, 1997 and 2002. These data sets and the 2007 orthophotography can be viewed on the Delaware DataMIL along with historical aerial photography, dating back as far as 1937, that has been orthorectified by the Delaware Geological Survey. These orthos can be viewed on-line and can be used as an Internet Map Stream (IMS) in GIS and other software packages that can connect to IMS data streams.
Versions of the 1992 and 1997 imagery are also available in a reduced-resolution form for download from the Spatial Analysis Lab of the University of Delaware's College of Agriculture and Natural Resources.
The 2002 and 2007 aerial photography projects are organized using an orthophotography tile index (available as a PDF map or as downloadable spatial data) which divides the state into 2010 1-kilometer by 1-kilometer tiles. Full resolution GeoTIFF tile data is available on a limited basis on the USGS EROS Data Center via the Seamless Data Distribution System and on user-submitted digital media. (Back to the Framework List)
Transportation
The Delaware Department of Transportation (DelDOT)
has contracted with TeleAtlas to maintain basic statewide road data. The public portion of this data is served on the Delaware DataMIL. DelDOT also offers for download a statewide centerline data set. (Back to the Framework List)
Water Features
Delaware uses an extract of the USGS National Hydrography
Dataset (NHD). The Delaware pportion of NHD is available for download (ZIPPED) folder from the USGS. Staff with the Department
of Natural Resources and Environmental Control work
with the USGS and the Delaware
Geological Survey to update and correct this national
data set to state-level accuracy. (Back to the Framework List)
Elevation
Two-foot interval contour data have been developed for all of Delaware from LiDAR data collected in 2005 (Sussex County) and 2007 (Kent and New Castle Counties). (Back to the Framework List)
Governmental Units
Delaware's state and county boundary lines are served on
the Delaware DataMIL along with a Delaware
Outline, in polygon form, which presents a more
familiar view of the state's landward boundaries and
shoreline. (Back to the Framework List)
A statewide data sets of Delaware's Municipal Boundaries is maintained by the Office of State Planning Coordination, based on reviews of Municipal Annexations and local government comprehensive plans. (Back to the Framework List)
Land Parcels
All three Delaware counties maintain land parcel data sets
that include at least parcel polygons and parcel numbers. Parcel data for New Castle and Sussex Counties are available on the Delaware DataMIL. Data for Kent County are available by request from the county. (Back to the Framework List)
Land Use and Land Cover
A
2007 Land Use/Land Cover data set is published by the
Office of Management and Budget. This data was developed as
part of the 2007 orthophotography project. It updates Land
Use/Land Cover data from
2002 (which was an update of
1997 data). Earlier Land Use/Land Cover data is hosted
by the University of Delaware's Spatial Analysis Lab. (Back to the Framework List)
Geographic Names
The Delaware Geological Survey maintains a subset
of the USGS Geographic Names Information System (GNIS) as
a basis for Delaware place names on the Delaware
DataMIL. This is augmented with community names data
from all three Delaware counties and school sites and names provided by the
Delaware Department of Education. (Back to the Framework List)
GEOSPATIAL DATA FROM THE OFFICE OF STATE PLANNING COORDINATION
The Office of State Planning Coordination creates, maintains or serves several other geospatial data sets that are not a part of the Framework.
- State Strategies for Policies and Spending
- PLUS Review data sets showing locations of projects reviewed under the Preliminary Land Use Service (PLUS) process, from 2004 to the present. Earlier land use change reviews were conducted between 1999 and 2004 under the Land Use Planning Act (LUPA).
- The Future Annexation Areas identified in the certified comprehensive plans of Delaware's incorporated towns and cities.
- Completed Municipal Annexations (since 2004) as reviewed by the Office of State Planning Coordination under the Municipal Annexation Plan of Services requirement.
- Impervious Surfaces data derived from the 2007 aerial photography.
- Transportation Analysis Zones (TAZs) used for transportation planning in each of Delaware's Counties.
- Assisted Rental Units mapped by the Delaware State Housing Authority.
