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Objects and Methods : Reach : User Methods : Reach Bank Storage
Reach Bank Storage
The Reach Bank Storage category is used to model flow to/from storage within a reach. The Bank Storage Return is added/removed from the reach after the flow is routed but before Gain Loss is calculated.
The Reach Bank Storage category is available for all Routing methods except time lag methods.
* None
This is the default method. It performs no bank storage calculations.
There are no slots specific to this method.
* Average Flow Bank Storage
This method is designed to simulate hyporheic zone storage and return on Reach objects. It is similar to the bank storage on reservoir objects. The amount of bank storage is calculated as a function of flow rate.
Slots Specific to This Method
 Average Flow Coefficient
Type: Table
Units: No Units
Description: A coefficient based on transmissivity of the surrounding aquifer and the relationship between river stage and flow rate
Information: Although the slot does not have a formal unit, the value in the slot has conceptual units of square root of seconds. Often this value is negative based on the equation below.
I/O: Required input
 Bank Storage Return
Type: Series
Units: FLOW
Description: The rate of return to the reach from bank storage
Information: A positive number represents a return to the reach while a negative number represents a loss to bank storage.
I/O: Output only
 Routed Flow
Type: Series
Units: Flow
Description: Flow rate used to calculate Bank Storage Return
Information: This represents the flow rate in the reach after Local Inflow, Seepage, and Diversion are added/removed and the flow is routed.
I/O: Output only
 Timesteps to Average
Type: Table
Units: No Units
Description: An integer number of timesteps to compute the average flow. This value must be greater than zero
I/O: Required input
Method Details 
The routed flow average is the average flow over the number of timesteps specified in Timesteps to Average prior to the current timestep. For the first (timesteps to average - 1) timesteps, some routed flows are being set on timesteps prior to the initial timestep. These values, set equal to the routed flow at the initial timestep, are used so that calculations for routed flow average don’t used routed flows equal to zero. A warning message will remind users this is occurring.
Revised: 01/11/2023