Bessette E.Coli

  E.coli
primary contact maximum 77(*)
mid November 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 g-Mean
Harris 7 20 25 10 50 50 130 57 82 23 17   30
Duteau 12 34 21 19 10 7 12 46 54 19 24   20
Vance     8 4 -- -- 2 2 5 1 15   4
Mid Bessette 13 11 51 18 42 60 67 131 60 93 34   41
Lower Bessette 11 10 43 30 76 91 77 35 8 66 11   30
geometric Mean 10.5 16.5 24.7 13.3 35.5 37.2 27.7 29.9 25.4 19.3 19 #VALUE!  
mid September                          
Harris 190 26 73                   71
Duteau 78 170 180                   134
Vance     11                   11
Mid Bessette 210 120 120                   145
Lower Bessette 89 53 64                   67
geometric Mean 129.0 72.8 64.4                    
mid August                          
Harris 2100 270 230 570 580 900 1000 489 297 271 293   496
Duteau 380 190 110 240 1000 77 210 101 11200 305 82   281
Vance     29 36 240 27 96 15 59 54 56   49
Mid Bessette 290 270 140 370 710 270 560 224 639 511 107   318
Lower Bessette 250 290 150 140 240 230 340 109 115 307 74   184
geometric Mean 490.4 251.8 109.0 191.1 473.2 163.3 328.7 112.6 428.4 233.9 101 #VALUE!  
mid July                          
Harris 80 190 1900                   307
Duteau 330 310 600                   394
Vance     260                   260
Mid Bessette 2 150 2000                   84
Lower Bessette 51 100 500                   137
geometric Mean 40.5 172.4 784.1                    
mid May (freshet)                          
Harris 140 20 22 23 48 150 33 23 102 119 24 687 58
Duteau 180 29 55 82 44 80 200 52 824 33 215 210 100
Vance     1 22 4 2 1 1 <1 423 2 5 4
Mid Bessette 88 31 41 71 150 33 130 40 127 43 72 248 72
Lower Bessette 56 36 43 89 39 37 110 53 228 40 105 291 72
geometric Mean 105.6 28.4 18.4 48.3 33.9 31.1 39.4 19.0 222.1 77.8 38 139  
mid April                          
Harris 12 24 52                   25
Duteau 30 11 43                   24
Vance     --                   --
Mid Bessette 26 18 45                   28
Lower Bessette 17 35 22                   24
geometric Mean 20.0 20.2 38.6                    

 

 

(*) Primary Contact Maximum :-

B.C. provincial standard for recreation with most of the body in the water and risk of ingestion (e.g. swimming)
It now refers to the Canadian standard, but used to be lower. It's now 200/100mL.

Both references speak of the geometric mean of several samples, as opposed to single-sample maximum. The standards quoted here are for the geometric mean, a lower maximum than allowed by a single sample result.