Development Suitability Analysis

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For one of the scenarios in this week's lab, I was playing the role of a GIS Analyst for a property developer. My task was to create a map showing suitable land for development based on the following criteria: 

  • Land Cover
  • Soils
  • Slopes
  • Streams
  • Roads 

My general process for this analysis was to first convert all of these layers into rasters if they weren't already. For the rivers and roads layers, I used the Euclidean Distance tool to calculate the shortest distance from each cell to the nearest river or road. I then reclassified each of these layers based on a suitability scale of 1 - 5. Lastly, I combined the results of each of these five criteria using the Weighted Overlay tool. Below are my results. 


The first map is an equally weighted average where each of the five criteria have an influence of 20% (or 1/5th). The second map shows an alternatively weighted output where each of the five criteria were weighed as follows: 
  • Land cover (20%) 
  • Soils (20%)
  • Slope (40%)
  • Distance to Streams (10%)
  • Distance to Roads (10%)
Least suitable areas for development are shown in red and most suitable areas are shown in dark green. 


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