September 23,

CE-QUAL-W2

February 29, 2024: Thanks to Cory McDonald at Hydros for pointing out an issue with the partial pressure of CO2 gas calculation prior to 1980. The computation after 1980 was fine, but prior to 1980 there was an integer overflow that made the computed value incorrect. This has been updated with this new release. That is the only update in this new code update.

January 26, 2024: We have released a beta version of Version 5. This release includes a new Hg model and more in-depth selective withdrawal algorithms for complex or multiple outlets. There are a few items that are still needed such as a model preprocessor, a revised V5 user manual (documentation on the 2 new algorithms is provided). The Existing V4.5 User Manual is still valid for this release. We are currently testing the model and may make minor changes in the main control file. We also expect a couple more code enhancements – writing out to HDF5 file format and code that stores the hydrodynamic results so that one can quickly iterate on water quality. Dr. Zhong Zhang has been instrumental in getting this update together with help from Dr. Chris Berger.

January 18, 2024: Updated code with new w2 model and preprocessor executables and updated User manuals have been published. See Part 5 of the User Manual for a detailed list of enhancements and fixes.

January 15, 2024: There are a host of small fixes coming in the next update which will be posted by the end of the month. One of the enhancements is the ability to for the user to choose meteorological files by waterbody or by a segment number range. This allows a model user to use one waterbody for a dendritic reservoir but use different meteorological files for different segments. Also, the user can now set the vertical mixing when there is a vertical density instability. This occurs routinely as water cools and sinks in a water body. The mixing coefficient (vertical turbulent diffusion) was set internally to 1000 m2/s which sometimes can cause too aggressive mixing. More details will be posted when the new code is posted. Also, we will be posting a beta version of CE-QUAL-W2 Version 5 which will have the Hg model and more advanced outlet modeling.

September 26, 2023: Updated a few example problems that had preprocessor errors because the Excel tabs – correct in the xslm file – had not been exported to a comma delimited file. The examples all have no errors now.

September 18, 2023: See part 5 of the User’s manual on pp. 36-37 for a full list. There were several enhancements: Added another output file for sediment transfer velocity to the sediment diagenesis output, improved spreadsheet output with better output precision, added another output variable to the W2ErrorDump file, added 2 new output variables (velocity and horizontal flow per layer) and improved the output in SPR files, and added more ports (was set to a maximum of 11) to the auto-port selection. Other updates include fixing a parameter in the BACTERIA water quality section, fixing the file directory specification for WDO files, adding Branch Active/Inactive to SNP files, and some code updates suggested by Stewart Rounds in several routines to improve the robustness of the code. Also, the density of water was computed based on a minimum of 0^oC. Before this update, the model could compute water temperatures below freezing and compute a density that was based on that temperature. This accidentally created very light and cold water that did not mix with water below it.

July 14, 2023: Another small fix on the W2Anim output.

July 13, 2023: There was a small bug fix for W2Anim output file in case the user used nested directories that was uploaded.

July 4, 2023: The new update posted today includes a few bug fixes for restart to work, a new output file for the post-processor W2Anim from Stewart Rounds, added functionality for gates to have variable flow and centerline elevation, and added functionality to have CUF be more precise in terms of updating the constituent kinetics. The User manuals and preprocessor were updated also.

February 11, 2023: New update posted includes the following: (1) Complete revision of Fe and Mn sediment diagenesis model, (2) sediment diagenesis temperature in aerobic and anaerobic layers can be computed or use the adjacent water temperature, (3) bug fixes in sediment diagenesis (time step skipping based on hydrodynamic time step) and some other minor fixes, (4) a new option to output the reservoir dissolved oxygen volume less than 1 mg/l over time, (5) preprocessor updates include several new checks, (6) updated User Manual, and (7) updated example problems with the new templates for sediment diagenesis and habitat.

February 7, 2023: We have several updates coming in the next update: (1) Complete revision of Fe and Mn sediment diagenesis model, (2) additional options for sediment diagenesis temperature in aerobic and anaerobic layers, (3) User Manual, preprocessor, and W2 code minor input/output fixes. A complete list and the revised code will be posted by the end of February.

November 14, 2022: There are several bug fixes and enhancements in this update. These include: (1) The w2_post post-processor can now display all derived variables such as chlorophyll a, pH, TOC, TP, TN, and others as defined in the model set-up. Prior to this update the model user could only display the active state variables. (2) The pre.opt file from the preprocessor had an output error on the water balance corrected. (3) The Environmental performance feature can now be applied yearly for multiple year simulations or for a discrete time period. (4) A PARTP bug was fixed for the partitioning of P onto inorganic SS. This may mean that the model user who calibrated using the old code may need to re-examine the value of PARTP to get the same result as before. (5) A bug in the time step for sediment diagenesis was fixed. Prior to Version 4.5 sediment diagenesis was evaluated at every time step. It did not use the CUF feature where the water quality kinetics can be updated as a multiple of the time step. This was valid since the hydrodynamic time step was often small and the kinetics did not need to be calculated at that same frequency. This was applied to sediment diagenesis in Version 4.5 to save computational time. (6) Minor fixes to flux output and tsr output. These are listed in Part 5 of the User Manual. We are working on several new features: updated to the selective withdrawal algorithms for multiple withdrawals, running and saving hydrodynamics so that one can run the model quickly to get close to water quality calibration before integrating water quality and hydrodynamics, Hg modeling, and several other fixes/updates, including the mixing criteria when there is a detected density instability in the model.

August 5, 2022: The earlier upload forgot to include the new executable for the W2 model even though it had the updated source code. This has just been updated. Also, the w2_post post-processor will be updated in the next version to allow for plotting derived as well as state variables.

July 21, 2022: Just uploaded a new code with a couple of minor code fixes in water quality found by Cory McDonald (many kudos!!). These affected the sediment release of a generic constituent based on zero order SOD. This was a new feature in Version 4.5. Also, in the MnII routine, the FeII reduction rate was accidentally used rather than the MnII reduction rate. These have been fixed. Thanks again Cory!

July 20, 2022: The code and User Manuals were updated. The code fixes include fixes for using the constriction feature between model segments, fixes for CH4 generation and H2S generation from the sediment diagenesis model, updates to the preprocessor and pre.opt output, an enhancement for DO added to turbine flows, added an option in sediment diagenesis for variable fraction of incoming labile/refractory organics, and some minor fixes for restart and the specification of ONH during restart. This is a minor update. But if you are using the sediment diagenesis model, you should be using this update. We are working with Dr. Zhong on the Hg model and debugging it on the Snake River system currently. This fall also we will be working on enhancements to the withdrawal envelope calculations for complex outlets and the option for decoupling water quality from hydrodynamics for quicker water quality calibration.

December 20, 2021: Updated the water balance utilities (GUI and Console versions) with a couple of code fixes.

December 18, 2021: There were several minor updates to Version 4.5 that include bug fixes for the converter utility, updates to the user manuals, addition of all the example problems updated to 4.5, more preprocessor checks, more output files for the sediment diagenesis model to examine porewater predictions of nutrients, and a fix for reading in organic matter as C. We are also working on some new additions for organic matter and an upcoming Hg model formulation.

August 30, 2021: There is an update to the Version 4.5 model that has minor fixes for the converter utility and a critical fix for sediment diagenesis temperature prediction. Part 3 of the User Manual for sediment diagenesis has also been updated showing that there are new output files for sediment temperatures for the aerobic and anaerobic layers and how to control sediment temperature using model coefficients TSED, CBHE, and the pore water temperature diffusion coefficient.

July 26, 2021: We have just released Version 4.5. We have migrated all our own applications to Version 4.5 and have done extensive testing. There are numerous enhancements and updates shown in the W2 history tab. All User manuals are updated to the new version. We have 2 examples in the examples folder, but more will be added soon with the updated control file. Let us know if you find any quirks in the updated code.

February 17, 2021: Posted a minor update to the converter utility that cascaded through the preprocessor and W2 executable when using the Excel macro control file. We are still working on a large update that will be posted within a month as a research code version. More details as we get done testing it.

November 27, 2020: Posted a minor update to the converter utility - bug fix when NTR=9 (thanks to Prof. Dr. Ali Erturk for tracking this down!) and several formatting improvements.

October 8, 2020: Posted a minor update to V4.22 that fixes writing out a spreadsheet file with SPRC=ONV for the case of the csv control file. Also a couple user manuals had some minor updates.

September 16,2020: Posted a couple minor updates to the User Manual in the latest 4.2.2 download. Parts 1, 2, and 3. No code updates.

September 3, 2020: Fixed a bug in the update of PCO2 for multiple years. The earlier code worked fine until you went into the 2nd year. Now all is cool!

August 27, 2020: Updated the User Manual part 2 under TIC and fixed a bug in the Converter utility from w2_con.npt to an Excel file in case there were more than 1 Withdrawal.

August 18, 2020: We have released Version 4.2.2 which has only one important update for TIC and pH. If you are modeling pH, you should be upgrading to this version. There are 2 new variables in the control file that control atmospheric CO2 calculations and allow the user to either set CO2 atmospheric in ppm or to use a regression equation from NOAA for global average CO2. The earlier model had an equation for PCO2 based on data from 1960. See the updated User Manual sections, especially Part 2 under TIC describing the new equations for computing Henry's Law temeprature dependence and determining the partial pressure of CO2 in the atmosphere. We have many other items we are working on including making all auxilary input files as part of an Excel master worksheet with easy input/output. Also, all the example problems, the user-manual, the control-file converter to Excel, and preprocessor were all updated. Stay tuned.

July 21, 2020: We added the 64-bit Executable to the download package since Intel updated their compiler and fixed the bug in dialog boxes for 64-bit code. We are also working with Dr. Zhang to bring many new updates to the W2 model. Some of these include pulling out ‘generic variables’ from the sediment diagenesis code such as CH4, H2S, Fe, Mn, N2, bacteria, and others as discrete state variables (thus eliminating confusion in setting these up), converting all of the auxiliary control files (like w2_selective.npt, w2_habitat.npt, etc.) to csv files (and tabs in a spreadsheet for example), adding atmospheric deposition explicitly as a mass loading (prior to this one could use the distributed tributary with a Q X C that equals the load but with a minimal flow – but this was painful), addition of Hg algorithms for the water column and sediment based on a study with Idaho Power on the Hells Canyon complex, and development and release of post-processing tools in R, MatLab and Python. Stay tuned.

June 24, 2020: We are releasing Version 4.2.1. This has had many updates (See History or User Manual Part 1) that should prove to be very useful. One that will be used by many will be the new Excel input file that combines the w2_con.npt and graph.npt files. This allows for easy filling in blanks, lots of explanations and simplified file setup. Please let us know if you are an Excel guru how that could be improved further. Also, the new preprocessor will make it easier to see the errors since one does not need to open the pre.err file to see the list of errors. There have been many preprocessor updates under the hood in terms of checking model input files and model coefficients. The User Manuals also have had hundreds and hundreds of updates. The section on the new Excel version of the control file is short and since it generally follows the order in w2_con.npt, a full rewrite of Part 3 with the Excel version has not yet been done, but it is on the tracker. We have only released the 32-bit executable for w2 since the 64-bit still is waiting for an Intel compiler update. All the code survived the workshop we just completed and we made final updates afterwards to clarify and improve different aspects of the model. We also have a converter utility to convert legacy files to the new Excel format. There is a how-to explanation in Part 5 of the User Manual.

April 16, 2020: Amid the COVID-19 pandemic, a new version of CE-QUAL-W2 will soon be available. This will be termed Version 4.21 and it incorporates several new features: a new Excel based control file (graph.npt file no longer needed, easy and clear control file), an update to the Multiple waterbody enhancement from Stewart Rounds at USGS, enhancements for the pump algorithm, the preprocessor, and output file formats (W2ErrorDump.opt, w2.wrn). In addition, there have been many updates in the User Manual. We are awaiting a bug fix for the latest Intel compiler for 64-bit code. The 32-bit compiler works, but the 64 bit one has a bug. Once this is updated by Intel, we will post this new version.

November 15, 2019: Today’s new code post has several minor bug fixes as noted in Part 5 of the User Manual. These fixes are primarily related to fixing instabilities in the pipe algorithm and fixing a bug in the sediment diagenesis turbidity algorithm. Upcoming updates include: moving turbidity to a derived variable (it is currently enmeshed in the sediment diagenesis model), releasing a new control file that can be edited in Excel and eliminating the graph.npt file, and finalizing/releasing our research code on cynaobacteria vertical migration.

November 11, 2019: FYI: Yoav Bernstein has posted a CE-QUAL-W2 bathymetry editor using open-sources QGIS at https://github.com/WQDSS/qgis-cequalw2-bath and has been working on another GitHub project [https://github.com/WQDSS/Evaluna] that runs alternatives of model simulations that he is still refining.

September 20, 2019: A new model release has been posted – Version 4.2. This includes a significantly updated User Manual – that will allow for easier updates since it is now in 5 separate parts. There are many new enhancements for Version 4.2: (1) Multiple waterbody simulation on multiple cores (“dynamic loading”), (2) SYSTDG algorithm for TDG from hydropower spillways, (3) new User Manual, and (4) numerous updates (such as changes to epiphyton burial calculation, auto port selection splitting new file input, significant revisions to sediment diagenesis files, ability to specify which branches to output for Tecplot contour output, more output files changed from fixed text output to comma delimited format). Also, the model release notes are no longer a separate file but are now part of the User Manual Part 5 in case you check those from time-to-time.

April 16, 2019: We have been working on a lot of new updates for the model – some of these include bug fixes for scour in the sediment diagenesis model (many thanks to Lindsay Bearup at the USBR!) and enhancements for running multiple waterbodies in series (reservoirs and river sections) on multiple processors. Our preliminary results show speed ups from a modest 20% to an incredible 90% for long-running systems. I also decided to re-organize and rewrite the User Manual so that it can be easily read, provides better explanations of theory, and provides more information on example problems. Parts of this new manual should be coming out this summer. Also, Yoav Bornstein is producing a QGIS (open source GIS) tool for developing grids for CE-QUAL-W2. He should be demonstrating it this summer for our annual CE-QUAL-W2 workshop June 17-21 in Portland.

December 19, 2018: This bug fix update includes the following fixes: (1) SPR output volume weighted output fix, (2) Volume, energy and constituent mass balance fixes, and (3) fix on internal computation of solar radiation. If you track energy and mass balances, there were some situations where the energy balance and mass balance were not showing to machine precision as was the volume balance – even though the model results were fine. This has been fixed for several anomalies. Also, if you use the internal short wave solar algorithm and have a long simulation (> 10 years) or use a reference year far from the start date – this will impact your model computed short wave solar radiation by not predicting the winter solstice and summer solstice correctly. Many thanks to Dan Turner and Stewart Rounds for finding that one!

December 10,2018: This latest update includes several bug fixes for flux output to the TSR file (unit correction), Spreadsheet output for volume averages, and updates to the User Manual. One enhancement was added for particle tracking – setting an observation point and recording when particles pass a given location.

September 27, 2018: A new code has been added that computes vertical volume weighted averages for the SPR file (as was done earlier for the longitudinal profile file). Some of the blog entries are missing below between April and September because of a restoration of the web site with back up files. There have been several updates since April that are outlined in the W2 release notes such as enhancements to the particle tracking and constrictions between model segments, as well as assorted refinements and bug fixes.

April 11, 2018: An updated version of Version 4.1 has been released that includes many fixes and embellishments as noted in the Release Notes. These include: (1) an updated W2 Control GUI Version 4 including many of the special features added since Version 3.7 (Note that the W2Tools version is still using the Version 3.7 W2 Control), (2) many new preprocessor checks especially for NaN in input files (as more use Excel to prepare input files, formula errors can generate NaN, which is accepted as a proper input for a numeric input), (3) a new waterbalance console application that allows for batch file processing and has more user options than the windows version of the waterbalance utility, and assorted updates to the Withdrawal Output frequency (you can now specify 1 hour rather than the 0.0416666666… day which leads to round-off issues for long simulations). Still working on a couple items – the particle transport time history of temperature and water quality, an option to reduce the cross-sectional area between segments in case of a bridge or other obstruction rather than having a small segment of reduced size just for the constriction.

March 8, 2018: We have been working on a few model updates that will be rolling out soon that include a couple minor cosmetic bug fixes, updates to reading in pH, more embellishments on particle transport, and an updated W2 Control GUI – the independent one not included in W2Tools. We are also hoping for an updated W2Tools soon. Also, we finally have a work around for using W2Control GUI on a touch-screen laptop. USING THE GUI W2CONTROL FOR TOUCHSCREEN LAPTOPS AND MONITORS: The software, W2Control, is a GUI preprocessor for the W2 model. It works fine on non-touch enabled monitors. But for touch screen monitors, like many of the latest laptops, the opening “treeview” menu does not work because of a software incompatibility with VB6, the source code. W2Control can though be used on a touch screen laptop by doing the following: Go to Services by typing ‘Services’ in the command line or Cortana line. In the list choose ‘Touch keyboard and Handwriting Panel Service’. Right click your mouse and choose Properties and change ‘Automatic’ to ‘Disabled’. Then click STOP in the Service Status to stop the service. Click APPLY. The W2Control then works as expected.

December 10, 2017: There are a few minor bug fixes in this release dealing with TDG, pump output file naming, and kinetic flux output if multiple waterbodies (see Release Notes). Let me know if you have any questions/comments on this new update.

October, 3, 2017: We still have a few items to add to Version 4.1, but since it is file compatible with Version 4.0, I decided to release it in case one wanted to take advantage of some of the new features. Here is a list of the Version 4.1 new features: (1) Particle Tracking Algorithm. There is a new input file for activating the particle tracking algorithm, ‘parti-cle.csv’, and a new documentation report outlining how to use this new algorithm. (2) Branch active and inactive algorithm. In prior versions of the CE-QUAL-W2 model, if a branch lost water, the model would end. Now the model can activate or deactivate branches based on wetting and drying. Also, upstream inflows or tributaries are automatically added to the most downstream active segment of the in-active branch. This allows then filling and emptying a large reservoir with complex side branches with no further input of the model user. (3) Updates to the Sediment Diagenesis Model. These updates are focused on (i) increasing the speed of execution of the code, (ii) improved input/output including adding sediment diagenesis fluxes of P and N to the massbal.csv file for analyzing big picture nutrient balance of a waterbody, and (iii) Improved preprocessor checks of sediment diagenesis input parameters. (4) The value of Ax and Dx can now scale with the mean longitudinal velocity rather than being constants. (5) Canopy shade can be used in conjunction with the dynamic shade algorithm to estimate solar reduction when the channel has a vegetative canopy. (6) Assorted minor bug fixes and updates. [Thanks to Stewart Rounds, USGS, for suggesting several of these!] (7) Other changes still to be added to Version 4.1 include adding TDG and pH as input variables for in-flows/tributaries, vertical migration of algae, and further sediment diagenesis improvements. The fixes applied since the last Version 4.0 update are in the Version 4.1 release notes. The Updated User Manual for Version 4.1 has new sections on particle transport and descriptions on how to implement the new features mentioned above. Let me know if you have any questions/comments on this new update.

August 4, 2017: I expect by the beginning of September to release what we will call Version 4.1. Besides a host of small bug fixes (thanks to Stewart Rounds, USGS, for his help in finding more burrs in the saddle!) and small enhancements, this version will include the following new schemes: (1) particle tracking based on velocity and random motion tied to turbulent intensity, (2) branch active/inactive where wetting and drying can automatically add and subtract branches and take care of inflows and tributaries in the inactive branches, (3) an empirical method for estimating Dx and Ax or one can continue to use constant values, and (4) speed improvements in the sediment diagenesis model. This code will use the same input files as Version 4.0. There will be a new input file for the particle transport though.

April 17, 2017: This update includes improvements in the head boundary condition input file format for head, temperature and concentration (using csv files and simplified inputs when there is no stratification), fixing an error in the waterbalance utility and synching it with the updated tsr file format for Version 4, further updates to the User Manual, and a sprinkling of minor bug fixes affecting Tecplot output, tsr output, and the start/restart feature.

February 20, 2017: There have been a lot of accumulated enhancements and several bug fixes in this release. These include significant updates to the User Manual, fixed an old bug in Si dynamics, enhanced and updated the environmental performance model output, added more model file checks in the preprocessor, added derived variable output for Tecplot output (see CPL output). We are starting to work on the new control file (Excel csv file) and adding Stewart Rounds and Anette Sullivan's input of pH rather than TIC in tributary and inflows thus avoiding having to compute TIC from pH and Alkalinity data.

November 18, 2016: Updated the model code to the latest Fortran compiler from Intel and used the new command to auto-initialize all variables to zero (we still have some housekeeping on the sediment diagenesis model to do just that - so this saved us some time and users some grief perhaps). There are new enhancements to the preprocessor making it more powerful to debug a model application. Also, we changed the tsr file output getting rid of the 10 lines of comments and allowing the user to specify a filetype in the control file. Hence, if one specifies 'tsr.csv' in the file naming section of the control file, all tsr files will be written in csv format and are immediately accessible in Excel. In addition, there are updates/corrections to the User Manual.

June 11, 2016: Updated the sediment diagenesis model with a new variable initialization.

June 10, 2016: Updated the waterbalance utility so that it is compatible with the new output format of tsr files in Version 4. This utility now works with Version 4 and earlier versions.

June 7, 2016: The W2 Release Notes for Version 4 have been released. This includes a new section on how to run the model for the first time, tips on using batch processing, and using file names in subdirectories. The User Manual was updated to Rev6 with many minor updates and improved text. The preprocessor includes a few more model control file checks, and the W2 code restart function is now working properly with epiphyton and macrophytes and the new massbal.opt file. See the release notes for details of these updates. The CE-QUAL-W2 workshop is next week so we look forward to further in-depth testing to see if model users can ‘break’ or ‘stress-test’ the code.

April 19, 2016: Many updates have been made to the version 4 W2 Preprocessor, User Manual, model example problems, and W2 model executable. We are calling this Version 4.0. This means that from this point forward we will provide a set of User Notes for bug fixes and enhancements. The updates include: (1) Preprocessor: fixed the error check on the card line for TSR headers and made it compatible with User Manual, fixed initial concentration distributions printed in the pre.opt file for derived variables, added multiple checks for a comma delimited input file in case the model user forgot to use a ‘$’ character in the first position of the first line, added checks for the light extinction file (there were none before) in case it is included in the input set, and set up checks for the light extinction and gate file for comma delimited format; (2) User Manual: added updated information on dissolved oxygen sources/sinks (figure and source/sink term), revised text for older Fe-total state variable showing that using the new state variables for Fe and Mn is recommended, updated with new file features as mentioned in Model executable updates, and revised several other items of text to be synchronized with the latest code version, and re-added some figures that were causing a difficulty printing in pdf format; (3) Model Example Problems: added new Version 4 headers in all the model example programs control files, added text ‘V3.7/V4’ at the beginning of each control file to show that they are compatible with both programs, fixed several of the old example files that needed to be updated; and (4) Model executable: fixed a regression error with the new ice cover algorithm where ICEC=ON did not turn on the ICE calculations, fixed minor issues with alkalinity and macrophytes (having to do with the new initialization feature), added new csv input option for dynamic pump file, added new mass balance output file for nutrients N and P to assess sources and sinks of nutrients, added longitudinal profile plot output for easy graphing of longitudinal trends in rivers, added ability to have a floating skimmer weir, and updated several sections of code in the sediment diagenesis model including addressing comments from Dr. Nathan Wang of Golder Associates, Inc.

March 23, 2016: We have a large update coming that addresses many small issues and will add some enhancements to the Version 4 model, preprocessor, and User Manual. We are trying to resolve a couple minor issues before releasing the new updates. Expect these to be released around April 1.

November 2, 2015: Just posted latest Version 4 update with new features described below. The User Manual is now updated as is the preprocessor as well. With this release the feature set for Version 4.0 is complete and we will be calling it a beta version. This version is still file compatible with Version 3.7.

October 26, 2015: Several new enhancements to Version 4.0 continue to be made before we fix the # of enhancements for this Version #. These include: (1) TSR file output now includes the limiting nutrient term for algae growth for N, P, and light which is between 0 and 1, (2) Photodegradation (many thanks to Lillian Jeznak and John Tobiason at the University of Massachusetts in Amherst) and volatilization are now options for generic constituents, (3) N2 gas is now an option for a generic constituent. If this is used, the model automatically computes %TDG using both N2 and O2 state variables. (4) Ice melting and forming can be added to the water loss/gain in the model or not (this allows backwards compatibility to earlier model versions which did not add/subtract water during ice melt/formation). We expect to post this release which is still compatible with Version 3.71/3.72 later this week.

September 8, 2015: We continue to add enhancements and fixes to Version 4. These fixes/enhancements are (1) Fixed issue with reading in rainfall data in csv format, (2) Added new output features to tsr, cwo, dwo, two and qwo files - all in csv format (this eliminates problems with Julian day formatting and significant figures), (3) added capability of providing initial conditions for epiphyton and macrophytes using a vpr or a lpr file, (4) rewrite of ice formation and loss in order to conserve water mass in the ice, and (5) other minor updates including adding updates to The User Manual and preprocessor. There are still a few more items on our punch list including adding the capability of inputting rainfall accretion as a flow (like a distributed tributary) rather than in m/s dependent on the area of the lake at the time of the rainfall. The new files have been uploaded. This file version is still compatible with Version 3.72.

August 11, 2015: Updated the V4.0 code to fix a bug in ice formation/melt as it affects the water balance. Prior to V4, the model did not gain or lose water when ice was formed. Now, in V4, the model loses and gains water as ice forms and melts. Also, an updated User Manual for V4.0 with several new sections was added.

June 30, 2015: I have updated the W2 Version 4 package. It is now complete with many code updates, a draft User’s Manual, a new example program, and a working preprocessor. This version is file compatible with V3.71 and V3.72. Chris and I are still going to add a few more features to the V4 model and (unfortunately) ‘break’ the w2_con.npt file compatibility since there are too many items buried in the sediment diagenesis input file that need to be in the main control file. This of course means changes to the preprocessor and the GUIs. We have tested this new Version 4 on many applications and have not found any issues after numerous test cases. Of course, we are interested in others kicking the tires on this new release. Please let us know if you find some anomalous behavior.

May 21, 2015: We have posted a minor update for Version 3.72 (we have not updated Version 3.71 since users with Version 3.71 can use Version 3.72 without any model changes) that includes an issue with interpolating the wind speed for evaporation (see V3.72 Release Notes). Chris Berger and I are working on the Version 4 code after having carried all code updates into the new version. We are making some changes to the sediment diagenesis input files, adding preprocessor checks, and updating the User Manual. We are making version 4.0 file compatible with Version 3.72, in other words you can use 4.0 in any 3.71 or 3.72 model applications without any file changes. After some testing this next week, we should be posting a Version 4.0 Beta version prior to our workshop June 15-19 where we will be using Version 4.0.

April 9, 2015: A minor update to Version 3.71 was posted that just writes out a restart file (rso.opt) at the end of a simulation. This is useful for restarting the model after the run is over. Also, a new example has been added showing the Spokane River example with csv files as inputs. Version 3.72 was also posted today. Besides the new USGS auto-port selection algorithm, the User Manual has been updated including new explanations on the surface heat transfer formulae and 4 new examples for the USGS port selection algorithm. The only code piece that has not been updated is the preprocessor option for choosing the USGS algorithm if you use w2post (you can use a text editor to edit the w2_con.npt file or use the stand-alone GUI which has been updated for the USGS option for the auto-port selection algorithm). Other than specifying under ‘W2Selective’ ON or OFF, the new option is ‘USGS’. Other than this change in the control file, V3.72 is file compatible with V3.71.

March 13, 2015: Just posted an updated version of 3.71 with a couple enhancements and bug fixes. This is the last planned update to Version 3.71. I am currently working on Version 3.72, which includes a new auto port selection algorithm for blending release flows from reservoirs (the USGS code enhancements mentioned below). This should be debugged and ready to go by the end of March. We then expect an update to the Version 4.0 alpha (with the complete sediment diagenesis model) in April 2015 that includes all these prior updates to the Version 3.7 code.

February 2, 2015: An updated version of 4.0 alpha has been added with new example problems. We are still in the process of adding some features of automatic port selection to meet temperature targets from Stewart Rounds at USGS and a few other enhancements to complete the 4.0 package. This should be completed by mid-March. Also, the CE-QUAL-W2 workshop will be June 15-19 2015. Details can be found at http://www.pdx.edu/cee/QUAL-W2 . We expect to use exclusively the new 4.0 model code for the workshop.

November 24, 2014: We have posted the Version 4.0 alpha from the download page. This is CE-QUAL-W2 with new state variables and a sediment diagenesis model funded by CEMA, Canada. It is an alpha version since it will have several more planned enhancements, such as those described in the August 19 2014 update. Currently there is not a preprocessor for the Version 4 model preprocessor that checks all sediment diagenesis parameters, but that will also be released once we move to beta status. Please take Version 4 alpha out for a test drive and let us know if you have any questions on the new release.

August 19, 2014: We have been working with Stewart Rounds and Norm Buccola at USGS to use some of their port selection algorithms and pH algorithm. We expect to incorporate these into the next model release. Also, we received a green light from CEMA for releasing the full sediment diagenesis model. This will be released soon as a beta release with a draft user manual. It should be file compatible with Version 3.71. Next year’s workshop June 15-19 2015 will use the new code.

July 15, 2014: New updated post-processor with some of the error statistics fixed has been posted as well as an updated User Manual, a new preprocessor and a new model executable. The bug fixes and enhancements are shown in the W2 release notes. Most of these are minor fixes. The enhancements include more csv input file formats as input files. We are currently working on the sediment diagenesis model and several other major updates. We are hoping that a beta version will be available by September for download.

May 13, 2014: Some news on activity of model downloads: Between June 2004 and May 2014 there have been about 13,300 model downloads or about 1300/year from 159 countries. Of these downloads, 4280 were for Version 3.6, the prior model version. Since its beta release at the end of 2012, there have been 2523 Version 3.7 downloads through May 2014.

May 8, 2014: Update on CE-QUAL-W2 model testing and development. The 3.71 version model has been very stable with little updates/fixes over the last few months. We do have a few minor enhancements to add to the current version – these include adding more csv free format files as input files to the model. We are currently testing a beta version that we will be calling Version 4. This release will include simple sediment transport model (both organic and inorganic sediment deposition and resuspension), a sediment diagenesis model including bubble formation and sediment consolidation, new state variables CH4, H2S, more detailed metals in both water column and sediments, and a new steady-state river model formulation. We expect that the June 16-20 2014 Workshop at PSU will use the new Version 4.0Beta model to evaluate sediment processes in one or more example problems. To register for the workshop please go to http://www.pdx.edu/cee/QUAL-W2. Early registration ends on May 23. In addition, we are considering doing a 2-day advanced CE-QUAL-W2 workshop to consider in depth many of the new model features and how to make code changes in the model using Intel Visual Fortran. This would assume a basic level of running CE-QUAL-W2. We will post information about this new workshop soon, but expect this to be around January/February 2015. We are also working on many new features such as fish bioenergetics model, fish volitional movement model (updated version of Andy Goodwin’s model), particle transport model, updated selective withdrawal algorithm for complex outlet structures, automatic model running to meet selected targets, channel bottom heating, hyporehic flow and contaminant transport. We appreciate your feedback on the model and model tools from the download page.

April 18, 2014: We have been busy working on a host of new model features that we will be testing at our CE-QUAL-W2 workshop in June 2014. These new features include a full sediment diagenesis model, dynamic temperature and pH for the sediment diagenesis model, H2S, CH4 as new state variables, and metals complexation/release in the sediments, gas bubble production, and many other features. We do not expect to release this until late fall of 2014.

October 7, 2013: Added a w2 resource file for the source code that was inadvertently left out. Also updated the pdf user manual with bookmarks enabled for easier document navigation. No other changes were made in case you already downloaded the 10/3 release.

October 3, 2013: Many thanks to Bruce Willand for tracking down an error in SPECIFY for inflowing tributaries. This bug put an inflow 1 layer lower than it should have been. There were also significant updates/fixes to the PUMPS algorithm – especially when using the LAT option. Several other fixes were cosmetic in that they did not affect model results but cleaned up unallocated memory issues.

September 11, 2013: There were a couple minor bug fixes made (see release notes) and some updates/corrections to the User Manual in this updated release for today. Also, the new 32 bit executable for W2 should now run in XP. We are still looking at a few updates to the post-processor hopefully in the not-to-distant future.

August 14, 2013: We have migrated over to the latest Intel compiler XE 13.1.3 so we have new executables. We have noticed in some cases issues with the prior 32 bit executable – the new compiler seems to rectify these issues. There are a few other minor updates in the User Manual and minor fixes in this release.

June 25, 2013: There are several updates – not only bug fixes and User Manual edits, but speed improvements in the code. In my tests of the new code, limiting initialization of dimensioned variables in the code has improved computational time by between 2 (for a temperature only application) to 25% (for a water quality application with a large grid). There is also new w2tools Excel macro from Jeff Gregory, Corps of Engineers, Nashville District. Coming up soon will be an update to the W2Post post-processing tool – expect this in a couple weeks. These are mainly bug fixes rather than further enhancements.

April 5, 2013: A few minor bug fixes have been applied, more checks were added to the preprocessor, and the few minor items in the user manual has been updated.

November 5, 2012: I updated the download page to include an update to the preprocessor. We added more error trapping checks to prevent the preprocessor from bombing if there is a problem with an input file. So hopefully it will give you a much better idea of where there is a problem. Also, I added Jeff Gregory’s Excel macro utility that makes developing input files in Excel much easier. All other files are unchanged from the October 30, 2012 download.

October 30, 2012: We have finally released what we call Version 3.71 that includes the DSI Inc. post-processing tool. Also, we have made some code changes to improve the speed of computation. You should notice a speed up of 20% or more if you have a lot of water quality state variables. If you are running only temperature you may get up to 5% improvement in run times. Please let us know how this new post-processing tool works. Instructions are included in the model release notes.

September 12, 2012: Uploaded new W2 source files that included compiler files for Intel Visual Fortran Composer XE. Earlier compiler resource files were corrupted which caused heartburn for those trying to compile the code. All should work now by just opening up the Intel Fortran compiler files.

September 11, 2012: Added more free format input types: lpr and met input files to the model. We will post this new code and an Excel macro that makes it easy to output selections within Excel in csv format. Still waiting for post-processor release. The CE-QUAL-W2 workshop will be June 17-21, 2013 and will include a more thorough discussion of the new post-processor and how to easily develop input files with the new file formats.

August 20, 2012: Updating the code and preprocessor to accept free format inputs for input files. These will read the first character of the file – if the ‘$’ character is the first character in the file the model assumes it is a free format input file. A typical input file would be a csv comma delimited file. So far this now works with the following files: cin, ctr, cdtr, cpre, wsc, vpr, and the bathymetry file (already described in the manual). The manual will be updated once all these free-format input files are implemented in the w2 and prew2 codes. This will make it much easier to create all your input files. In addition the new post-processor should be ready for roll-out the end of this week or the first of the next week.

August 16, 2012: Still testing Paul Craig’s post-processor. It should make evaluating W2 model results incredibly easy and powerful. We should be ready to post the code soon for user evaluation. Added the Spokane River to the set of example problems in the download package.

August 7, 2012: We have been converting a lot of the code to full double precision constants and expressions to make the code’s numerical precision consistent. This will avoid the common problem when others try to compile the code without setting all default real numbers to double precision. Paul Craig has been fine tuning the post-processor that will be a very useful tool in using the model.

July 9 2012: We set the Version 3.7 download behind the registration page. The version 3.7 model is still missing one item before we are ready – this is the trapezoidal channel schematization. This has taken a lot longer than expected to debug. In a few days we will have Paul Craig’s post-processor available as part of the V3.7 download. This will be a free download and enable animation and easy post-processing of model results. Stay tuned.