Relative vulnerability ratings of areas in Calgary's source watersheds. For more information, visit: http://www.calgary.ca/UEP/Water/Pages/Watersheds-and-rivers/Souce-Water-Protection.aspx

If a land use change or activity were to cause a release of contaminants, the vulnerable areas map indicates which areas are more or less vulnerable to facilitating the movement of contamination to surface waters downstream.

The "Final_rating" field is used to map the 5 categories. Please see the User Guide for detailed field descriptions:
https://data.calgary.ca/api/views/9k95-2tw9/files/ed1609d8-6be3-4776-ab79-823d0940c862?download=true&filename=SourceWaterVulnerability_UserGuide.docx