multipliers file (Ks)

[Sanae]

Hello Shea

I find it difficult to understand how AGWA deals with hydraulic conductivity multipliers (for example). For my case study.  I have 4 soil types each with its own value of (Ks). 

but I am not able to determine a file that contains all values at once. I have to go to Kineros Simulation Information each time to enter the Ks value.

so in the end, I have 4 different results.

My questions are:

1- does Agwa always consider that the whole study area has the same value of (Ks) for Plans and Streams? 

2- how can I attach a single file that contains all the values of (Ks) at once?

Thank you 

Sanae

[Shea]

Hi Sanae,

1. Each soil type has it's own Ks value for every parameterization. You can see the Ks values for each soil type in the [discretization name]_temp_soil_lut in the delineation geodatabase. The Ks values in the temp_soil_lut for each soil type are weighted by the components and horizons (layers) of those components that compose the soil type. The Ks values for each model element are area-weighted based on how much of each soil type intersects the model element. So, unless the whole study area only has one soil type (which yours does not), then there will be more than one Ks value for the planes. The streams are defaulted to a Ks value of a sandy bottomed channel for the entire watershed, though this can and probably should be changed to better reflect the streams in your study area. Ks values for streams are set in the Element Parameterizer.
2. Are you asking about attaching them to a post in the Google Group? I think you want to look at the temp_soil_lut to see the Ks values for each soil type. That can be exported from the geodatabase to a different kind of table (CSV or DBF) from ArcMap.

I didn't discuss the multipliers here, but can discuss them if you like or have additional questions.

Shea

[Sanae]

Hello, Shea;

Thank you for your explanations, and sorry I couldn't answer earlier,

In fact, I would like to understand how can I attach a single file that contains all the values of multipliers (Ks) at once in AGWA in order to calibrate the model? 

Thank you

Sanae

[Shea]

Hi Sanae,

There are a couple of approaches you can use with multipliers because you can use a multiplier file in AGWA, but also use one directly with KINEROS2. The advantage of the AGWA multipliers is you can have a different KS multiplier for the plane elements than you do for the channel elements. The advantage of using a multiplier file with KINEROS2 is that you can use scripting to crank through hundreds or thousands of simulations that would be overly tedious to do in AGWA. Since you want to calibrate the model, I assume you'd prefer to use the KINEROS2 multiplier file instead of the AGWA multiplier option?

Shea

[Sanae]

Hi shea;

it's true that the advantage of AGWA multipliers is that I can have a different KS multiplier for plane elements than for channel elements. but in the end result, I got 4 finals maps instead of 1, because I have done 4 simulations. if I understand AGWA treats the different Ks values separately even if it belongs to the same catchment area.

My goal is to have a single final map that expresses the outputs of the model taking into account all the KS values at once, Is this possible with AGWA? 

thank you

Sanae

[Shea]

Hi Sanae,

Can you clarify a little more? Are you running 4 simulations because you're using 4 different multipliers? What do the 4 different simulations represent? If you want to apply different multipliers to different modeling elements, you'll have to do an additional step. Instead of using the AGWA or K2 multipliers, I suggest the following steps:

1. Create a new baseline parameterization that will be modified with multipliers
2. Add the parLUT parameterization attribute tables from the delineation/discretization geodatabase to the ArcMap document ([discretization name]_p_parLUT for the plane elements attribute table and [discretization name]_s_parLUT for the channel elements attribute table)
3. Open the planes or channels attribute table, perform a query to select the baseline parameterization from step 1 and the subset of plane elements to apply a unique multiplier, then use the field calculator to apply that multiplier to the Ks field
4. Repeat step 3 for each unique multiplier and subset of plane and or channel elements
5. Write the simulation input files for the parameterization that was modified in the preceding steps.

Let me know if this helps you move in the right direction, or if not I'll try again based on your clarification.

Shea

[Sanae]

Hello Shea;

I hope you and your loved ones are doing well in this time of health crisis.

Sorry, I haven't been able to work for the last few days, that's why I couldn't answer you earlier.

I've been trying to implement your advice, but how can I proceed with step three? 

I'm confused, each Ks value belongs to (element ID or Stream ID) of the map, each of these elements belongs to a specific soil class and therefore has a different KS value.

Do I have to look for the location of each element ID in the map and then change the Ks value?

Can you be clearer on how I can proceed in this step? 

P.S: I can't attach my files...Server error!! I'll transfer them by email.

thank you 

Sanae