Pool 25: Water level management alternatives and their effects on habitat

The effects of changing levee and water level management
practices on present habitat types and amounts on the Upper
Mississippi River floodplain at Pool 25 were predicted.  The
intent of the study was to investigate a broad range of plans
that would provide coarse resolution information and the tools
needed to study specific plans in the future.  Two conditions
were investigated for levees:  the present levee system and all
levees removed.  Five water level management plans were studied: 
the present plan, two plans that would increase water levels, and
two plans that would decrease water levels.   The levee and water
level management variables resulted in a total of ten unique
management alternatives.  Each was studied at four discharge
regimes for a total of 40 scenarios.  A geographic information
system (GIS) was used to investigate the amounts and types of
habitat that would be affected for each scenario.  Tools
developed for the study were a discharge elevation relation for
the tailwater of Pool 25; estimates of water levels throughout
Pool 25 for each scenario; GIS coverages of water levels,
floodplain elevations, levees, and habitat types; and a technique
to compare alternative scenarios.  All GIS analyses were
performed in a raster environment.