Where can I download elevation data to use as a Surface?

Where can I download elevation data to use as a Surface?

Anonymous
Not applicable
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Message 1 of 8

Where can I download elevation data to use as a Surface?

Anonymous
Not applicable

Is there somewhere that I can download elevation data of a region to then use as a Surface? I have downloaded elevation data from USGS but it is not in a file format that is easily used as a Surface in Autodesk Civil 3D 2019. 

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7 Replies
Replies (7)
Message 2 of 8

samir_rezk
Advisor
Advisor

Hi,

i often use more local GIS data like the town or state, and subsequently use the create surface from GIS command under the home tab/create ground data panel/ surface drop down! However chances are the data you have from from USGS is a .las or .laz file, essentially these are Lidar scan point clouds. If you have civil 3d 2018 or later you first are required to process the point cloud in ReCap and then proceed to creating a surface from point cloud back in civil 3d.

hope this helps,


Samir Rezk
Technical Support Specialist

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Message 3 of 8

Jeew-m
Mentor
Mentor

Hi,

Check this video and see if it helps you.

 

 

Thanks



Jeewana Meegahage
Design Engineer
Autodesk Civil 3D Tutorials
Facebook | YouTube | LinkedIn







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Message 4 of 8

Anonymous
Not applicable

Hello @Anonymous ,

Please use the following links to dowload freeware GIS data:

http://srtm.csi.cgiar.org/

 

Regards,

Jatin

 

 

 

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Message 5 of 8

Anonymous
Not applicable

Thanks for that link. I found the location I need and downloaded the file (.tif). I then imported the data into ArcMap and cropped the file and exported a smaller .tif file. I then went to Civil 3D and tried the Surfaces --> Create Surface from DEM --> selected my file. However, it says it can't read the file? 

I only need a tiny section of elevation data right around Lenhartsville, Pennsylvania. (40.576366, -75.887110)

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Message 6 of 8

Hidden_Brain
Advisor
Advisor

Since you have access to ArcMap, I would use:

https://viewer.nationalmap.gov/basic/

 

download the data in the IMG format, pass thru ArcMap to convert to esri grid (.adf) that can be directly used in Civil 3D to create a tin.

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Message 7 of 8

jefflambert9091
Advisor
Advisor

Looks like you are close. It may be how you cropped. I use the original file, zoom to the area limits I want on my screen and then "Project to Raster". In my environments - Processing Extent - I select same as display. Then Conversion Tools Raster to ASCII to make a txt file. (Sorry for the edit- forgot the last part!)

Jeff
Civil 3D 2024
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Message 8 of 8

Anonymous
Not applicable

There is heaps of sources, best to use the most local one to get accurate data just google LiDAR and your city name.

On another note, on a global scale, this website has a cool interface

http://dwtkns.com/srtm/

If you are after tips on how to integrate the LiDAR information into your topo data, check out this course:

https://www.udemy.com/mastering-autocad-civil-3d-working-with-surfaces/?couponCode=CADFORUM

 

 

 

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