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Water Quality : Reach Water Quality
Water Quality
Reach Water Quality
The current implementation of the reach allows the user to model salinity with a simple well-mixed method or a discretized method. Temperature along with any combination of dissolved oxygen and salinity can also be modeled with the discretized methods.
On the reach, slots are added when a method from the Water Quality Routing category is selected (usually automatically based on the Reach Water Quality method); the available Water Quality Routing methods depend on the selected Reach Water Quality method and physical routing method. As a result, the documentation is organized by first listing all the slots, then the user-selectable methods, beginning of run behavior, dispatch slots and finally dispatch methods. Each method specifies whether it is valid for the well mixed or discretized set of methods.
Slots
Following is a list of all of the water quality slots used by the Reach. The slots are instantiated by the selected method in the Water Quality Routing category. Each of those methods list the slots that are instantiated.
Temperature Slots
 Inflow Heat
Type: Multi Slot
Units: Heat
Description: holds the values of inflow heat for each inflow to the reservoir
I/O: Required Known
 Diversion Temperature
Type: Series Slot
Units: Temperature
Description: temperature of Diversion
I/O: Optional input
 Return Flow Temperature
Type: Series Slot
Units: Temperature
Description: temperature of Return Flow.
I/O: Optional input
 Local Inflow Temperature
Type: Series Slot
Units: Temperature
Description: temperature of Local Inflow.
I/O: Optional input
 Maximum Flow Rate for WQ Stability
Type: Table Slot
Units: Flow
Description: Input a flow rate which is greater then or equal to any anticipated for the simulation to keep the explicit solution stable.
Note:  Extremely large values will significantly increase computational cost.
I/O: Input only
 Outflow Heat
Type: Series Slot
Units: Heat
Description: temperature of releases from the reservoir
I/O: Output only
 Dispersion Coefficient
Type: Table Slot
Units: None
Description: longitudinal dispersion coefficient in units of L2/T
Information: used in temperature calculation
I/O: input only
 Specific Heat of Water
Type: Table Slot
Units: SpecificHeat
Description: specific heat of water. Used for heat / temperature conversions.
I/O: optional input
 Distributed Temperature Output
Type: Table Series Slot
Units: Various
Description: Table which displays the discretized values Water temperature with respect to distance within the Reach.
I/O: Output only - This is a temporary slot that is not saved in the model file.
 Distributed Total Surface Flux Output
Type: Table Series Slot
Units: Various
Description: Table which displays the discretized values of the main components of surface heat exchange as well as the total surface flux with respect to distance.
I/O: Output only - This is a temporary slot that is not saved in the model file.
 Air Temperature
Type: Series Slot
Units: Temperature
Description: air temperature at the reservoir surface
I/O: Input only
 Dewpoint Temperature
Type: Series Slot
Units: Temperature
Description: dewpoint temperature at the reservoir surface
I/O: Required input
 Incoming Solar Radiation
Type: Series Slot
Units: HeatFlux
Description: incoming solar radiation received by the reservoir
I/O: Required Input
 Wind Velocity
Type: Series Slot
Units: Velocity
Description: wind velocity at reservoir surface
Information: This slot is assumed to be zero if not a user input.
I/O: Optional input
 Distributed Temperature Output
Type: Table Series Slot
Units: Various
Description: Table which displays the discretized values Water temperature with respect to distance within the Reach.
I/O: Output only - This is a temporary slot that is not saved in the model file.
Salinity Slots
 Inflow Salt Mass
Type: Series Slot
Units: Mass
Description: holds the values of inflow salinity for each inflow to the reach
I/O: Required known
 Outflow Salt Mass
Type: Series Slot
Units: Mass
Description: salt mass in outflow from the reservoir
I/O: Output only
 Seepage Salt Concentration
Type: Series Slot
Units: Concentration
Description: Salt concentration of the Seepage
I/O: Input, set by a rule, or propagated across a link.
 Diversion Salt Concentration
Type: Series Slot
Units: Concentration
Description: salt concentration of Diversion.
I/O: Input, Output, or set by a rule.
 Return Flow Salt Concentration
Type: Multi Slot
Units: Concentration
Description: salt concentration of Return Flow.
Information: When there are multiple links to this slot, the subslots will be shown. The first column is the sum column, which is not relevant as these are concentrations not mass.
I/O: Input, rules, or propagated from another object
 Local Inflow Salt Concentration
Type: Series Slot
Units: Concentration
Description: salt concentration of Local Inflow.
I/O: Input, rules, solved for by dispatch method, or propagated from another object
 Distributed Salt Concentration Output
Type: Table Series Slot
Units: Various
Description: Table which displays the discretized values of Salt Concentration with respect to distance within the Reach.
I/O: Output only - This is a temporary slot that is not saved in the model file.
 Inflow Salt Concentration
Type: Series Slot
Units: Concentration
Description: holds the values of inflow salinity for inflow to the reach
I/O: Required known
 Seepage Salt Mass
Type: Series Slot
Units: Mass
Description: Salt Mass of the Seepage
I/O: Output only
 Return Flow Salt Mass
Type: Multi Slot
Units: Mass
Description: salt mass of Return Flow.
I/O: Optional known
 Diversion Salt Mass
Type: Series Slot
Units: Mass
Description: The salt mass value of the Diversion from the reach
I/O: Output only
 Local Inflow Salt Mass
Type: Series Slot
Units: Mass
Description: The salt mass value of the Local Inflow
I/O: Output Only
 Outflow Salt Concentration
Type: Series Slot
Units: Concentration
Description: salinity of releases from the reservoir
I/O: Output only
 Salt Mass Removal
Type: Series Slot
Units: Mass
Description: The mass of salt removed from the reach, typically by a linked Agg Diversion Site. This is included into the reach’s salinity mass balance. A positive Salt Mass Removal represents salt removed from (subtracted from) the Outflow Salt Mass.
I/O: Optional input, if not linked and not input, defaults to zero
 Salt Available For Removal
Type: Series Slot
Units: Mass
Description: The maximum salt mass that can be removed without dropping below the specified Minimum Salt Concentration (if solving downstream) or exceeding the specified Maximum Salt Concentration (if solving upstream). If this slot is not linked, it is not used.
I/O: Output only
 Salt Storage
Type: Series Slot
Units: Mass
Description: The mass of salt stored on the reach due to low flows
I/O: Initial timestep can be input, otherwise Output only.
 Maximum Salt Concentration
Type: Periodic Slot
Units: Concentration
Description: The maximum possible salt concentration; i.e. the concentration at saturation
I/O: Input
 Minimum Salt Concentration
Type: Periodic Slot
Units: Concentration
Description: The minimum possible salt concentration. There is no restriction on the value in this slot. It can be negative.
I/O: If the Salt Mass Removal slot is linked, this slot is required input. Otherwise it is an optional input.
 Diversion Salt Concentration Maximum
Type: Series Slot with Periodic Input
Units: Concentration
Description: The maximum possible salt concentration on the diversion.
I/O: Optional input. Can be specified as a periodic or series relationship
Dissolved Oxygen Slots
 Inflow Dissolved Oxygen Mass
Type: Multi Slot
Units: Mass
Description: holds the values of inflow dissolved oxygen for each inflow to the reservoir
I/O: Input, rules, or propagated across a link
 Inflow Detritus Mass
Type: Multi Slot
Units: Mass
Description: holds the values of inflow detritus for each inflow to the reservoir
I/O: Input, rules, or propagated across a link
 Inflow Dissolved Organics Mass
Type: Multi Slot
Units: Mass
Description: holds the values of inflow dissolved oxygen for each inflow to the reservoir
I/O: Input, rules, or propagated across a link
 Inflow Ammonia Mass
Type: Multi Slot
Units: Mass
Description: holds the values of inflow ammonia for each inflow to the reservoir
I/O: Input, rules, or propagated across a link
 Outflow Dissolved Oxygen Mass
Type: Series Slot
Units: Mass
Description: dissolved oxygen mass in Outflow from the reach
I/O: Output only
 Outflow Detritus Mass
Type: Series Slot
Units: Mass
Description: detritus mass in Outflow from the reach
I/O: Output only
 Outflow Dissolved Organics Mass
Type: Series Slot
Units: Mass
Description: dissolved oxygen mass in releases from the reach\
I/O: Output only
 Outflow Ammonia Mass
Type: Series Slot
Units: Mass
Description: ammonia mass in the outflow from the reach
I/O: Output only
 Diversion Detritus Concentration
Type: Series Slot
Units: Concentration
Description: detritus concentration of Diversion.
Information:  
I/O: Output only
 Return Flow Detritus Concentration
Type: Series Slot
Units: Concentration
Description: detritus concentration of Return Flow.
I/O: Input, rules, solved for, or propagated across a link.
 Local Inflow Detritus Concentration
Type: Series Slot
Units: Concentration
Description: detritus concentration of Local Inflow.
I/O: Input, rules, solved for, or propagated across a link.
 Diversion Diss Org Concentration
Type: Series Slot
Units: Concentration
Description: dissolved organics concentration of Diversion.
I/O: Input, rules, solved for, or propagated across a link.
 Return Flow Diss Org Conc
Type: Series Slot
Units: Concentration
Description: dissolved organics concentration of Return Flow.
I/O: Input, rules, solved for, or propagated across a link.
 Local Inflow Diss Org Concentration
Type: Series Slot
Units: Concentration
Description: dissolved organics concentration of Local Inflow.
I/O: Input, rules, solved for, or propagated across a link.
 Diversion Ammonia Concentration
Type: Series Slot
Units: Concentration
Description: detritus concentration of Diversion.
I/O: Input, rules, solved for, or propagated across a link.
 Return Flow Ammonia Concentration
Type: Series Slot
Units: Concentration
Description: detritus concentration of Return Flow.
I/O: Input, rules, solved for, or propagated across a link.
 Local Inflow Ammonia Concentration
Type: Series Slot
Units: Concentration
Description: ammonia concentration of Local Inflow.
I/O: Input, rules, solved for, or propagated across a link.
 Diversion DO Concentration
Type: Series Slot
Units: Concentration
Description: dissolved oxygen concentration of Diversion.
I/O: Input, rules, solved for, or propagated across a link.
 Return Flow DO Concentration
Type: Series Slot
Units: Concentration
Description: dissolved oxygen concentration of Return Flow.
I/O: Input, rules, solved for, or propagated across a link.
 Local Inflow DO Concentration
Type: Series Slot
Units: Concentration
Description: dissolved oxygen concentration of Local Inflow.
I/O: Input, rules, solved for, or propagated across a link.
Total Dissolved Gas Slots
 Inflow TDG Concentration
Type: Series
Units: Fraction
Description: TDG concentration of the Inflow
I/O: Input or output
 Outflow TDG Concentration
Type: Series
Units: Fraction
Description: TDG concentration of the Outflow
I/O: Output only
 TDG Lag Time
Type: Scalar
Units: Time
Description: The amount of time the TDG concentration should be lagged from the Inflow to the Outflow
I/O: Required Input
 Number of TDG Dispersion Coefficients
Type: Scalar
Units: None
Description: The number of coefficients used to model TDG dispersion; the slot value must be an integer greater than or equal to 1, and it must equal the number of rows in the TDG Dispersion Coefficients slot.
I/O: Required Input
 TDG Dispersion Coefficients
Type: Table
Units: None, Fraction
Description: Coefficients used to model TDG dispersion; the first column contains the Lag Time Offset values, which must be integers in sequential order. The second column contains the Coefficients, which must sum to one. The Lag Time Offset is added to the TDG Lag Time to determine the timestep for which the Coefficient is applied to the Inflow TDG Concentration.
I/O: Required Input
 Lagged Dispersed TDG Concentration
Type: Series
Units: Fraction
Description: The calculated TDG concentration after lagging and dispersion have been applied to the Inflow TDG Concentration, before Dissipation has been applied
I/O: Output only
 TDG Dissipation Coefficient
Type: Scalar
Units: None
Description: A coefficient applied to the Lagged Dispersed TDG Concentration to calculate the TDG Dissipation
I/O: Required Input if TDG Dissipation is not specified
 TDG Dissipation Adjustment
Type: Scalar
Units: Fraction
Description: An adjustment or correction factor that is subtracted in the TDG Dissipation calculation (a positive value increases the Outflow TDG Concentration)
I/O: Optional input, defaults to zero
 TDG Dissipation
Type: Series
Units: Fraction
Description: The decrease in TDG concentration while in transit, subtracted from the Lagged Dispersed TDG Concentration to compute the Outflow TDG Concentration
I/O: Input or Output
 Delta Inflow
Type: Series
Units: Flow
Description: This slot represents the optimization variable for Delta Inflow
 Delta Outflow
Type: Series
Units: Flow
Description: This slot represents the optimization variable for Delta Outflow.
 Delta Inflow TDG Concentration
Type: Series
Units: Fraction
Description: This slot represents the optimization variable for Delta Inflow TDG Concentration.
 Delta Outflow TDG Concentration
Type: Series
Units: Fraction
Description: This slot represents the optimization variable for Delta Inflow TDG Concentration.
Revised: 11/11/2019