• flood
  • inundation
  • level
  • risk
  • water

1:50 Flood Map (2% chance of occurring in any year)

1:50 Flood Map (2% chance of occurring in any year)

(Note: Updated inundation maps for 1:2 to 1:1000 floods are available from Alberta Environment and Parks (2020). The new draft maps can be viewed here:

These inundation maps show whether a property is at risk for various sized river floods. The size of flood shown on this map has a 1/50 or a 2% chance of occurring in any year.

The three distinct types of inundation shown on the maps are:

o Inundation - Area flooded overland due to riverbank overtopping.

o Isolated - Low lying areas that will not be wet from riverbank overtopping, but may experience groundwater seepage or stormwater backup.

o Potential failure of flood protection barrier - Low lying areas that could be flooded if an existing permanent flood protection barrier were to fail.

The flood areas shown were mapped in 2015 jointly by Alberta Environment and Parks and the City of Calgary, using the best available hydrologic and hydraulic data and models. As such, the flooding shown reflects 2015 conditions, hydrology and topography. The effects of mitigation measures (changes to reservoirs/dams or barriers) built since 2015 are not included. There is uncertainty inherent in predicting the effects of flood events, and this uncertainty increases for floods with less than a 1% chance of occurrence in any year. Any use of this data must recognizing the uncertainty with regards to the exact location and extent of flooding.

More information on flood mapping for Calgary is available at

For Calgary's River Flood story, see:


NameSocrata field nameColumn name in sgr mountData typeDescription

Upstream Metadata