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Calgary river flows - historical data

The City of Calgary collects data of river flows on the Bow and Elbow River. Information on this page provides a historical look at river flows.

Historical flow rates for the Bow and Elbow Rivers

The term 1-in-100 refers to the probability of flooding, meaning there is a one percent chance in any given year that it may flood to the level we saw in 2013. Below are the annual return period (probability of occurring) flow rates. The City of Calgary has data back to 1870 for the Bow and Elbow Rivers. These graphs show the peak flow up to 2013.

​Return period ​Probability of occurence in any given year Elbow River above Glenmore Dam​ ​Elbow River below Glenmore Dam​ ​Bow River above Elbow River ​Bow River below Elbow River
​(years) ​(%) ​(m3/s) ​(m3/s) ​(m3/s) ​(m3/s)
​2 ​50 ​84.6 ​63.9 ​369 ​433
​5 ​20 ​194 ​143 ​659 ​802
​10 ​10 ​307 ​234 ​927 ​1160
​20 ​5 ​454 ​275 ​1230 ​1500
​50 ​2.0 ​708 ​494 ​1660 ​2150
​100 ​1.0 ​954 ​803 ​2020 ​2820
​500 ​0.2 ​1770 ​1690 ​2920 ​4610

The City of Calgary has data back to 1870 for the Bow and Elbow Rivers. These graphs show the peak flow up to 2013.

History of maximum flow in the Bow River

Maximum Flow Bow River 

History of flows on Elbow River (below Glenmore Dam)

History of flows on Elbow River