Upper Midwest Environmental Sciences Center
July 1998 PSR 98-07
Conversion of US Army Corps of Engineers Land Cover Data
by Peter E. Joria
Periodic land cover maps of the Upper Mississippi River System
(UMRS) floodplain are required by resource managers to understand
and monitor the system. Typically, land cover maps for the UMRS
are produced through interpretation of aerial photography and stored
as geographic information system ARC/INFO coverages. True-color
and color-infrared photos (scale = 1:15,000) of the entire UMRS
were collected in 1989 as part of the Long
Term Resource Monitoring Program (LTRMP). Nearly the entire
UMRS floodplain was interpreted from these photos. The exceptions
were Pools 1-3, most of the Open River (the UMRS from Lock &
Dam 26 located near Alton, Illinois downstream to its confluence
with the Ohio River near Cairo, Illinois), and about half of the
Sections of the UMRS have been rephotographed and interpreted in
subsequent years, but the same gaps in coverage remain. In an effort
to fill these gaps, land cover data for the Open River were acquired
by the U.S. Army Corps of Engineers (USACE) to incorporate into
their River Engineering and Environmental Geospatial Information
System (REEGIS, Figure). Recently, a conversion routine was developed
by Environmental Management Technical Center staff to translate
REEGIS data from Intergraph Design files to ARC/INFO coverages.
The 1994 land cover for the St. Louis District was acquired as a single, seamless vector file (fwland94.dgn) and associated attribute data file (fwland94.dmp). The following basic guidelines were used to convert the 1994 land cover layer to an ARC/INFO coverage. These steps may not be exactly the same for all REEGIS conversions. For more information, consult the ARC/INFO on-line help for the commands IGDSINFO and IGDSARC, as well as on-line help under Contents>Data Automation> Data Conversion> Converting IGDS data. The author will provide a more detailed explanation of the conversion, including examples of command usage, upon request.
Basic guidelines for file conversion:
Additional work is required to fully integrate non-program data such as REEGIS with the LTRMP database. Spatial and thematic accuracy standards must be met. To the extent possible, the land cover schemes must be cross-walked so that REEGIS categories can be reclassed into their equivalent LTRMP categories. When this work is completed, the 1994 REEGIS land cover data will be made available to the LTRMP community. With some modification, this routine may also be used to convert other themes within the REEGIS database into a format compatible with LTRMP data.
This report is a product of the Long Term Resource Monitoring Program for the Upper Mississippi River System.
For further information, contact
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