Min Bypass
The methods in this category specify whether a minimum bypass is required when making water rights allocations and are executed as part of a prioritized water rights allocation. These methods model a legal constraint that may reduce a water right’s initial request for water by forcing the water right to leave a certain amount of water in the stream at a given reference location.
NoneNo minimum bypass is defined for this account.
Fraction of Flow Above MinSlots Specific to This Method
Bypass Reference Location
Type: List
Units: NA
Alternate Units: NA
Description: Optional, control point at which you want to keep a minimum bypass in the stream. If a control point is not specified in this slot, the accounting flow in the linked object will be used.
I/O: Input only, only one control point can be specified
Links: No
Absolute Min Bypass
Type: Periodic
Units: TIME vs Flow
Alternate Units: NA
Description: The required flow that must remain in the stream
I/O: Input only
Links: No
Fraction above Min
Type: Periodic
Units: Time vs none
Alternate Units: NA
Description: The fraction of the flow above the Absolute Min Bypass that must be left in the stream
I/O: Input only
Links: No
Method Details
The requirement contains two components, the Absolute Min Bypass and the Fraction above Min.
• A legal requirement says to leave 300cfs in the stream. The following would be input: Absolute Min Bypass = 300cfs, Fraction above Min = 0. • A legal requirement says to leave 45% of the flow in the stream. Input the following: Absolute Min Bypass = 0cfs, Fraction above Min = 0.45 • A legal requirement says to leave 300cfs plus 45% of the flow above that minimum in the stream. Input the following: Absolute Min Bypass = 300cfs, Fraction above Min = 0.45. |
This method is used to specify the flow to leave in the supply chain. This location can be specified in two ways depending on whether a control point is specified in the Bypass Reference Location:
• If the there is a control point specified in the Bypass Reference Location, the accounting flows on that object will be used.
• If there is no control point specified in the Bypass Reference Location, then the accounting flows on the object supplying the allocation will be used. That is, for an allocation to a diversion account from reach, the amount of water available for appropriation from passthrough accounts on the reach will be used.
The required bypass flow is calculated using the:
• Sum of Temp Available for Appropriation slot for all passthrough accounts on the object (non-control points), or
• Sum of Outflow for all passthrough accounts at the control point reference location.
If the reference location is downstream, then any lags and/losses are applied so that the min bypass constraint includes enough water to meet the min bypass at the reference location. Then, the constraint (that is, upper limit on the appropriation) is temporarily stored in the Temp Min Bypass Constraint slot on the diversion account but is not saved with the model file.
Revised: 07/17/2020