Using multiple sites provides a way to control object interactions within a single drawing. You can move or copy objects into the same site when you want them to interact, and move or copy them into separate sites when you want to isolate them.
The fact that sites are transparent and always visible can be helpful in some situations, such as when you have soil-type parcels overlaid on a grading plan. In other situations, you might want to visibly mark the objects to indicate their site. For example, if you have two phases of a residential project in different sites, you can use the Site Properties dialog box to set the starting parcel number to 101 in one site, and 201 in the other. You can also use different object styles in each site.
When you create alignments, you have the option of not assigning them to a site. Therefore you can keep your alignments from interacting with other site objects during the design period. After the alignment design is finished, you can move the alignments into the parcels’ site and work with the interactions between both object types.
If you use alignments in the design of utility networks, you may want to keep these alignments in a separate site from the parcels and the road alignments. Similarly, you may want to keep your overall grading plan in a separate site from the alignments and parcels.
For more information, see Site Interactions in the Grading chapter.