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Objects and Methods : Level Power Reservoir : User Methods : Incremental Hydrologic Inflows on Subbasin
Incremental Hydrologic Inflows on Subbasin
The Incremental Hydrologic Inflows on Subbasin category contains methods used to specify that the reservoir has cumulative inflows that must be disaggregated into incremental inflows. There are two methods: Full Run and Forecast Period. The disaggregation is actually executed from the computational subbasin containing the reservoir. See Incremental Local Inflows for details.
When the Input Hydrologic Inflow method is selected in the Hydrologic Inflow category, the Full Run becomes available. The method contains two slots: Cumulative Hydrologic Inflow and Incremental Hydrologic Inflow for the reservoir. Data must be input into the Cumulative Hydrologic Inflow slots. The computational subbasin will execute the Compute Full Run Incremental Hydrologic Inflows method and set the Incremental Hydrologic Inflow slots as input. Setting the Incremental Hydrologic Inflow slots as input prevents the slot values from being cleared in future model runs when the subbasin is disabled. The computational subbasin will first check that Full Run method has been selected on all reservoirs in the basin. During the model run, when the reservoir dispatches, the Full Run method will copy the value in the Incremental Hydrologic Inflow slot and set the Hydrologic Inflow slot.
When a forecast method is selected in the Generate Forecast Hydrology methods on the reservoirs, a new method will be available within the Incremental Hydrologic Inflows on Subbasin category: Forecast Period. This method will contain the Cumulative Hydrologic Inflow slot. When this method is selected the computational subbasin will execute the Compute Forecast Period Incremental Hydrologic Inflows method and set the Hydrologic Inflow slots.
* None
This method is the default for the Incremental Hydrologic Inflows on Subbasin category and should be selected when hydrologic inflow data is not cumulative or the computation of incremental hydrologic inflows is not desired.
There are no slots specific to this method.
* Full Run
The Full Run method is available from the Incremental Hydrologic Inflows on Subbasin method category on the reservoirs (storage reservoir, level power reservoir, and sloped power reservoir). This method is only available if the Input Hydrologic Inflow method is selected in the Hydrologic Inflow category. This method holds the slots necessary for the computation of incremental hydrologic inflows that is performed by the computational subbasin. The method contains two slots: Cumulative Hydrologic Inflow and Incremental Hydrologic Inflow. These slots will be accessed by the computational subbasin when executing the Compute Full Run Incremental Local Inflows method. The computational subbasin uses input Cumulative Hydrologic Inflow values to calculate and set the Incremental Hydrologic Inflow slot. See Compute Full Run Incremental Local Inflows for details in the computational subbasin’s Incremental Local Inflows documentation. The Full Run method on the reservoir copies the results of the calculation in the Incremental Hydrologic Inflow slot values over to the Hydrologic Inflow series slot.
Slots Specific to This Method
 Cumulative Hydrologic Inflow
Type: Series
Units: Flow
Description: The cumulative hydrologic inflow to the reservoir
Information: Hydrologic inflow is cumulative either (1) between headwater control points and the first reservoir in the river system and also throughout the system between two reservoirs, or (2) throughout the entire river system.
I/O: Required input
 Incremental Hydrologic Inflow
Type: Series
Units: Flow
Description: The incremental hydrologic inflow to the reservoir
Information: This slot is set by the Calculate Incremental Flows method on the computational subbasin and represents the actual hydrologic inflow to the reservoir. If a Generate Forecast Hydrology method is selected, the Deterministic Incremental Hydrologic Inflow slot will be set to the values in this slot.
I/O: Computed and set with the Input flag
* Forecast Period
The Forecast Period method is available from the Incremental Hydrologic Inflows on Subbasin category on the reservoir. This method is only available if the Forecast Hydrologic Inflows method is selected in the Hydrologic Inflow category and one of the forecasting methods (that is, Geometric Recession, Exponential Recession, or Coefficient and Exponent) is selected in the Generate Forecast Hydrology category. If this method is selected, but the reservoir is not part of a subbasin with the appropriate methods selected, an error will be issued. The method contains two slots: Cumulative Hydrologic Inflow and Forecasted Cumulative Hydrologic Inflow. These slots will be accessed by the computational subbasin when executing the Compute Forecast Period Incremental Hydrologic Inflows method. The computational subbasin will use the user input Cumulative Hydrologic Inflow value to forecast and set the Forecasted Cumulative Hydrologic Inflow slot. It then uses this temporary value in its calculation of the incremental flows. The final result of this method (forecasted incremental hydrologic inflows) is set on the slot Hydrologic Inflow Forecast for each timestep in the forecast period.
Note:  Hydrologic Inflow is set instead if the Coefficient and Exponent method is selected). See Compute Forecast Period Incremental Local Inflows for details in the computational subbasin’s Incremental Local Inflows documentation.
Slots Specific to This Method
 Cumulative Hydrologic Inflow
Type: Series
Units: Flow
Description: The cumulative hydrologic inflow to the reservoir
Information: Hydrologic inflow is cumulative either (1) between headwater control points and the first reservoir in the river system and also throughout the system between two reservoirs, or (2) throughout the entire river system.
I/O: Required input
 Forecasted Cumulative Hydrologic Inflow
Type: Series
Units: flow
Description: the forecasted cumulative Hydrologic inflow to the control point
Information: This slot is set by the selected Generate Forecast Hydrologic Inflows method on the control point as called from the computational subbasin. It represents the cumulative Hydrologic inflow to the control point forecasted throughout the forecast period. This slot is invisible but can be viewed in the Special Results details on the Model Run Analysis tool; see Model Run Analysis—Special Results Details Dialog in USACE‑SWD Modeling Techniques.
I/O: Output only
Revised: 06/04/2022