Reservoirs are nodes that represent an infinite external source or sink of water to the network. They are used to model such things as lakes, rivers, groundwater aquifers, and tie-ins to other systems. Reservoirs can also serve as water quality source points.
The primary input properties for a reservoir are its hydraulic head and initial water quality. Because a reservoir is a boundary point to a network, its head and water quality cannot be affected by what happens within the network. Therefore it has no computed output properties. However its head can be made to vary with time by assigning a time pattern to it.
Below is the list of Reservoir properties.
| Field | Description |
| Reservoir ID | A unique label used to identify the reservoir. |
| X-Coordinate | Horizontal location of the junction on the Study Area Map. If left blank then the junction will not appear on the map. |
| Y-Coordinate | Vertical location of the junction on the Study Area Map. If left blank then the junction will not appear on the map. |
| Total Head | The hydraulic head (elevation + pressure head) of water in the reservoir. This is a required property. |
| Head Pattern | The ID label of a time pattern used to model time variation in the reservoir's total head. Leave blank if none applies. This property is useful if the reservoir represents a tie-in to another system whose pressure varies with time. |
| Initial Quality | Water quality level at the reservoir. Can be left blank if no water quality analysis is being made or if the level is zero. |
| Source Quality | Quality of water entering the network at this location. |