S-3.1.01, r. 1 - Dam Safety Regulation

Section 21 Disposition versions

2014-11-13

21. Subject to sections 21.1, 22 and 24, every dam must be able to withstand any of the following safety check floods, taking into account the highest dam failure consequence category in flood conditions:

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Highest dam failure consequence category                      Safety Check Flood           
       in flood conditions            
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  Very low or low                                                 Centennial*      
                                                                (1: 100 years)
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  Moderate or high                                                Millennial*      
                                                               (1: 1,000 years)     
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  Very high                                                    Decamillennial*     
                                                              (1: 10,000 years)
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  Severe                                                     Probable maximum flood
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* Safety check floods expressed according to their recurrence interval.

O.C. 300-2002, s. 21; O.C. 901-2014, s. 2.

2012-09-01

21. Subject to sections 23 and 24, the characteristics of every dam must ensure that it can withstand as a minimum the safety check flood described in the table below that corresponds to the failure consequence category of the dam under sections 17 and 18. However, if the dam failure consequences were assessed on the basis of a dam failure analysis, the category to be considered for the purposes of the table is the highest consequence category resulting from the examination of dam failure scenarios in flood conditions.

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    Consequence Category         Safety Check Flood
                                (Recurrence Interval)     
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       Very Low or Low              1:100 years        
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      Moderate or High             1:1,000 years       
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         Very High           1:10,000 years or ½ PMF  
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           Severe            Probable maximum flood (PMF)  
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O.C. 300-2002, s. 21.