release.txt


                           SWR Process Release Notes


This file describes changes introduced into the SWR Process with each 
official release; these changes may substantially affect users.


NOTE: Any use of trade, product or firm names is for descriptive purposes
only and does not imply endorsement by the U.S. Government.


o Version 1.0 09/10/2012:

This version is the initial release.

o Version 1.01.0 10/17/2012:

The SWR Process was modified to allow incorporation of SWR derivative terms 
into the groundwater flow equation solved by MODFLOW-NWT. The SWR Process 
was also modified to allow downstream discharge from a SFR2 reach to be routed 
to a SWR reach using an additional SWR surface-water control structure. The 
SWR Process was also modified to allow surface-water control structures 
discharging from the SWR1 network to discharge to SFR2 reaches.

Modified input instructions for the SWR1 input file

Items 0-1a: As in previous versions of the code.

1b.  CSWROPT [IOPTUNIT]

USE_IMPLICIT_NEWTON_CORRECTION keyword for implicitly calculating the
  Newton correction term for the groundwater flow equation. This option
  requires solving SWR1 equations using the current and perturbed heads.
  As a result, SWR1 Process runtimes will be approximately a factor of 2
  greater.

USE_EXPLICIT_NEWTON_CORRECTION keyword for explicitly calculating the
  Newton correction term for the groundwater flow equation. This option
  calculated the Newton correction terms using the current SWR1 stage
  solution and current and perturbed heads within the aquifer-reach 
  exchange calculation routine (SSWR_CALC_QAQ). This option does not have 
  a significant effect on SWR1 Process runtimes and is sufficient for the 
  test problems evaluated.

By default, Newton corrections are not calculated. Only one of the keywords
  specified above should be used if Newton correction terms for the SWR1
  Process are desired.

Items 2-4c: As in previous versions of the code.

4d.  ITAB CTABTYPE CINTP [CTABRCH] [ITABRCH(1)...ITABRCH(NTABRCH)]
     
ITAB     - Number of tabular data item. ITAB value is the tabular data item
           that will be referred to by CSTRCRIT and CSTRVAL in Item 13b. 
           Tabular data items specified in Item 4d do not need to be specified 
           in numerical order.
CTABTYPE - No changes
CINTP    - No changes
CTABRCH  - No changes
ITABRCH  - No changes

Items 5-12: As in previous versions of the code.

13a. ISTRRCH ISTRNUM ISTRCONN ISTRTYPE [NSTRPTS] [STRCD] [STRCD2] [STRCD3] 
     [STRINV] [STRINV2] [STRWID] [STRWID2] [STRLEN] [STRMAN] [STRVAL] [ISTRDIR]
     [ISFRSEG] [ISFRRCH]
     
ISTRRCH  - No changes
ISTRNUM  - Must be 0 if: (1) ISTRTYPE=11; or (2) SFR is specified in the MODFLOW-NWT name
           file and ISFRSEG and ISFRRCH > 0. No changes otherwise.
ISTRTYPE - ISTRTYPE=11 for a inflow structure from SFR2 segment ISFRSEG and reach ISFRRCH. 
           ISTRCONN must be 0 if ISTRTYPE=11. All other surface-water control structures
           detailed in the documentation report are available.
NSTRPTS  - No changes
STRCD    - No changes
STRCD2   - No changes
STRCD3   - No changes
STRINV   - No changes
STRINV2  - No changes
STRWID   - No changes
STRWID2  - No changes
STRLEN   - No changes
STRMAN   - No changes
STRVAL   - No changes
ISTRDIR  - No changes
ISFRSEG  - SFR2 segment that (1) supplies downstream segment discharge to SWR1 reach 
           ISTRRCH or (2) SFR2 segment that receives SWR2 surface-water control 
           structure discharge. ISFRSEG is not read if SFR is not specified in the 
           MODFLOW-NWT name file.
ISFRRCH  - SFR2 reach in SFR2 segment ISFRSEG that receives SWR2 surface-water control  
           structure discharge. Any SFR2 reach number can be specified if ISTRTYPE=11.
           ISFRRCH is not read if SFR is not specified in the MODFLOW-NWT name file.

Items 13b-15: As in previous versions of the code.

Reference:

Hughes, J.D., Langevin, C.D., Chartier, K.L., and White, J.T., 2012, 
Documentation of the Surface-Water Routing (SWR1) Process for modeling 
surface-water flow with the U.S. Geological Survey Modular Ground-Water
Model (MODFLOW–2005): U.S. Geological Survey Techniques and Methods, 
book 6, chap. A40 (Version 1.0), 113 p.


Contact:

    Joseph D. Hughes
    Florida Water Science Center
    4446 Pet Lane
    Suite 108
    Lutz, FL 33559
    jdhughes@usgs.gov