Curve Number Determination Process by Land Use and Soil Data Using ArcGIS Pro

[@lalkhan162]

A great video. Please add references or links to Soil Group and land use data that you have used in this example.

[@amineouazad886]

Nice video. I could suggest a workflow in GDAL, which could significantly speed up the workflow.

[@senkam9190]

Thanx a lot for the good explanations . 1. What Projection are you using in your data. Want to replicate the results. 2. In case we want the CN for each sub-watershed, how can we get/extract the average of each sub-watershed ? Do we have to use the shapefile for the sub-watersheds (LMW_HU10 in your example). Instead of the shapefile for the entire watershed boundary (LMW_HU8) 3. Does the raster data resolution has to be the same for each raster (Soil, LULC, slope [DEM]) Since the soils & land use are 30 m resolution raster, your DEM must be the same resolution, right ?

[@HydroMohsen]

Glad you liked it! I think I used UTM Zone 15 for projection. If you want CN for each subbasin, do a zonal statistic in Arc Pro. I might make a video on that! And the same resolution is not required but it helps with the accuracy.

[@senkam9190]

There must be a video before this or right after the Soil [download & process] video . In the soil video, the soil Hydrogps has soil types [null, A, A/D. B, B/D, C. C?D, D, D/C & all other values]. At the end of the soil video you mentioned to keep all files [wshed boundary, LCLU & Soil hydrogpdc]. This CN video however, started i) without any reference to any further processing of the soil file. ii) The soil file added on this video [curve number calc] shows soil types A, B, C, D, & all other values only. Which is different from the one we had at the end of the soil video. I replicated everything upto that point. Have you processed the soil Hydrogpdc [ even the LULC] further, to make it only 4 soil types? If so, what did you perform on it to get it to the types shown on this video?

[@HydroMohsen]

Good catch! Here are the steps: you can open the attributes table of the soil shape file and perform a search by attributes. Search for A/D for example, and edit the to either A or D. Considering D is more conservative. Do the same for other mixed soil hydrogroup types. Once you are done, you will have a soil shape file similar to what I have at the start of the CN video.

[@connormaimone7900]

Where did you find the hydrologic soil data? I need data for Wisconsin but I've checked basically everywhere I can think of and I still haven't found it.

[@HydroMohsen]

Check this out: nrcs.app.box.com/v/soils/folder/17971946225

[@connormaimone7900]

@@HydroMohsen Thank you very much, this was extremely helpful.

[@ahmadsameershahim6164]

How to find this CN table?

[@MyIndia2100]

Dear sir, can you tell me where you get the table for curve number. What should be the value for permanent ice/snow

[@tauraichigovanyika8430]

Thanks for this :) is there a paper written on this too? So, i can "reference" it and give credit for part of my methodology?

[@HydroMohsen]

There is not! Buy me a cup of coffee instead if you see me at a conference ;)

[@muhammadismael9746]

Where can I find curve number table

[@hikikomorihachiman7491]

Thank you a lot

[@Emma-np3hp]

Would you have to do this separately for each subbasin?

[@HydroMohsen]

You can do it once for the entire watershed and the generate a summary for each subbasin.

[@cedricajeneza1988]

Where did you find the hydrologic soil data? I need data for AFRICA (Burundi)

[@HydroMohsen]

check this out: daac.ornl.gov/SOILS/guides/Global_Hydrologic_Soil_Group.html

[@Revivification-b9h]

sir can you please provide the same file that you worked on in this video.....I want to to the exact same as shown in this video

[@user-gf9955]

Do you have chinese data?I can't find Soilgroups and landuse data with china.

[@斑马条纹男孩]

你好，请问你找打到了嘛