You may display GIS layers as overlays or backgrounds on your WEAP Schematic. These background maps are listed on the left side of the Schematic View, below the legend. The checkbox next to each layer can be used to hide or show it on the schematic. To hide all maps at once, right click on the list of background layers and choose Hide All Layers from the popup menu. Choose Show All Layers to turn them all on. To add a layer, right click on the list of background layers to open the background layers menu and choose Add Vector Layer (e.g. ESRI Shape files: *.shp) or Add Raster Layer (e.g. ArcGIS GRID, GeoTIFF, spatially referenced JPG or GIF, Band Interleaved by Line (BIL), or Band Interleaved by Pixel (BIP)), or choose these options from the Schematic menu at the top. For vector layers, you have much flexibility in choosing map colors, data, styles and labels for display, which can be very helpful in highlighting various features from the layers. These options are available when you first add a vector layer, or when you edit an existing vector layer (double click the layer name to edit). See Map Layer Window for more information. The background layers menu also allows you to remove, set labels or reorder the background maps. A new, blank WEAP area comes preloaded with several global background layers: Major Rivers, Cities, States, Countries and Oceans. You can remove them if you want, but your Schematic must have at least one background layer (either a preloaded layer or one of your own). All background layers must use the same geographic projection. If you add a layer and it does not appear on the Schematic, it may be because it does not use the same projection as the existing background layers. WEAP’s preloaded global layers use the WGS84 projection (WGS84 files are sometimes referred to as ‘unprojected,’ because they are based directly on latitude and longitude.) If you want to add layers that use a projection different from WGS84, here is what you should do. (Note: you must do this BEFORE you add any WEAP objects, such as rivers or demand sites, because when you add them they will use the projection in effect, and will disappear when you change to using a different projection.) Add one of your layers. Remove all layers (such as the preloaded layers) that are in a different projection. Go to Set Area Boundaries and set the boundary using your new layer. If your layer is visible in the Schematic then you have done it correctly. Source.