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Objects and Methods : Diversion Object : User Methods : Diversion Request
Diversion Request
Used to specify how Diversion Request is calculated.
* Input Diversion Request
Use this method if you want to input the Diversion Request. No calculations are performed in this method.
There are no slots specific to this method.
* Percent of Available
Used to calculate Diversion Request as a percentage of the available water.
    
Slots Specific to This Method
 Percent of Available to Divert
Type: SeriesSlot
Units: fraction
Description: Percentage of available water to be diverted
Information: Must be between 0% and 100%
I/O: Required input
* Periodic Diversion Request
This method is used to specify the Diversion Request as a function of date/season using a periodic slot.
Slots Specific to This Method
 Periodic Diversion Request
Type: Periodic Slot
Units: flow
Description: Diversion request as a function of date/season
Information: The Diversion Request is computed at the beginning of each timestep using the current date to look up the value from this slot.
I/O: Required input
Method Details  
The Periodic Diversion Request method executes at the beginning of the run. Each timestep in the run is used to look up a value in the Periodic Diversion Request slot. The computed value is set in the Diversion Request slot.
* Reservoir Level Lookup
The Reservoir Level Lookup method is used to compute the Diversion Request as a function of the date/season and the operating level of a specified reservoir.
Slots Specific to This Method
 Level vs Diversion Request
Type: Periodic Slot
Units: flow
Description: Diversion request as a function of reservoir level and date/season
Information: Each column corresponds to a reservoir’s operating level. For each operating level, the diversion request is specified for each date range in the periodic slot.
I/O: Required input
 Diversion Request Reservoir
Type: List Slot
Units: none
Description: Reservoir used to compute the diversion request
Information: The previous timestep operating level of this reservoir is used to look up the diversion request in the Level vs Diversion Request slot.
I/O: Required input
 Forecast Period
Type: Scalar
Units: none
Description: A number of timesteps, including the current simulation timestep, used in the algorithms for calculating forecasted hydrology, regulation discharge and flood releases. This can be propagated from a computational subbasin of which the control point is a member.
Information: This slot must be input and greater than or equal to 1. If a Forecast Period is not necessary and you wish to only consider the current timestep, input a value of 1.
Information: Required Input
Method Details  
Note:  If the specified reservoir is disabled and set to Pass Inflows, no request lookup is possible. See Diversions Based on Disabled Reservoirs in USACE‑SWD Modeling Techniques for details on the behavior in this situation.
The Reservoir Level Lookup method executes at the beginning of each timestep.
For each timestep (t) in the forecast period, the Diversion Request Reservoir’s previous timestep’s (current timestep – 1) operating level, and the forecast timestep’s date (t) are used to look up the diversion request value in the Level vs Diversion Request slot.
This value is set on the Diversion Request slot. The Diversion is limited by the Maximum Diversion value. Because the method uses the same operating level (from the previous timestep) for all timesteps in the forecast period, it is only an approximation but allows the object to solve throughout the forecast period.
Revised: 08/02/2021