Surface-Water Flags |
Surface-Water Flags |
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This pane is a subpane of the FMP: Farm Process pane on the MODFLOW Packages and Programs dialog box.
In the Farm process, there is a distinction between routed deliveries, semi-routed deliveries, and non-routed deliveries.
Routed deliveries of water are from streams flowing through a farm. It is assumed that the water is extracted from the reach that is furthest upstream.
Semi routed deliveries of water are also from streams but the point of diversion need not be in a cell in a farm. The modeler specifies from which reach water is diverted.
Non-routed deliveries are not associated with streams or with any other particular method for transporting the water to the farm.
A farm can have either routed or semi-routed deliveries but not both. A farm can have any number of non-routed deliveries.
IRDFL allows the modeler to decide how routed surface water deliveries should be handled. Modelers have three choices:
•None (0): No routed deliveries will be simulated. Semi-routed deliveries may still be simulated.
•From a diversion segment (1): Routed deliveries will only be from segments that are diversions.
•From any segment (-1): Routed deliveries can be from from any segment.
IRRFL allows the modeler to decide how the return flow from routed surface water deliveries should be handled. Modelers have two choices:
•To a nondiversion segment (1):
•To any segment (-1):
(If no routed deliveries are simulated (IRDFL = 0) or the SFR package is not used, IRRFL will be automatically set to 0 meaning "no return flow.")
•None (0): No surface water is available for irrigation
•Equal (1): An equal allotment height will be available to all farms. The allotments are specified in the Farm Allotment dialog box.
•Prior appropriation with calls (2): A prior appropriation system will be used to allocate surface water. Each farm will have a maximum amount that it can use. Upstream farms with more junior rights must reduce their diversions to allow the more senior farm to divert this amount.
•Prior appropriation without calls (3): A prior appropriation system will be used to allocate surface water. However, there is no set amount that each farm can use.
An iterative process is used to allocate water among farms when a prior appropriate system is used. PCLOSE is the closure criterion for that process. PCLOSE has units of L3/T.