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Water Quality : Reservoir Water Quality : User Methods : WQ Distribute Inflow
WQ Distribute Inflow
This category of methods is only applicable to the layered methods. These methods define how the incoming water from the Inflow and side flows (e.g., canal flow, hydrologic inflow, etc.) is distributed into the reservoir. For example, it may be a function of density, temperature, etc., and may be “allocated” into one or more of the reservoir layers.
* None
This is the default method and is not a valid method for calculation. An error is flagged if this method executes. This method does not instantiate any water quality slots.
* By Temperature
No slots are explicitly instantiated by this method but the following slots are used as a part of the calculation.
Slots With Required Known Data
• Total Inflows
• Temperature
This method requires a current total inflow temperature, a previous epilimnion temperature, and a previous hypolimnion temperature, all are columns of the Temperature Agg Series Slot.
Slots With Output Data
• Inflow to Epilimnion
• Inflow to Hypolimnion
Method Details  
The method, distributeInflowbyTemp, compares the average total inflow temperature and distributes the total inflow based on a simple linear weighting scheme. In general, if the temperature is between the temperatures of the epilimnion and hypolimnion, the total inflow is split by a linear ratio of the total inflow temperature to the temperature difference between the two layers. If the total inflow temperature is greater or less than both layer’s temperatures, the total inflow is totally allocated to the layer with the more similar temperature.
The following is more detail on the algorithm. Only one of the following options will be selected by the algorithm
• If previous epilimnion and hypolimnion temperatures are very close (within 0.1C) distribute the total inflow to each layer based on previous layer volumes.
• If the Total Inflow Temperature is greater than the previous epilimnion temperature, distribute all of the Total Inflow to the top layer, the epilimnion.
• If Total Inflow Temperature is less than the previous hypolimnion temp, distribute all of the Total Inflow to the bottom layer, the hypolimnion.
• If Total Inflow Temperature is between the previous epilimnion and hypolimnion temperatures, distribute the Total Inflow using a weighted ratio based on previous layer temperatures and the current Total Inflow Temperature.
* Specify Distribution
No slots are explicitly instantiated by this method, but the following slots are used as a part of the calculation:
• Total Inflows
• Inflow to Hypolimnion
• Inflow to Epilimnion
The method distributes the Total Inflow based on the values in either the Inflow to Hypolimnion or Epilimnion slots. One or the other of these must be specified but not both or an error will occur.
* Specify Fraction
This method allows you to distribute the inflows using a series of fractions. The following slot is added by this method.
 Inflow to Hypolimnion Fraction
Type: Series with Periodic Input
Units: Fraction
Description: The fraction of the total inflow that enters the Hypolimnion
Information: The value must be specified and the value must be between 0 and 1, inclusive.
I/O: Required via input or Rules
The distribution is computed as follows:
(14.3)    Inflow to Hypolimnion = Inflow to Hypolimnion Fraction * Total Inflows
(14.4)    Inflow to Epilimnion = Total Inflows - Inflow to Hypolimnion;
Revised: 11/11/2019