Grid Modification =================================== This section outlines a process to port data after the domain has been changed or the grid elements size has been changed but a project has many components developed. This scenario occurs when an old project is revisited or a new project is extended to a larger area or clipped to a smaller area. .. note:: The process will be outlined based on the available layers and procedures in the QGIS FLO-2D Plugin order. 1. Computational Domain Layer ------------------------------ - Update polygon to cover complete project extent. - Set cell size. 2. Grid -------- - Create the grid. 3. Interpolate Elevation --------------------------- - Import full coverage raster. - If a new area is needed, it is easy to create a mosaic of the two rasters. - Export the grid layer as a raster and use a mosaic tool to combine the two rasters. - It is a good idea to use the new grid element resolution and alignment as the extent and size for the raster. - Sample full coverage raster with the Sampling grid elevation from raster layer. 4. Roughness -------------- - Recalculate from a full coverage shapefile/raster. - If shapefile is not available, - Export the old grid and intersect it with roughness polygons for the new grid. - Use a Dissolve tool to simplify the shapefile so it combines like polygons with the same n-value. 5. Buildings ------------- - Recalculate from Blocked Areas layer. - It may be necessary to add buildings from additional area. - The open street map downloader can download buildings. See the Building section of the Self Help Training for more info. 6. Extra Grid features ----------------------- - Run separate tools for Spatial Tol, Spatial Froude, Spatial Shallow n, and Gutters. 7. Infiltration ----------------- - Recalculate from external layers. - It may be necessary to add infiltration areas to the infiltration shapefile. - If extra data is needed, intersect the new data into the Soil and Landuse shapefiles. 8. Hydraulic Structures ------------------------- - Copy polyline features from Structures Schematic Layer. - Paste into Structures User Layer. - Run structures schematize tool to refresh data. - Add new structures using the editor tool and table editor after refreshing the data. - Rerun schematize tool to add new data to final Schematic Layer. 9. Levees ---------- - If User Layers Levee Lines are available, use them to recalculate the levees. - If Levee Lines User Layer is not present, use this simple process to copy them from the Schematized Levees. - Create levee lines the center of the levee. This is just the standard create levee polyline using the editor add polyline process. - Make certain these lines cross the Schematic Levees frequently. - Intersect the Levee Lines Layer and Levees Layer to generate a point file with crest elevation. - Copy that to the Elevation Points Layer. - Run the Levee Calc tool with Levee Lines and Points. - The idea is to intersect the schema lines and get the crest elevation for the points layer. .. note:: This does not work for walls. - Walls - Recalculate walls from wall data. 10. Boundary Conditions ----------------------- - Run schematize button. - The downstream boundary might need to be edited or repositioned. 11. Rain -------- - Rerun depth Area Reduction sampler if used. - Save and export data. 12. Channels ------------- - Rerun schematize. - Export .DAT files. - Run Interpolator. - Import interpolated channels. - It may be necessary to make left and right bank alignment corrections. 13. Floodplain cross sections ------------------------------ - Rerun schematize. - It may be necessary to add new cross sections. Storm Drain ------------ - Add new data to the storm drain shapefiles. - Rerun storm drain calculator tool to convert to the FLO-2D User layers. - Run schematize. - Export swmm.inp. FLO-2D Pro ----------- - Export Data - Run Model - It is probably wise to export the data and test run at more convenient points along this outline.