How to Update a DEM with Survey Data?

In most of the times the Analyst identify the data inadequacy for caring out the task. In that time analyst need to update existing database with newly collected data. 

In irrigation and water supply development projects needs DEM, in such cases, Update the DEM with new survey data is Important.

How to face this Challenge?

We  have 

1. Existing DEM (Most properly in *.img format)

2. Survey Data (XYZ data, in Excel sheet)

Workflow:

1. We need to be open ArcMap, and add these two data.

2. Convert Point data into Shape file 

(Use Display XY data)

3. Define the Interest area 

(Create new polygon layer and draw a polygon where the Survey Data available )

4. Develop TIN layer 

( 3D analyst toolbox  Data Management > TIN > Create TIN )

5. Convert TIN to Raster

 ( Conversion > From TIN > TIN to Raster )

6. Clip Raster using Area of Interest Polygon 

( Data Management > Raster > Raster Processing > Clip)

Note: Make sure the Check box of "Use input features for Clipping Geometry 

7. Update Existing Raster DEM using Newly Created Raster 

( Data Management > Raster > Raster Dataset > Mosaic to new Raster )

Note: 

Input Raster : Newly Created Raster, Existing DEM ( Keep order)

Output Location : Specify as your request

Raster Dataset Name with Extension : Specify as your wish but do not forget to add extension (Ex. Updatedem.img) (*.img is recommend for open dataset in different applications)

Pixel Type : If your Survey Elevations have Negative values then use signed, otherwise maintain your existing DEM pixel type.

Mosaic Operator : First (If your order is other-way round, keep last)

8. Click OK, your DEM is updated!!