A reservoir is the impoundment created behind dams, or behind navigation locks and dams. For HEC-WAT a reservoir also includes the dam built on a stream to store water for uses such as flood risk management, hydroelectric power generation, recreation use, and water supply, etc.
To add a reservoir:
From the Schematic Map Window, use the Zoom Tool and Pan Tool to find the location where a reservoir needs to be added (e.g., Lake Mendocino), press the Reservoir Tool.
Hold down the CTRL key and click on the stream alignment to place the upstream end of the reservoir. Release the CTRL key; drag the mouse to the downstream end of the reservoir and click.
The Name New Reservoir dialog box will open. Enter the new Name (Lake Mendocino) and Description (optional, but recommended). Click OK, the Name New Reservoir dialog box will close.
The reservoir will now appear on the schematic as a cyan triangle (reservoir pool), a blue line (storage reach), a gray rectangle (dam), and two common computation points that represent the upstream and downstream ends of the reservoir.
The default representation of the reservoir pool is a triangle; the user can edit this triangle if a more detailed representation of the pool is desired. With the Reservoir Tool pressed, double-click on the reservoir. The triangle will now be green with a blue outline color. Also, there are three vertex points (blue), and at the apex of the triangle is the reservoir label, which is represented by a yellow circle.
When a reservoir is created there are two common computation points that are created with default names. It is recommended that the names of the two common computation points be changed. These two common computations points represent the inflow and outflow junctions of the reservoir and should be renamed accordingly.
To change the name of a common computation point, press the Computation Point Tool , right-click on one of the common computation points (e.g., the upstream CCP for Lake Mendocino). From the shortcut menu, click Rename Computation Point; the Rename Computation Point dialog box will open. In the Name box, enter the new name, and in the Description box enter a description (optional, but recommended). For example, rename the CCP for the inflow junction for Lake Mendocino as Lake Mendocino Inflow Jct.
Click OK, a Confirm Rename window will open, asking the user to be sure that the CCP is to be renamed. Click Yes, the Rename Computation Point dialog box will close and the new name for the CCP will appear in the map window.
Repeat this step to rename the CCP outflow junction. For example, rename the outflow CPP junction as Lake Mendocino Outflow Jct.
Repeat the steps above for the Lake Sonoma reservoir.
