I have a dewatering project next to an area of saline groundwater. The dewatering wells would probably pump saline water, with increase values along time.

I would like to model the salinity process on the dewatering site, while estimating the chloride concentration at each pumping well (about 10 well along the site borders)

Is there an option to have concentration vs. time at each pumping well?

Thanks,

Yoni

]]>I have recently started using the UZF package to simulated groudwater flow in a regional model. I firstly developed a steady state model using spatially distributed recharge from a surface model. I was using the «recharge» and the «EVT» package. With this configuration i was able to obtain a water budget with % error < 0.001%. When i replaced the recharge and EVT packages by the UZF, the water budget output file shows a line with a component called «HORT+DUNN» which i suspect to be the surface runoff flow. This component is not well describe in the USGS MODFLOW documentation. The problem is that this volume of water is only present in the «IN» part. In then creates a poor water balance ~1% to 5% error. If i remove it from the balance, the % error is good (> 0.01%).

Any idea of how to deal with this water budget component?

Regards

]]>

Could you please tell me if a SEWAT model can be calibrated using PEST in GMS?

This model was calibrated in the mode of MODFLOW using PEST. However, it does not take the effect of the salinity wedge intruded inland along the coastline (although the GMS set up of this model includes all MODFLOW, MT3DMS and SEWAT and salinity wedge and associated coastline boundary conditions). Using the calibrated hydraulic conductivities, vertical anisotropies and recharge rates, The model was run in SEWAT form but water levels are much higher than the calibration targets now because the salinity wedge is holding the water flowing towards the ocean. Therefore, I think it is best if the calibration can be done using SEWAT itself rather than using MODFLOW. Please let me know if you have a different opinion. I appreciate it very much.

Thank you,

Lalith

]]>I have a SEAWAT simulation with the constituents in it. It was developed using GMS. I also saved the model in regular text based form of USGS. I am using this USGS format to conduct simulations. It has 44 stress periods. I want to run the simulation for a shorter duration (starting date does not change but only the ending date changes). I changed the number of time steps in .dis file (NPER) but simulation continues all the way to the end (44 stress periods). Then, I also changed the relevant time step information in .btn file (NPER – record 3, NPRS – record 16, TIMPRS(NPRS) - record 17, record A21s) and then simulation does not progress. Can you please help me to run the simulation to run for a shorter duration in USGS form?

Thank you,

Lalith

]]>I am building a transient MODFLOW model with GMS 7.0 using the conceptual model approach.

There is a huge problem with the number of stress periods I want to run :

- Until I've less than 1001 stress periods, MODFLOW runs, everything is ok

- If I have more than 1000 stress periods, MODFLOW aborts immediatly (I mean it is not a problem of convergence)

Hereunder the error message :

"Excutable started

.....

This file is not a GMS MF2K superfile. Assuming NAM file

......

ALLOCATION OF ARRAYS X, Z, IX AND XHS FAILED

RETURNED ERROR MESSAGE NUMBER : 41

MODFLOW 2000 finished"

I have made many many tests with my files and I have also tested it with entering the data manually directly in the Stress Priod box in Global Options.

Moreover, I don't understand because the option of output control "Enable saving of computed flows for all source sink object" is already unchecked...

Thanks in advance for any help !

]]>How easy is it to integrate or interface GMS generated MODFLOW models with MIKE FLOOD?

Any thoughts on how to do this directly or indirectly will be greatly appreciated.

Cheers

Hisham

I have attached below images of the conceptual for flat and sloping scenario for reference. Any assistance would be greatly appreciated.

Many thanks,

Matthew

]]>I am trying to calibrate a MODFLOW model using PEST. My model has multiple layers (12). However, I do not know how to parameterize the model. Aquaveo tutorials explain it as specifying hydraulic conductivity and recharge values are negative values in different areas. However, I am not able to do this because my model is developed in such a way that these Hydro-geological properties are specified as a properties of materials and these materials are assigned to different areas in each layer. Would you please help me to parameterize my model?

Thank you,

Lalith

]]>I am running a two layer elevated aquifer in modflow with the hydraulic conductivity of the lower level reduced to a negligible value to explore the impact of elevation on the water table. The problem I am having is that water is leaking into the lower aquifer. Does anyone know of an alternative way to replicate this scenario in Modflow? Thanks

]]>I have created MODFLOW model for a region near the coastline and It ran successfully in both steady and transient state. Currently there is no sink or source terms to make the model simple. Once the model achieve a stable solution, they will be added later. Then, I tried to run it in with SEAWAT and model shows the error that Memory is not enough.

I tried both Parallel, 64Bit options as well as both of them in combination but did not get any luck. The way that I ran the SEAWAT model is as follows. I assume that I did it correct but** please let me know if you have any alternative ways**.

1. Run MODFLOW in steady state.

2. Change the model and output to transient state.

3. Assign steady state heads in step 1 above as the initial heads for the run.

4. Map MODFLOW to the grid.

5. Map MT3DMS to the grid.

6. Run SEAWAT.

My model grid has 512 x 646 x 12 cells (12 layers). Number of total and active cells are 3,969,024 and 1,416,464 respectively .

Since I did not have any success in running the model in GMS, I decided to run the SEAWAT model in text based USGS format. I exported the MODFLOW model from GMS to the regular text based USGS format. However, I do not see such a format change for either MT3DMS and SEAWAT option in GMS.

1. I assume that either MT3DMS or SEAWAT does not require such a conversion. **Please correct me if I am incorrect. **

2. Also, I think that the SEAWAT name file in the SEAWAT folder that GMS produces (.swn file) may not be the correct one ** to run SEAWAT in USGS format **because the type, format, number of files and the content in the files are different. Please see the files and sizes of GMS and USGS formats of MODFLOW in the screen shots below.

I am planning to use the USGS version of SEAWAT executable and/source code to run the model since Aquaveo executable might have been customized to its data file types and may not match the requirements. **Please let me know if you have any suggestion on this.**

I very much appreciate all your thoughts, suggestions and help to resolve this issue.

Best regards,

Lalith

]]>

I have trouble modeling a square site with different BC.

at one side I have river (I put constant head as BC) and no problem in that for modeling.

now,

1) at one side I have rock (no flow coming in or out from site at this side) and

2) at other side of square area I have no BC (I mean the water can flow out of area etc)

what is the difference in modeling number 1 and 2? how to difine them in my model? my model currently have active cells in coverage so I think it means all sides I have rock, right?

Thank you,

Zara

]]>I have a MODFLOW project that I am creating with GMS for a class at UCLA, and I need to convert it to be read into the MODELMUSE software so I can submit my assignment and the TA can grade it. Does anyone know how to convert a GMS MODFLOW into MODELMUSE MODFLOW?

Steve Turnbull

cell 808-295-4998

]]>I am currently trying to build a model in MODFLOW-USG similiar to a model in MODFLOW-NWT. My NWT model is fast and robust.

I have tried to build a similar model of the same area in USG in different ways, ending with the same problem. The model will not converge if any cells is dry. I discovered this by adjusting the recharge parameter. My USG model converged when the recharge was extremely high and no cells were dry.

I tried to "convert model to MODFLOW-USG simulation" in GMS to check if the model would converge when there was no difference in grid structure. I get the same result. I need to increase the recharge to have no dry cells and a model that does not crashes.

Can anyone tell me if the SMS solver in MODFLOW-USG can be set up in the same way as the NWT solver to handle dry cells, and how?

Martin

]]>

I have a problem regarding flooding and wetting which makes it difficult to calibrate the model. It is representing a coastal area with thin clay layers and sandy till which we assumed to be 1 m each. The two bottom layers represent rock with the upper one being fractured and thus have a higher hydraulic conductivity. The surfaces are imported from ArcMap and ranges between 30 and 0 m. constant head and no-flow was assumed.The main problem I found is that the groundwater table is almost completely flat in contrast to the terrain.

Any ideas of packages, solvers or any tips in general, of how we can tackle the issue. We are thankful for any answers that could help us!

]]>

Cell elevation (based on surface elevation raster) is 14.18 m, bottom is 12.0. The mapped drain elevation is 11.3. WTH? I've deleted and recreated and mapped MODFLOW 3 times, no change.

]]>

Can anyone please tell me that **how velocity is calculated from flow data in GMS**(not through GUI).

Though I had already referred to the following the link:

https://www.aquaveo.com/blog/2012/05/15/velocity-vectors

,the velocity calculated by me is not matching the velocity obtained through GMS.

I had applied the following for the calculation of velocity:

** V = Q/(saturated_area*porosity);**

where,

Q is the **flow through a cell face**, obtained from ccf file,

Saturated area = (**head-bottom_elevation**)*cell_width {for unconfined aquifer}

and head is obtained through .hed file.

Thanks in advance. Have a great day!

]]>Thanks,

Imri Oz

]]>]]>

I have encountered an error in mapping solids to Modflow layer.

I have got an error which is mentioned in the attached figure.

I will be thankful to you if you can clear my doubt.

]]>

I have a problem when i run Simulation and it stops in middle of running

__FAILURE TO MEET SOLVER CONVERGENCE CRITERIA
BUDGET PERCENT DISCREPANCY IS -141.2903
STOPPING SIMULATION__

__can anyone help me with this issue?__

__Thanks__

I have a issue with defining inflow rate to related cells. I have the total volume of inflow for each month (i want make a time series general head), but i dont know how i should define the head of the 2 points of inflow line & amount of conductivity correctly. (for example the volume of inflow is 110 MCM & the length of inflow line is 97 KM and Average elevation of area is 1900 m)

If anyone can help me it would be great.

]]>