Network Tab

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The Network tab is on the SFR: Stream-Flow Routing package pane of the MODFLOW Features tab of the Object Properties dialog box. It is used to specify how stream segments are linked to one another.

The Starting time and Ending time of each time period is specified on the Time tab

Outflow segment (OUTSEG)

If a stream flows into another stream or lake, OUTSEG is used to identify the downstream stream or lake that receives the flow. A positive value indicates that a stream will receive the flow. A negative value indicates that a lake will receive the flow. Clicking the Closest button in the cell for OUTSEG will set OUTSEG to indicate the Lake ID or Segment Number of the nearest downstream lake or stream. If this segment does not feed (or discharge into) another downstream segment, then enter a value of "0" for this variable. If the segment ends within the modeled grid and OUTSEG = 0, outflow from the segment is not routed anywhere and is no longer part of the stream network. One may wish to use this if all flow in the stream gets diverted into a lined canal or into a pipe. See also: Link Streams dialog box.

Diversion segment (IUPSEG)

If a stream diverts water from an upstream stream or lake, IUPSEG identifies the upstream segment or lake from which water is diverted (or withdrawn) to supply inflow to this stream segment. A positive value indicates that the flow is diverted from a stream. A negative value indicates the flow is diverted from a lake. If this stream segment does not receive inflow as a diversion from an upstream segment, then set IUPSEG = 0. Clicking the Closest button in the cell for IUPSEG will set IUPSEG to indicate the Lake ID or Segment Number of the nearest upstream lake or stream.

Diversion priority (IPRIOR)

An integer value that only is specified if flow is diverted from another stream segment. IPRIOR defines the prioritization system for diversion. The prioritization system is used when insufficient water is available to meet all diversion stipulations, and is used in conjunction with the value of FLOW (specified on the Flows tab).

•When IPRIOR = 0, then if the specified diversion flow (FLOW) is greater than the flow available in the stream segment from which the diversion is made, the diversion is reduced to the amount available. This will leave no flow available for tributary flow into the segment into which it would naturally flow.

•When IPRIOR = -1, then if the specified diversion flow (FLOW) is greater than the flow available in the stream segment from which the diversion is made, no water is diverted from the stream. This approach assumes that once flow in the stream is sufficiently low, diversions from the stream cease. This is the “priority” algorithm that originally was programmed into the STR1 Package (Prudic, 1989).

•When IPRIOR = -2, then the amount of the diversion is computed as a fraction of the available flow in segment IUPSEG; in this case, 0.0 < FLOW < 1.0.

•When IPRIOR = -3, then a diversion is made only if the streamflow leaving segment IUPSEG exceeds the value of FLOW. If this occurs, then the quantity of water diverted is the excess flow and the quantity that flows from the last reach of segment IUPSEG into its normal downstream segment (OUTSEG) is equal to FLOW. This represents a flood-control type of diversion, as described by Danskin and Hanson (2002).