# How to Create Cost Surface Raster for Least Cost Path Analysis?

I have a DEM raster and would like to carry out a cost path analysis.

Among other factors such as slope, proximity rivers etc. I would also like to take elevation into consideration. According to the model I am trying to build (using ArcGIS 10.1), the cost of building at high altitude locations would be much more costly compared to low altitude places.

I was wondering how I could create such a cost surface?

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Choose a range of values for costs (e.g. 1 = low costs, 10 = height costs).

Reclasify each input data to a cost raster.

e.g.:

reclassify elevation:

• altitude > 1000 m --> cost 10
• altitude 900 to 1000 m -> cost 9
• altitude < 100 m --> cost 1

reclassify proximity to rivers:

• distance < 10 m --> cost 1
• distance 10 to 200 m -> cost 2
• Distance > 2000 m --> cost 10

Combine all cost raster to a single cost raster. If a factor is more important than others you can use a different weight for each factor. Use Raster Calculator tool to calculate total costs. E.g. if elevation is more important than proximity to rivers you can use:

``````“cost_elevation” * 0.8 + “cost_rivers” * 0.2
``````