An "area" in WEAP is defined as a self-contained set of data and assumptions. Its geographical extent is typically a river basin. The data is separated into Current Accounts and any number of alternative scenarios. An area is sometimes referred to as a "data set." All the files for an area are kept together in a directory underneath the WEAP Data Directory.
A study area can be a set of demand sites defined by political or geographic boundaries. It can also be defined as a specific water supply system such as a river basin or a groundwater aquifer. In one case, the point of focus will be the demand sites, while in another, it will be the water supplies in a region of interest. In yet other cases, it may be necessary to conceive of both a set of demand sites and the specific river system together as the study area. Study area boundaries could be somewhat more flexible than the rigid definition of the hydrologic boundaries in order to include the adjacent demand areas served by water supplies from within the hydrologic supply system, or possibilities of importing or exporting water from or to sites outside the study area.
Whichever you choose, ultimately the study area in WEAP will contain a distinct set of information and assumptions about a system of linked demands and supplies. Several different study areas as defined in WEAP could actually be used to represent the same geographic area or watershed, each under alternative configurations or different sets of demand data or operating assumptions. In this way, study areas can be thought of as representing separate databases where different sets of water supply and demand data are stored, managed and analyzed.
To begin your analysis, you will first create a new area. To do so, choose Area, Create Area... from the Main Menu. When creating a new area, you can begin with a copy of an existing area or start fresh with a blank area. If starting from a blank area, you will be prompted to Set Area Boundaries. You may specify a password to protect an area. When specifying a password, use the radio buttons to indicate whether the password is required to open the area, or whether it is required only to save changes to the area. When no password is specified, the area can be freely opened and changed. (Note: Do not rely on this password to protect proprietary or sensitive information -- WEAP does not encrypt the data files, which means that anyone who knows how to read a NexusDB database file can read the information.) Finally, enter a brief description of the new area. You can edit this description later in the Manage Areas screen.
Another way to create an area as a copy of an existing area is from the Main Menu: Area, Save As....
See also: Manage Areas