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forecast and place into the data bank selected alternative future development patterns; 3) perform comprehensive assessments of the selected alternative futures by use of the data bank and supporting computer programs; and 4) document the assessment for study by the general public and community officials. Subsequent assessment services would be provided by the Corps on a continuing basis at local agency request. Specific develop- ment proposals would be assessed, land use development policies analyzed and informed technical guidance provided by the Corps to the local officiais. The analytical techniques developed center on integrated use of computerized spatial, gridded geographic and resource data meso Data such as existing and alternative future land use patterns, topographic elevation and slope, soil properties, hydrologic subbasins and environmental habitats are encoded and placed in a permanent computerized grid cell data file. A family of special purpose utility computer programs access the files, select, coordinate and interpret the data for selected variables into specific parameters that are subsequently formatted for input to traditionally used computer modeling programs. The utility and modeling programs perform the comprehensive analysis. A basic concept is to use traditional analysis methods where possible and provide for automation of analysis and displays where appropriate, while providing the capability to perform consistent analysis over a very broad range of detail. For instance, one might wish for a general assessment of an entire urban watershed unit of 20 sq. miles for an al. ternative future land use pattern, and desire to have the analysis with a minimum of prior data preparation, Le., essentially only have available the proposed land use pattern. In a different situation, one might wish a specific assessment of a portion of 3. tributary area of say one sq. mile of the 20 sq, miles where a 300-acre shopping center with attendant SUT- face drainage works such as channel straightening and lining and detention storage are proposed. These extreme levels of detail are accommodated by providing the capability for automated computer analysis that can be interrupted at a number of stages during the computations and more detailed specifically tailored data substituted for the automati- cally generated data. Flood hazard evaluations involve computation of flow rates for event::. of :nterest (e .g., several events ranging from the 5. to 100-year exceedance interval magnitude) for de- signated control points, and the corresponding water surface elevations and flooded area delineation. The modeling programs that perform the analysis are the traditional Corps of Engineers hydrologic engineering programs. The hydrologic modeling program parameters are determined automatically from the computerized data files, The economic damage potenrial is characterized by selected event (such as the 100. year exceedance interval event) damage potential and expected annual damage at desig. nafed control points, The analysis develops elevation damage relationships by automated analysis of land use and topographic data from the grid data file that is subsequently input to a traditional hydrologic engineering computer program rhat performs the damage assessments. The environmental assessment consists of tabulating land use/environmental habitat coincidents, computation of urban stormwater runoff (quantity and quality), land sur. face erosion and in-stream water quality using other Corps of Engineers computer pro- grams. The data and parameters for the analysis are automatically generated from the computerized data files. The methods were applied to a small test area of a larger pilot study (U.S. Army Engineer District, Savannah, 1975) for the purpose of testing, debugging, and concept reo fmement. The pilot study is projected for completion in early 1977. The test area for e < , , e 2 e