release.txt MODFLOW-2005 Release Notes This file describes changes introduced into MODFLOW-2005 with each official release; these changes may substantially affect users. In this file, packages are referred to by their 3-or 4-character abbreviation. For information and references related to these packages, see mf2005.txt ("Summary of MODFLOW-2005"). 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 1.12.0 02/03/2017 GWF2SWR -- This is the Surface Water Routing (SWR) Process, which has been added. GWF2SWI27 -- Added FIXEDZETA option, which fixes the zeta surfaces during the simulation and does not allow them to move. Added statements that allow SWI code to be incorporated into MODFLOW-NWT. These statements are commented out. Fixed a bug that prevented the SWI budget terms from being written when the COMPACT BUDGET was used. GWF2MNW27 -- a number of problems were fixed as described in readme_MNW2.txt. GWF2LAK -- Corrected a bug in which an incorrect cell number was calculated and written for the COMPACT BUDGET option. Fixed array allocation error. GWF2DRT7 -- When a return cell went dry, the program failed to write a budget record for the COMPACT BUDGET option. This resulted in an incorrect number of records. Program was modified so that a zero value is written to the budget file for a return cell if it is inactive. GWF2SFR7, GWF2LAK7, GWF2UZF1 -- See file LAK_SFR_UZF_updates_MF2005.txt for a description of changes. LMT8 -- Updated the LMT package from 7 to 8. LMT8 writes the flow file required by MT3D-USGS. GMG -- The GMG solver was not designed to be compiled for 64-bit computers. The solver would work when compiled for 64-bit machines, but encountered errors for large problems. The GMG code was modified to work for large problems on 64-bit computers. UTL7 -- Corrected a programming error for logical value comparison. ULSTRD will now accept upper and lowercase (BINARY) for FMTIN. Added new capability to use an auxiliary variable as a multiplier for ULSTRD. If an auxiliary variable with the name AUXSFAC is detected, then ULSTRD will multiply the conductance column (or other column that is scaled with SFAC) by the values in the AUXSFAC column. If SFAC is also specified, then the conductance column will be multiplied by SFAC and the values in the AUXSFAC column. Removed the mnw1to2 source and run files. Minor spelling errors were corrected in many of the source files. Most of the errors are within code comments, but some pertain to text strings written to the listing file. Many of these errors have been present since the first release. MODFLOW-2005 runtime executables included in this distribution are released for the 64-bit version of the Windows operating system. o Version 1.11.0 08/08/2013 GWF2SWI27 -- This is the Seawater Intrusion (SWI2) Package, which has been added. GWF2STR7 -- Added free format input option, which is used when the BAS Package FREE option is specified. UTL7 -- The ULSTRD list reading utility subroutine was modified to allow lists to be read from binary files. See file the revised ULSTRD input instructions in file RevisedMF2005Input.pdf . GWF2WEL7 -- WEL Package is no longer deactivated when there are 0 wells. PCGN -- Removed non-standard KIND statements. o Version 1.10.0 03/06/2013 OBS2BAS7, OBS2CHD7, OBS2DRN7, OBS2GHB7, OBS2RIV7, OBS2STR7 -- Added NOPRINT option to turn off the output of data in the Listing File. See the input instructions in OBS.pdf . GWF2MNW27 -- a number of problems were fixed as described in readme_MNW2.txt . PCGN2 -- Corrected logic error that resulted in excessive inner interations in the first outer iteration of a time step. This correction reduces execution time. GWF2BAS7 -- In the Name File for DATA and DATA(BINARY) files, the "OLD" option indicates that the file must already exist; however, the file was previously opened with the READWRITE action specifier. A modification has been made so that such files are opened with the READ action specifier, which allows other programs to read the files while MODFLOW is running. GWF2DRT7 -- Modified the open statement for OPEN/CLOSE files to specify that these files are opened for READ access rather than the defult READWRITE access. GWF2SFR7, GWF2LAK7, GWF2UZF1, GWF2GAG7 -- See file LAK_SFR_UZF_updates_MF2005.txt for a description of changes. o Version 1.9.01 05/01/2012 GWF2BAS7 -- Fixed bug that caused MODFLOW to incorrectly continue execution when solver closure criteria are not met and the percent budget error is negative. The bug occurred even when the new STOPERROR option was not being used. o Version 1.9.0 03/30/2012 GWF2BAS7 -- Added an option, STOPERROR, to specify a budget criterion that allows a simulation to continue running even if the solver closure criteria are not met. "STOPERROR" is an optional keyword that can be specified in the options list (input item 1) of the Basic (BAS) Package input file. The real number, STOPER, must follow the keyword. STOPER is a percent discrepancy that is compared to the budget percent discrepancy when the solver convergence criteria are not met. Execution will continue unless the budget percent discrepancy is greater than STOPER. Added information in the listing file about the precision of variables. This shows whether the code was compiled used mixed double and single precision or full double precision. Increased the number of digits used for printing the number of time steps in some format statements. Increased the number of digits used for printing the time step from 3 to 5 in several places. GWF2STR7 -- Added support for compact budget and auxiliary data. For example, this allows the specification of IFACE for use with MODPATH. The auxiliary data are defined as in the other packages, such as the RIV Package, that allow auxiliary data. GWF2FHB7 -- Added the functionality to write the FHB IAUX input variable for flow boundaries into the budget file as the MODPATH IFACE variable. This happens automatically if COMPACT BUDGET AUXILIARY is specified in the Output Control file. GWF2LPF7 -- Added an option to turn off the checking that a value is defined for all cells when parameters are used to define layer data. This option is implemented by specifying the keyword "NOPARCHECK" as one of the options in input Item 1 of the LPF input file. GWF2SFR7 -- A number of changes were made, including some new options. The changes, including modified input instructions, are described in file LAK_SFR_UZF_updates_MF2005.txt. Input files for the prior release 1.8 of MODFLOW-2005 continue to work. Consolidated SFR input instructions are included in file: Updated_SFR2_input_instructions_MF2005.pdf . GWF2LAK7 -- A number of changes were made, including a new option to specify lake bathymetry data through external files. The changes, including modified input instructions, are described in file LAK_SFR_UZF_updates_MF2005.txt. Input files for the prior release 1.8 of MODFLOW-2005 continue to work. GWF2UZF7 -- A number of changes were made, including some new options. The changes, including modified input instructions, are described in file LAK_SFR_UZF_updates_MF2005.txt. Input files for the prior release 1.8 of MODFLOW-2005 continue to work. PCGN2 -- Added the PCGN solver. GWF2MNW27 -- A bug was fixed that affected simulations when both MNW2 and the HUF Package were used in the same simulation in conjunction with the partial penetration correction. The variable KY is now declared as a Double Precision variable instead of being implicitly assumed (incorrectly) to be an Integer variable. A number of minor changes were made in Format statements to produce a cleaner output file. In Subroutines GWF2MNW27BCF and GWF2MNW27HUF, corrections were made to assure the correct check is made for steady-state or transient conditions and to prevent a divide by zero error if a cell is dry. A bug was fixed for the calculation of angles theta and omega for slanted wells with an orientation into the southwest directional quadrant. Fixed a bug that caused erroneous values to be written to the compact budget file (specifically, for inactive MNW wells), although the numerical solution was accurate, as were the budget numbers written in the main listing file. LMT7 -- Updated the code to support MNW2. Data handling was updated to support use in the Local Grid Refinement (LGR) version of MODFLOW. The input file is unchanged GWF2GHB7 -- Fixed bug that prevented NO PRINT option from working. OBS2BAS7 -- Fixed a problem with multi-layer head observations. Observations involving an interpolation to a single neighboring cell were incorrectly eliminated. GMG7 -- Fixed a problem that caused MODFLOW to abort in some rare conditions. SIP7 -- Modified SIP to avoid failure in the unusual situation that head change is 0 at all cells for an iteration. PCG7 -- Fixed a memory access error when the polynomial preconditioner is used. Added IHCOFADD option. When an active cell is surrounded by dry cells, the cell normally converts to dry. The new option causes the cell to convert to dry only if storage and head-dependent boundary flow are also 0. IHCOFADD is a 4th integer input item read on the first input line. A non-zero value activates the option. An unspecified or 0 value turns the option off. DE47 -- Modified code to allow a solution to occur for a single-cell model. GWF2SUB7 -- Fixed an uninitialized variable that caused MODFLOW to abort in some situations. GWF2HUF7 -- Fixed a bug that caused flow across some cell faces to be incorrectly saved in the budget file, which affected Modpath. Fixed A bug that caused an array to go out of bounds in some situations. Fixed a bug that caused excessive time to be spent substituting parameter values for arrays. o Version 1.8.0 12/18/2009 Added MNW2 Package. This is an alternative to the original MNW Package, which is referred to as MNW1. MNW1 remains in MODFLOW-2005, but both packages cannot be used in the same simulation. GWF2SFR7 -- Runoff generated by the UZF Package was not being added to the assigned stream reaches within the Formulate routine of the SFR2 Package; however, this runoff was being added to stream reaches within the Budget routine, which caused mass balance errors. The bug has been corrected. GWF2UZF1 -- Fixed a problem in which UZF was obtaining 0 for the vertical K when the top layer is inactive. UZF will now obtain vertical K from the uppermost active layer. GWF2LAK7 -- Two minor bugs were corrected -- see readme_LAK.pdf. o Version 1.7.0 9/23/2009 GWF2BAS7 -- Added MXITER to the GLOBAL Module so that a different value can be used for each grid when using Local-Grid Refinement (LGR). This change has no impact if LGR is not being used. Added observations from the Streamflow-Routing Package (STR) to the Observation Process. GWF2ETS7 -- Added option (NESTOP=3) to cause ET to be applied to the uppermost active cell in each horizontal location. GWF2SFR7 -- A bug was fixed that caused the model to fail to converge or to produce erroneous results in simulations with transient streamflow routing when the ICALC=3 option was used. Another bug was found in the calculations of mid-point flow, which is printed to the gage output. This erroneous streamflow calculation did not affect anything other than the printed streamflow at the mid-point of a stream reach to the gage file. See file readme_SFR.pdf in the doc\Updates directory for the full history of SFR changes and information about updated SFR input instructions. GWF2UZF1.f -- A bug was fixed that affected the value of the UZF input variable VKS. The error occurred if the vertical hydraulic conductivity for UZF was specified in the LPF input file and if the LPF input variable LAYVKA was not set to 0, such that the LPF input variable VKA is the ratio of horizontal to vertical hydraulic conductivity. A bug was fixed in which UZF was not allowing recharge and discharge to be simulated for dry lake cells when the LAK Package was being used. Another bug was fixed that, in some cases, caused water content profiles to be incorrectly printed in separate files. This bug did not affect simulation results. Finally, the options for writing unsaturated flow budget files were changed. See file readme_UZF.pdf in the doc\Updates directory for the full history of UZF changes. GWF2LAK7.f -- To allow the user to better assess the reliability of the lake calculations, time-step and cumulative mass-balance errors (as percent discrepancy) are calculated for each lake and have been added to the lake budget output information in the main listing file and to the gage output file for a lake. The Lake Package was also modified to always write IFACE values when saving data to a compact budget file. This will facilitate enhanced compatibility and consistency with MODPATH. Modifications were made to the code to better evaluate the lake volume and changes to lake volume for each time step and to allow the lake to drain and fill on the basis of surface water and groundwater inflows and outflows. See file readme_LAK.pdf in the doc\Updates directory for the full history of LAK changes. GWF2GAG7.f -- Two new output options have been added to the Stream and Lake Gaging (GAGE) Package. An option has been added for Stream output to list selected budget components summed over all stream reaches when unsaturated flow is simulated (OUTTYPE = 8) and an option has been added for Lake output to print volumetric flow rates at a Lake gage (OUTTYPE = 4). See file Gage7_input_instructions.pdf in the doc\Updates directory for complete descriptions of the options. o Version 1.6.02 6/5/2009 OBS2BAS7 -- Fixed a bug that incorrectly caused some multi-layer head observations to be eliminated because dry cells were being checked in the wrong layer. HUF2 -- Fixed a bug that sometimes caused the interpolated head in hydrogeologic units to be incorrectly calculated. OBS2 -- Additional digits included in the output of simulated equivalents. GWF2BAS7 -- Increased maximum number of clusters and instances for defining parameters. o Version 1.6.01 3/4/2009 GWF2SFR7 -- Fixed the problem in which the new NUMTIM and WEIGHT variables that are read when using the transient routing option (IRTFLG>0) were ignored. Also added the FLWTOL variable, which is documented in the readme_SFR.txt file. o Version 1.6.00 1/23/2009 GWF2BAS7 -- Changed the message printed when the solver does not meet convergence criteria. Old message: "FAILED TO CONVERGE ...". New message: "FAILED TO MEET SOLVER CONVERGENCE CRITERIA ...". The maximum number of parameters has been increased from 999 to 2000. Main program -- Fixed bug that caused numerical error messages from SIP, PCG, and DE4 solvers to print multiple times. PCG7 -- Added statement to write locations of isolated cells that are converted to no flow. The code was modified to set DAMPPCG to 1.0 if the user specifies it as 0.0. Similarly, DAMPPCGT is set to 1.0 if the user specifies it as 0.0 GWF2SWT7 and GWF2SUB7 -- Fixed the problem in which a divide-by-zero error occurred when these packages were used with a steady-state stress period with PERLEN specified as 0.0 . GWF2HUF7 -- Fixed bug in which error messages identifying problems with vertical conductance calculations specified reversed row and column indices. A bug was fixed to allow proper calculation of SC1. Previously, the method of computing SC1 allowed the portion of an HGU that is above the topmost active cell or below the bottommost active cell to be included in the HGU thickness within those cells. GWF2SFR7 -- Added a check for values of streambed thickness that are zero. Removed duplicate declaration of variables NHUF and HGUVANI. Added definitions of NUMTIM and WEIGHT to the readme_SFR.txt file. GWF2LAK7 -- Reactivated the capability to use LAK with the HUF PAckage. GWF2UZF1 -- Removed duplicate declaration of LAYTYP. GMG7 -- Fixed bug that caused a file unit error when IADAMPGMG was 1 or 2. Added HYDMOD -- This saves data for producing hydrographs. Added LMT7 -- This is the link to the MT3DMS transport code. OBS2BAS7 -- Fixed a bug that caused incorrect values for multi-layer head oservations. Incorrect weights were being used in some situations. GWF2BCF7 -- Fixed problem in which input items 1 and 2 were read with free format even when fixed format was specified. GWF2LPF7 -- Added the NOVFC option, which turns off the vertical flow correction under dewatered conditions. This option turns off the vertical flow calculation described on p. 5-8 of USGS Techniques and Methods Report 6-A16 and the vertical conductance correction described on p. 5-18 of that report. To activate the NOVFC option, use the keyword NOVFC as the Options Variable at the end of Item 1 in the LPF Package input file (see Options variable on pages 8-28 and 8-29 of TM 6-A16). o Version 1.5.00 4/28/2008 PCG7 -- Added capability to use different damping factors for transient and steady-state stress periods. See readme_PCG.txt. GWF2LPF7, GWF2BCF7, GWF2HUF7 -- Set HNEW=HNOFLO when a cell initially has all transmissive terms as 0 rather than setting HNEW=888.88 . GWF2BAS7 -- Added variable HDRY to module GWFBASMODULE. The LPF, BCF, HUF, MNW, UZF, and SFR Packages were modified to access HDRY through GWFBASMODULE. Added the ability to change the reference time step when computing drawdown, which was also an option in MODFLOW-2000. This is done through the Output Control option. For each time step for which output is desired, "DDREFERENCE" can be optionally specified at the end of any "PERIOD n STEP n" line, and indicates that the heads calculated at the end of the associated stress period and time step are to be used as the reference heads for calculating drawdown for all subsequent time steps up to the next occurrence of DDREFERENCE. By default, the initial heads will be used for calculating drawdown. For example, if the user specifies the following input line: PERIOD 2 STEP 1 DDREFERENCE then heads calculated at the end of time step 1 in stress period 2 will be used as the reference heads for calculating drawdown until DDREFERENCE occurs in another "PERIOD n STEP n" line. GWF2GAG7 -- Removed duplicate reference to variable RNF in the USE GWFLAKMODULE statement in SGWF2GAG7LO. OBS2BAS7 -- Fixed a problem where a head observation was incorrectly omitted when some of the neighboring cells used in the horizontal spatial interpolation were dry. GWF2SFR7FM -- Fixed precision problem that caused convergence problems for steady-state time steps. Updated to the version used in GSFLOW. See readme_SFR.txt. GWF2LAK7 and GWF2UZF1 -- Updated to the version used in GSFLOW. UZF has a small change in input data. See readme_LAK.txt and readme_UZF.pdf. GWF2CHD7, GWF2GHB7, GWF2RIV7, GWF2DRN7 -- Fixed bug that caused the program to stop when the NOPRINT option is used with parameters. GWF2HUF7 -- A bug was fixed to allow proper handling of SY parameters. HUF was also modified to calculate vertical hydraulic conductivity and specific yield for all cells in the uppermost cells at the beginning of the simulation as required for use with UZF. See readme_HUF.txt. o Version 1.4.00 11/02/2007 Added SUB-WT Package GMG -- Added adaptive damping option as documented in "GMG_Damping.pdf" and "Banta_damping_paper.pdf" in the doc directory. GWF2LAK7 -- Corrected precision declaration for functions FINTERP, DERIVTERP, and OUTFLWTERP. o Version 1.3.01 GWF2BAS7 -- MXPAR, the maximum number of parameters, increased from 500 to 999. o Version 1.3 GWF2GAG7 -- Removed duplicate reference to RNF in USE statement in subroutine SGWF2GAG7LO. Modifications to format statements. GWF2UZF1 -- Fixed memory allocation problem when using UZF to simulate discharge to land surface while not simulating unsaturated flow. The calculation was changed for simulating head-dependent recharge and discharge when the ground-water head is near or above land surface. GWF2SFR7 -- Fixed logic for reading mixed parameter and nonparameter input data. GWF2SFR7 -- Fixed problem where FLOWC was uninitialized when ICALC=0. Added ability for SFR to be used with HUF. GWF2RCH7, GWF2EVT7, GWF2ETS7 -- Added a check to not use the layer indicator value if the indicator value is 0. OBS2BAS7 -- Changed format for saving observations in a disk file to write less digits.. OBS2BAS7 -- Fixed problem with head-change observations at cells that have an initally dry simulated value, but values at later time are wet. The later values were being computed based on the dry value, and now all of the values at later times will be dry. o Version 1.2.01 10/24/2006 GWF2SFR7 -- A bug was discovered in SFR7 when NSTRM is positive or when NSTRM is negative and ISFROPT is 0. The error occurs because record 6 is not read after the first stress period. This causes the read sequence following stress period 2 to be incorrect. Many different problems can occur due to this bug, including stopping of the model. o Version 1.2 10/16/2006 Added SFR, LAK, UZF, and GAG Packages GWF2MNW7 -- Converted PLOSS to double precision DE47 -- Added missing arguments in the call from MAIN to DE47AP KDEP capability in GWF2HUF2 -- Corrected memory allocation for GS array when IFKDEP is 0. GWF2DRT7 -- A bug that caused a budget error when a drain-return cell is inactive has been fixed. Now, if the return cell is inactive (IBOUND=0) or constant-head (IBOUND<0), no return flow takes place, and all drain flow exits the model. Also a bug that caused an error reading non-parameter data was fixed. GWF2SUB7 -- Modified to allow comment lines to be inserted into the SUB input file anywhere except where arrays are to be read by one of the array-reader subroutines (U2DREL or U2DINT). Note to users of the Hydraulic-Conductivity Depth-Dependence (KDEP) capability: The memory allocation error for the GS array exists in the KDEP code beginning with its first release in version 1.12 of MODFLOW-2000 (MF2K) and continuing through version 1.15 of MF2K. The error was fixed beginning with version 1.16. The error also occurs in versions 1.0 and 1.1 of MODFLOW-2005. The error has been found to cause problems in some (but not all) models that specify input variable IFKDEP equal to 0. Variable IFKDEP is a flag indicating the source of the array specifying reference-surface elevations used for the depth-dependent hydraulic-conductivity calculations. When IFKDEP = 0, the TOP array specified in the Discretization Package Input File is used; when IFKDEP = 1, the array is specified in the KDEP input file (variable RS). In some circumstances, specification of IFKDEP = 0 led to inadequate allocation of memory for the reference surface. The error could cause errors in some of the budget calculations. Models that specify IFKDEP = 1 should not be affected by this error. If users are uncertain whether their simulations using KDEP are affected by this error, they are encouraged to run their data sets with MF2K version 1.16 (or higher) or MODFLOW-2005 version 1.2 (or higher) and compare the new results with those of the earlier version. o Version 1.1 05/18/2006 SGWF2LPF7DA -- Corrected deallocation statements for several variables hufutl7.f -- Removed some unused code De47.f -- Moved several variables into DE4MODULE to support Local Grid Refinement (LGR) GWF2BAS7AR -- added MFVNAM as an argument to allow different versions of MODFLOW to print a different version name -- e.g. MODFLOW-LGR as opposed to MODFLOW-2005. Added DRT, ETS, RES, and SUB packages Added Observation (OBS) Process GWF2MNW7RP -- Corrected HDRY value when HUF is used -- Fixed initialization problem with variable ICMN. GWF2MNW7 -- Added an 18th element to the WELL2 list to store a well identifier GWF2STR7 -- Increased the number of digits for output of streamflow terms in the Listing File. o Version 1.00 01/15/2006: This version is the initial release.