LPF package

[Brenda]

Hi all,

I have a question on the LPF package.

Why is the specific storage and speficific yield buttons unavailable when a steady state model is selected? With visual modfolw that I have been using until recently one can assign specific storage and speficific yield values to either a steady stae model or transient model. However, GMS would not allow me to do that with a steady state model. Is there another way of assigning these values when a steady state model is selcted?

Regards,

Brenda

[Alan Lemon]

If you look at the documentation for the LPF package here: http://water.usgs.gov/nrp/gwsoftware/modflow2000/MFDOC/lpf.htm

It has the following

Data Set 13

[ss(NCOL,NROW)]- U2DREL

Include item 13 only if at least one stress period is transient. If there are any SS parameters, read only a print code.

Ss

Data Set 14

[sy(NCOL,NROW)]- U2DREL

Include item 14 only if at least one stress period is transient and LAYTYP is not 0. If there are any SY parameters, read only a print code.

Sy

So MODFLOW only reads these data sets if at least one stress period is transient. GMS does not save the SS/SY values separate from the MODFLOW inputs.

[elkan]

Dear Aquaveo Forum,

I am doing a modflow simulation with LPF package. I am still at calibration stage with some coverages( recharge, source&sinks & observation well). I use recharge zones for automated parameter estimation.

Is there any way to use "hydraulic conductivity" for automated estimation, while I use material set (generated by T-progs) which can only be altered in "material properties" in "MODFLOW | LPF package" option.

Cheers,

Elkan

[Alan Lemon]

Yes you can use materials with the LPF package and have the HK be a parameter. Go into the material properties dialog and put in a "key" value (negative number) for the HK for the material that you want PEST to estimate. Now go to the MODFLOW | Parameters dialog and select the "Initialize From Model" button. This should find your new HK parameter.

[cansudemir]

Dear @Alan Lemon,

Regarding your above reply; In my case similar to above, when I assign negative values for HK zones, the run results completely wrong. With the negative values I do can create key parameters by using "initialize from model".  But the model doesn't run properly. On the other hand, with positive HK values I got a successfully finished run. However in this case, I couldn't initialize the key parameters from the model and don't know how to create parameters by hand. What should I do? Should I just add new parameters? If so, how does the program understands that these parameters indicate my assigned HKs?

Best,

Cansu

[Alan Lemon]

It is difficult to answer this question without seeing your model. I don't know of any reported bugs with this feature so you may have missed a step. If you need further help feel free to contact support.